Eco-Architecture Harmonisation between Architecture and Nature
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FIRST INTERNATIONAL CONFERENCE ON HARMONISATION BETWEEN ARCHITECTURE AND NATURE
ECO-ARCHITECTURE
CONFERENCE CHAIRMEN G. Broadbent University of Portsmouth, UK C. A. Brebbia Wessex Institute of Technology, UK
INTERNATIONAL SCIENTIFICADVISORYCOMMITTEE S. Badanes M. A. Baez N. Baker R. Borges D. Bosia P. Brimblecombe E. Constanzo E. Cullinan J. M. de Bottom
M. L. Garrison M. Hejazi B. A. Kazimee D. Lewis G. Manioglu A. Marcomini R. Pulsell S. Roaf G. Rosenhouse
N. Sala D. Sheppard E. Stach W. Timmermans J. Tomlow T. J. Truesdale A. van Timmeren K. Yeang R. Zmeureanu
Organised by Wessex Institute of Technology, UK In Collaboration with International Journal of Ecodynamics Sponsored by WIT Transactions on Ecology and the Environment
Transactions Editor Carlos Brebbia Wessex Institute of Technology Ashurst Lodge, Ashurst Southampton SO40 7AA, UK Email:
[email protected]
WIT Transactions on The Built Environment Editorial Board
E Alarcon Universidad Politecnica de Madrid Spain
C Alessandri Universita di Ferrara Italy
S A Anagnostopoulos University of Patras Greece
E Angelino A.R.P.A. Lombardia Italy
H Antes Technische Universitat Braunschweig Germany
D Aubry Ecole Centrale de Paris France
D E Beskos University of Patras Greece
J J Bommer Imperial College London UK
F Butera Politecnico di Milano Italy
P G Carydis National Technical University of Athens Greece
J Chilton University of Nottingham UK
S Clement Tranport System Centre Australia
M C Constantinou State University of New York at Buffalo USA
G Degrande Katholieke Universiteit Leuven Belgium
A De Naeyer Universiteit Ghent Belgium
W P De Wilde Vrije Universiteit Brussel Belgium
J Dominguez University of Seville Spain
F P Escrig University of Seville Spain
M N Fardis University of Patras Greece
C J Gantes National Technical University of Athens Greece
L Gaul Universitat Stuttgart Germany
Y Hayashi Nagoya University Japan
M Iguchi Science University of Tokyo Japan
L Int Panis VITO Expertisecentrum IMS Belgium
W Jager Technical University of Dresden Germany
C M Jefferson University of the West of England UK
D L Karabalis University of Patras Greece
E Kausel Massachusetts Institute of Technology USA
K Kawashima Tokyo Institute of Technology Japan
A N Kounadis National Technical University of Athens Greece
W B Kratzig Ruhr Universitat Bochum Germany
A A Liolios Democritus University of Thrace Greece
J W S Longhurst University of the West of England, UK
J E Luco University of California at San Diego USA
L Lundqvist Unit for Transport and Location Analysis Sweden
M Majowiecki University of Bologna Italy
G D Manolis Aristotle University of Thessaloniki Greece
G Mattrisch DaimlerChrysler AG Germany
F M Mazzolani University of Naples "Federico II" Italy
K Miura Kajima Corporation Japan
G Oliveto Universitá di Catania Italy
E Oñate Universitat Politecnica de Catalunya Spain
A S Papageorgiou Rensselaer Polytechnic Institute USA
G G Penelis Aristotle University of Thessaloniki Greece
A M Reinhorn State University of New York at Buffalo USA
F Robuste Universitat Politecnica de Catalunya Spain
C W Roeder University of Washington USA
J M Roesset Texas A & M University USA
M Saiidi University of Nevada-Reno USA
F J Sanchez-Sesma Instituto Mexicano del Petroleo Mexico
S A Savidis Technische Universitat Berlin Germany
J J Sendra University of Seville Spain
Q Shen Massachusetts Institute of Technology USA
A C Singhal Arizona State University USA
P D Spanos Rice University USA
C C Spyrakos National Technical University of Athens Greece
H Takemiya Okayama University Japan
I Takewaki Kyoto University Japan
E Taniguchi Kyoto University Japan
J L Tassoulas University of Texas at Austin USA
M A P Taylor University of South Australia Australia
R Tremblay Ecole Polytechnique Canada
R van der Heijden Radboud University Netherlands
R van Duin Delft University of Technology Netherlands
A Yeh The University of Hong Kong China
M Zador Technical University of Budapest Hungary
R Zarnic University of Ljubljana Slovenia
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Eco-Architecture Harmonisation between Architecture and Nature Editors G. Broadbent University of Portsmouth, UK C. A. Brebbia Wessex Institute of Technology, UK
G. Broadbent University of Portsmouth, UK C. A. Brebbia Wessex Institute of Technology, UK
Published by WIT Press Ashurst Lodge, Ashurst, Southampton, SO40 7AA, UK Tel: 44 (0) 238 029 3223; Fax: 44 (0) 238 029 2853 E-Mail:
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[email protected] http://www.witpress.com British Library Cataloguing-in-Publication Data A Catalogue record for this book is available from the British Library ISBN: 1-84564-171-X ISSN: 1746-4498 (print) ISSN: 1743-3509 (online) The texts of the papers in this volume were set individually by the authors or under their supervision. Only minor corrections to the text may have been carried out by the publisher. No responsibility is assumed by the Publisher, the Editors and Authors for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions or ideas contained in the material herein. © WIT Press 2006 Printed in Great Britain by Athenaeum Press Ltd., Gateshead. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the Publisher.
Preface This book contains the edited papers of the First International Conference on Harmonisation between Architecture and Nature (ECO-ARCHITECTURE 2006), which took place at the Wessex Institute of Technology Campus in the New Forest, UK. Unlike the mechanistic buildings it replaces, Eco-Architecture is in harmony with nature, including its immediate environs. Decisions have to be taken on ecological grounds concerning locations, siting and orientation, as well as the wellinformed choice of materials. Eco-Architecture makes every effort to minimise the use of energy at each stage of the building’s life cycle, including that embodied in the extraction and transportation of materials, their fabrication, their assembly into the building and ultimately the ease and value of their recycling when the building’s life is over. The design may also take into consideration the use of energy in building maintenance and changes in its use, not to mention its lighting, heating and cooling, particularly where the energy consumed involves the emission of greenhouse gases. Substantial savings can be achieved by passive energy systems, especially natural ventilation, summer shading and winter solar heat gain. Solar energy may be used in panel pipes for heating water and photovoltaic cells. The development of Eco-Architecture is driven by the depletion of natural resources, especially fossil fuels and the need to preserve the balance of nature. The extensive use of steel and glass and the built-in problems of discomfort from solar over-heating and winter heat loss, has led to the widespread use of mechanical systems. Eco-Architecture is providing instead imaginative and expressive solutions driven by a generation of highly creative designs. It has important cultural as well as architectural impacts. Eco-Architecture is by definition inter-disciplinary; it requires the collaboration of engineers, planners, physicists, sociologists, economists, and other specialists, in addition to architects. The papers contained in this book were written by different specialists and attempt to focus on the interdisciplinary character of eco-architecture. The editors are grateful to all the authors for the quality of their papers and to the members of the International Scientific Advisory Committee as well as other colleagues who helped to review the papers. The Editors, The New Forest 2006
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Contents Section 1: Ecological and cultural sensitivity Cultural responses to primitive needs N. Baker ................................................................................................................3 Ecological propriety and architecture V. A. Metallinou ..................................................................................................15 Architecture and nature at the end of the 20th century: towards a dialogical approach for sustainable design in architecture F. J. Soria López .................................................................................................23 The keyword is quality not ecology A. van Hal ...........................................................................................................35 In-between architecture and landscape, from theory to practice B. Ott ...................................................................................................................45 Ecological, modular and affordable housing J. Quale ...............................................................................................................53 Flexi-Living: adaptable property, adaptable housing, transforming lives I. MacBurnie .......................................................................................................63 The study of restoring an eco-habitat of the traditional Paiwan tribe in Taiwan C.-J. Chen ...........................................................................................................73 Urban planning and the quality of life in Putrajaya, Malaysia D. Bt Omar ..........................................................................................................83
Section 2: Historical and philosophical aspects Evaluating the sophistication of vernacular architecture to adjust to the climate E. Tsianaka..........................................................................................................93 Examining line as a heuristic device in the design ethos of Alvar Aalto P. Harwood .......................................................................................................103 Historical influences of wind and water in selecting settlement sites P. Kilby..............................................................................................................115 Unity, simplicity and balance: sustainable management of cultural historic environments of mountain summer farming G. Swensen ........................................................................................................123 A tale of two city halls: icons for sustainability in London and Seattle D. Armpriest & B. Haglund ..............................................................................133 Poetic water images in architecture U. Kirschner......................................................................................................143 Section 3: Design with nature The 2005 Solar D house M. Garrison.......................................................................................................155 Fractal geometry and architecture: some interesting connections N. Sala ...............................................................................................................163 Symbols, metaphors, analogues: seeding, modelling and achieving sustainable design R. J. Koester ......................................................................................................175 A methodology for sustainable design analysis of large scale buildings R. Richarde & R. Ibrahim .................................................................................185 Developing designs in balance with nature A. J. Anselm.......................................................................................................195 Outdoor residential landscape design in an arid natural conservation area: Bahía de Los Ángeles, México R. Rojas-Caldelas, G. Bojórquez-Morales, A. Luna-León, E. Corona-Zambrano & J. Ochoa-Corrales .....................................................205
The house by the lake C. A. Brebbia & J. Gorst...................................................................................215 Indicators for the ecological planning of buildings C. Seyler, C. Stoy, I. Lützelschwab & S. Kytzia ................................................227 Sustainable building design in Australia C. McCabe ........................................................................................................237 Design and construction: changing the role P. Rossi..............................................................................................................247 Section 4: Assessment and selection of materials Natural materiality – the people’s choice F. Stevenson ......................................................................................................257 Environmental impact of materials used in technical equipments: an overview on different methods L. Marletta, G. Evola & F. Sicurella ................................................................267 Designing for longevity V. Straka............................................................................................................277 Natural building systems: experiments in urban ecology K. Connors ........................................................................................................287 Promoting sustainability of earth constructed private and public buildings in South Africa G. Bosman .........................................................................................................297 Section 5: Natural technologies Heteronomy and (un)sustainability of essential technical infrastructures A. van Timmeren ...............................................................................................309 Eco-design of technological systems in buildings L. Marletta, G. Evola & F. Sicurella ................................................................319 Section 6: Design by passive systems Sound barriers to enable open windows and integration in landscape G. Rosenhouse...................................................................................................331
Practicing what we preach M. Lawton .........................................................................................................341 Guidelines for sizing roof windows S. Robertson & M. Thompson ...........................................................................351 Section 7: Building operation and maintenance Building defects: survey and impact over sustainability E. Costanzo .......................................................................................................361 Cob seismic rehabilitation G. Scudo & A. Drei ...........................................................................................369 Section 8: Water conservation Rainwater harvesting in Brazil: investigating the viability of rainwater harvesting for a household in Brasília D. Sant’Ana .......................................................................................................381 Reliability of rainwater harvesting J. W. Male & M. S. Kennedy .............................................................................391 User experiences with decentralised water systems in an ecological residential area A. A. E. Luising .................................................................................................401 Author index ....................................................................................................409
Section 1 Ecological and cultural sensitivity
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Eco-Architecture: Harmonisation between Architecture and Nature
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Cultural responses to primitive needs N. Baker The Martin Centre for Architectural and Urban Studies, University of Cambridge, UK
Abstract This paper proposes that our responses to the environment are influenced in part by our contemporary culture and in part by the genetic background of our primitive survival. Evidence of primitive responses is cited from the fields of thermal comfort, and visual comfort. Strong psychological influences are identified. The need for access and reference to nature in modern life is proposed and the possibilities of other substitutes is explored. Keywords: adaptive, ambience, artificial nature, behaviour, comfort, environment, genetic, primitive, nature, synthetic nature.
1
Introduction
Although we spend 95% of our time indoors, we are really outdoor animals. The forces that have selected the genes of contemporary man are found outdoors in the plains, forests and mountains, not in air-conditioned bedrooms and at ergonomically designed workstations. Fifteen generations ago, a period of little consequence in evolutionary terms, most of our ancestors would spend the majority of their waking hours outdoors, and buildings would primarily provide only shelter and security during the hours of darkness. Even when inside, the relatively poor performance of the building meant that the indoor conditions closely tracked the outdoor environment. Furthermore, many of the activities that played a vital role in survival demanded an intimate knowledge of the climate, the weather and the landscape. Agriculture is an obvious example; rainfall, frosts, wind and their interaction with the landscape – shelter, drainage, pests etc, constantly reinforced man’s link with nature. Robert Winston [1] points out that whilst it is commonly accepted that our physical attributes derive from our primitive ancestors, it is less widely WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060011
4 Eco-Architecture: Harmonisation between Architecture and Nature recognised that our behavioural traits may also. He refers to these as instincts, and uses the primitive model to explain our emotions in relation to families, religion and society. By implication, he is saying that certain behavioural responses are genetically determined and that we could expect these responses to change only by evolutionary mechanisms with a time scale of many hundreds of generations. In this paper we extend the argument to explain our response to our present day built environment – which differs even more from our primitive origins than do our contemporary social and family structures. It is an appealing thought that there is some deep and causal relationship between our adjustment of a thermostat and the action to take refuge from the winter night in a cave; between the tolerance of lower colour temperature light sources at night and the lighting of the multi purpose fire at the entrance to the cave following sunset; between the multi-billion pound industry in cut-flowers and houseplants, and the daily surveillance by primitive man of natural landscape and vegetation. But is there any evidence to support this link, and if it is proven, how will this knowledge help us to understand and improve our modern environment?
2
Thermal comfort
Our modern indoor lifestyle is consuming massive amounts of fossil energy, simply to isolate ourselves from the forces that moulded us. In the last 25 years we have consumed as much fossil energy as in the history of man. Undoubtedly our drive to engineer the environment is broadly the same urge that made primitive hunter gatherer first improve his cave, stockpile food and fuel, then cultivate plants, domesticate animals, form cooperative groups, trade and so on. It seems though, that our technological momentum has caused us to over-shoot; to deliver too much of a good thing, to interpret the life-saving instinct to mitigate the cold by throwing another log on the fire as the need to eliminate all thermal sensation at any cost. To explore this question, we will first turn to the topic of thermal comfort, since both the physiological and behavioural aspects have been well researched. Temperature, or rather the heat balance of the body that it controls, is one of the key environmental parameters affecting survival. We would expect it to be one of the most vital responses hard-wired in our genes. With civilization and development it has lost nothing in its importance, for in struggling to isolate ourselves from the natural variations in temperature, energy for heating and cooling buildings has become the largest single energy end use. The most essential characteristic of the outdoor environment, is its variability. There is variability on different time scales – daily and annual cycles as well as the quasi-random nature of weather, and on different scales of space ranging from human scale to global scale. The consensus view, that supports a massive heating, ventilating and air-conditioning industry, is that the engineer’s proper mission is to provide a stable, optimised environment, independent of the natural world outside.
WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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However, this is being challenged. More than twenty-five years ago, Lisa Heschong [2], in her highly original work “Thermal Delight” decried thermal uniformity. A decade later, this time as a result of rigorous field studies, Schiller [3] concluded that“…people voting with extreme [thermal] sensations are not necessarily dissatisfied”. Since then many field studies have confirmed that thermal variation is tolerated, and in many cases enjoyed. 2.1 Thermal comfort: the two models We have then, two schools of thought – the conventional view that thermal comfort is best described by thermal neutrality brought about by a steady state heat balance, and those that believe that thermal comfort can be achieved within a range of thermal sensations, provided adaptive behaviour is possible. The former school, based on responses of subjects in climate chambers, is epitomised by the work of Fanger [4], whilst the latter uses evidence from subjects in real buildings, typified by the work of Humphreys and Nicol [5] Few would suggest that either represents bad science, yet they seem to reach significantly different conclusions. Why is this? One explanation would come as no surprise, that people behave differently in different contexts. It is not surprising that the subject, who has been told how to dress, been told how to sit, been told what task to do, in an unfamiliar climate chamber with no windows to open or warm radiator to draw closer too, responds differently from a person working in their study at home. The latter knows that there is a cold beer in the fridge or a warm sweater if needed. This has been tested directly by Oseland [6], who observed that the same group of subjects when tested in three contexts climate chamber, workplace and their home became progressively more tolerant - accepting winter comfort temperatures 3ºK lower than in the climate chamber, with an intermediate value in the workplace. The key difference between the climate chamber and the real working or living environment is that in the second case the subject has a range of actions available to him or her that will mitigate the non-neutral thermal sensation. We refer to these actions as adaptive behaviour, and the facility to carry them out as adaptive opportunity. 2.2 Field studies The role of adaptive behaviour in achieving thermal comfort has received considerable attention in the last few years and the importance of adaptive opportunity (figure 1) has been identified, Heerwagen [7],Bordass [8], Baker and Standeven [9]. This is the real and perceived freedom to make adjustments to the local environment (open windows, deploy shades) or to one's own status (remove clothing, move to cooler part of the room, alter posture). Work by Guedes [10] shows that in a large sample of office workers in Portugal, occupants felt more satisfied with the thermal conditions where there were openable windows, even when the opportunity for opening them was not taken. This strongly suggests that there is a psychological as well as physical aspect to adaptive behaviour. We will return to this issue later. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Figure 1:
Two office environments in Lisbon showing good (left) and poor (right) adaptive opportunity.
Even in more extreme climates, adaptive actions are often sufficient to achieve thermal satisfaction for wide ranges of thermal conditions. In a study in the Sudan, Merghani [11] observed that occupants of courtyard houses utilised the spatial and temporal range of temperatures available in the rooms and courtyard to maximise their comfort. Figure 2 shows that the occupant is highly selective; the temperature chosen by an occupant remaining close to the predicted comfort temperature, throughout the day. The migration was not solely comfort-seeking, but was also for practical and social functions. However, habitual use of the house in this way, has a mutually reinforcing effect on these functions, and leads to increased overall satisfaction. This supports the notion that thermal comfort is a strongly contextual and holistic phenomenon. It explains too, why under the closely controlled conditions of a test chamber, subjects respond in a completely different way.
Figure 2:
Chosen temperature (heavy line), i.e. the temperature at the location of the occupant throughout the day, with the range of temperatures existing in the building at each hour indicated by the bar. Note the chosen temperature follows the comfort temperature almost as closely as possible Merghani, [11].
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7
Outdoor comfort
In a study in Cambridge by Nikolopoulou et al. [12], it was found that people sitting outdoors in public places, had greatly increased tolerance of non-neutral conditions, compared to what we would expect for indoor comfort. Typically, satisfaction was around 85% compared with a predicted value of 35%. Note that the predicted satisfaction, using Fanger’s heat balance model, had already taken account of clothing level and metabolic rate, suggesting that there must be a strong psychological factor to account for the wide difference between the predicted and the actual satisfaction. She also observed significantly higher satisfaction when people were free to suit themselves when to leave, than when they were waiting to meet someone. This indicates that the element of choice has a significant and measurable effect. The increase in tolerance was noticeably greater than is found inside buildings, even when they are regarded to have good adaptive opportunity. Could this be because the subjects are in outdoor and “natural” surroundings? Nicolopoulou also found that for subjects suffering from overheating discomfort in a sunlit street, where there was no natural landscape and little opportunity to seek shade, their increased tolerance was reduced. These three examples certainly demonstrate adaptive behaviour, but they do not prove that it is essential for the environmental variance to which the subject responds to be “natural”, although the increased tolerance in the latter case, certainly points in that direction.
4
The luminous environment
Our sensitivity to light is very different from our sensitivity to heat. Light in itself is rarely life-threatening. However, in its role as a carrier of information, it may well become critical to survival. It is not difficult to think of cases where this is so, for both primitive and modern man. Natural light also signals the diurnal cycle of rest and activity, preparing the human for tasks which are most definitely critical to survival. It is well known that exposure to natural cycle of daylight is instrumental in synchronising the body by the suppression of the hormones melatonin and seratonin. But do we find responses to the luminous environment that are directly analogous to the thermal environment? A study carried out by Parpairi [13] in Cambridge showed an unexpected result. She studied user responses to different daylight conditions in a number of university libraries. Two cases are shown in figure 3 below, one, in a study carrel where the illumination is of high technical quality (glare free diffuse light without the distraction of high contrast), and another close to the window where conditions varied strongly with the weather conditions and in particular the presence of sunlight. Her findings show that the preferred condition was the second. Users found that they enjoyed the sunlit view of the River Cam, and if the glare became unbearable, they could retreat into a shaded part of the room (seen on the left of the picture). The building offered adaptive opportunity and in spite of strong WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
8 Eco-Architecture: Harmonisation between Architecture and Nature stimuli of a natural origin, occupants reported a high level of satisfaction. This case does seem to be closely analogous with enhanced levels of thermal satisfaction under similar natural stimuli. However, it is more complex because of the far greater information carrying capacity of light. It is interesting to speculate if the result would have been the same had the idyllic river-scene been replaced by a car-park or rubbish dump.
Figure 3:
Comparison of occupant response environments in two libraries.
to
different
daylight
Clearly the information carried is important, even when it does not relate to the central task. We are dealing with ambience here, and it seems that ambience associated with nature is highly valued. A striking and much quoted study carried out by Ulrich [14] investigated the impact of daylit views on patients recovering from surgery. He showed that patients recovered more rapidly when able to view a middle distance natural scene including trees, than when viewing a blank wall (Table 1). Table 1:
Comparison of requested analgesic doses per patient for wall view and tree-view patients; 46 patients between 2 and 5 days after surgery – R S Ulrich [14]. Analgesic strength Strong Moderate Weak
number of doses wall group 2.48 3.65 2.57
tree group 0.96 1.74 5.39
Even without view, the dynamic quality of daylight seems to have an intrinsic value in the healing process. Keep et al. [15] reports on a comparison between the Intensive Care Units at Plymouth and Norwich. It was found that patients from the Norwich unit which was windowless, had a much less accurate memory of their length of stay, were subject to greater problems of disorientation, and WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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recovered more slowly, although the windows at Plymouth were only translucent providing daylight, but no external view. The intrinsic value of daylight in schools has been recognised for more than a century. In “School Architecture” a manual prepared to assist in the design of urban schools following the passing of the Education Act in 1870, E R Robson [16] says rather poetically - “It is well known that the rays of the sun have a beneficial influence on the air in the room …. and are to a young child very what they are to flowers” Much more recently the value of daylight has also been quantified in the learning environment. In a study carried out by the Heschong Mahone Group [17] in the US, using data from government learning performance tests, it was shown that for 8 to 10 year old children, annual progress in maths and English was improved from 6 to 26% for day lit spaces. The effect was observed where daylight entered via diffuse rooflights, but the largest progress was found where daylight also entered via windows.
5
Biophilia
“I love nature” is a phrase that covers a wide range of emotions. Responses may include a wide range of actions, from hill-walking holidays to subscriptions to the WWF, from designing buildings that look like insects, to keeping indoor plants in the office. But there is one thing in common with these diverse actions, all look outside the species of homo-sapiens and its immediate self-constructed world, for some kind of inspiration or at other times, solace. Is this just to be dismissed as sentimentality? Is nature to be seen important only if it yields raw materials for drugs, food and materials; is bio-diversity to be protected simply for the utility of the gene pool, or is this engagement of deeper significance? In developed nations, many of us live lives highly divorced from what we chose to consider as nature. However almost wherever we look in the man-made world we still see references to nature somewhere. The question that this paper poses then, is should we actively promote and provide this – nature reserves, parks, gardens, … natural materials, climatically responsive buildings … down to indoor plants and pictures of distant mountains on the wall? Or should we simply respond to demand? Should Eco-architecture promote or respond. 5.1 Nature and architecture If we look at primitive architecture there is much evidence of nature incorporated in both the form and the structure of the building. Indeed we can move back from the human being into animal architecture itself and see wondrous forms and intricate skills demonstrated. But it is obvious that the incorporation of a branch or a broad palm leaf or bundle of reeds bound together to make it into a useful element, is not some conscious gesture to represent nature. It is nature itself, because of the lack of anything else. It is adaptive opportunity. Vernacular buildings rarely show “references” to nature in form or element, since, like the primitive shelter, they by necessity incorporate nature. Thus we WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
10 Eco-Architecture: Harmonisation between Architecture and Nature see the timbers of a house with the grain and knots showing – even more impressive, the crook house, where a bent tree-trunk is sliced in two to produce a pair of matching half portals. The thatch, the wattle and daub, the tiles and bricks are all from the locality and would be materials that the occupant understood – trees are felled, reeds are cut, bricks are burnt. There was no need to fashion something to look like nature, it already was nature. By contrast, most people looking at a modern downtown building, would not know where the materials, both on the inside and out, came from or how they were produced. Even modern low rise housing plays tricks on us – slates produced from epoxy resin, autoclaved calcium silicate bricks, moulded doors imitating wood grain, the rooms lined with laminate floor, synthetic carpet, reconstituted stone worktops and sink etc, etc. It is perhaps for this reason, our distancing from real nature, that architects and designers have become so fascinated by mimicry. Unlike the classical column this mimicry becomes symbolic by form only, not by function. Whereas the tubular steel column has a direct equivalent in the hollow stems of plants, and shares the same efficiency of material, many modern architectural manifestations of nature, as illustrated below, are purely symbolic.
Figure 4:
6
Milwaukee Art Museum, Wisconsin, USA by Calatrava. Although seductively evocative of nature the form is symbolic rather than functional.
Implications for environmental design
We have suggested that man has a need for environmental stimuli and a need to respond to them. If this is true, what are the implications for the design of our buildings and cities? We have also implied that these stimuli should be due to ‘natural causes’ and associated with the ‘natural’ outdoors. (But this could be simply because the positive evidence available is only from cases where the stimuli are of that type). And we have referred to this package of stimuli as ambience. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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This prompts the following questions: Is it essential to have natural ambience by contact with natural environmental diversity? Or can we create artificial ambience – where natural environmental diversity is simulated? Or even can we create synthetic ambience – were the diversity is artificial and arbitrary? 6.1 Natural ambience This is the conventional ‘adaptivists’ view. The architectural interpretation is the adoption of shallow plan buildings, naturally ventilated and daylit with openable windows. Controls would be intuitive and sympathetic to occupant participation, and the spatial and technical design would provide variety and adaptive opportunity. Intermediate spaces such as atria, conservatories, loggia and verandas, free from active control, form a soft edge between the interior and exterior. Externally the architecture continues into the garden where the microclimate still shows a degree of moderation and the horticulture is applied with a range of artifice, but ultimately allows nature to dominate. The landscape design is influenced by its perception by the occupants of the building, rather than being seen as a setting for the building when seen from outside. The principle continues at the urban scale, with accessibility of and to wild life considered in the provision of green corridors and wild parks. Although indoors, the occupant is placed in the natural world and the building is seen only as a mediator. And the contextual awareness does not stop at the site boundary; it is reflected in a concern for the global environment – the choice of materials and a responsible attitude to the use of energy and other resources, messages which are implied by the design of the building. Why then, do we have to consider the issue further? Urban growth, the coalescing of communities, seems to be driven by a force as inevitable as the law of gravity. Unlike gravity, it is not described by a simple algorithm – rather it is the result of a complex of political, cultural, functional and environmental expedients – and cannot be discussed here. The outcome however, is relevant, since together with the resulting growth of land value, it has led to an ever-increasing size of building and plan depth. This in itself removes people from the natural ambience of outside. Just as at the end of the 19th century the developing technologies acted as a stimulus to urbanization and the enclosure of the working environment, current technologies offer technical opportunities which creative architects find irresistible. Recent developments in materials such as glass, polymers, stainless steel, in computed structural analysis, and information technology, all facilitate the increase in size and technological complexity of the modern building. Inevitably then, the question must arise – can we do without natural ambience? Can the environmental diversity be delivered in a different way? 6.2 Artificial and synthetic ambience This is nothing new; in a less technological age evocation of the outdoors was provided by painting and sculpture, spanning perceived levels of taste from fine art to the ‘high-naff’ of plastic flowers (with perfume!) and animated pictures of WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
12 Eco-Architecture: Harmonisation between Architecture and Nature waterfalls. With current information technology it would not be difficult to offer a rich menu of naturalistic stimuli – images of landscapes and its inhabitants, sounds and even smells could be delivered deep into a building. This could transport the occupant to distant idyllic environs, or simply relay the real outdoor surroundings of the building. It could be accompanied by ‘naturalistic’ environmental stimuli such as temperature swings and modulations of luminance and colour temperature. Simulation and virtual reality has reached an advanced state of development – now used for applications as diverse as, for example, training in surgery, flying, and presenting building ‘walk-throughs’ from electronic moving images developed straight from CAD packages. Simulation in these circumstances is hugely successful and convincing – it is well known that airline pilots training to cope with emergencies show signs of profound stress although they are quite aware that the circumstances are not real. If this is so successful, would not the evocation of the garden outside be an easy task? But there is a difference here. In the case of the flight simulator, the illusion is the focus of interest. In contrast, the image of distant mountains projected onto the walls of a building, will have to be absorbed subliminally, if it is to achieve the quality of natural ambience. We have made the case for environmental variance and diversity in order to stimulate adaptive behaviour. But does the variance have to relate, either directly or by artificial means, to nature. Could not the thermal, visual, and acoustic environment be modulated in an arbitrary way, and a new set of adaptive opportunities be created artificially? For example a temperature swing could be delivered by the a/c system at the same time that a strong visual event was created by the lighting system. This could then be neutralized by an action through a graphic interface on the occupant’s workstation. Would this synthetic ambiance be as satisfying as walking to the window and throwing it open?
7
Conclusions
It appears then that our instinctive responses to the natural world are alive and well, and still make an important contribution to our health and comfort in the modern environment. However, our cultural responses have to a large part, removed us from the very nature that nurtured us. There seem to be two directions to go – embrace ‘real nature’ – naturally ventilated, daylit buildings, with user-controls, set in an accessible naturalized landscape into which nature is welcomed. Or, pursue an ever more technological approach – controls with automation and IT feedback, simulation, virtual reality – a science fiction future of colour therapy rooms, sensory stimulation scenarios, and personal implants programmed to give the sensation of bird-song and spring sunshine! Indeed, this scenario has been visited by many science fiction writers, one suspects cynically, rather than enthusiastically. If successful, it would give the ‘advantage’ of being able completely disengage from nature – there would be no limit to the height and depth of buildings, and their occupation density. As is customary at the end of scientific papers, we say that there is need for more research. It is hoped that this paper will help make the case for a new WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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field of cross-disciplinary study, bringing physics, biology, psychology and sociology, into the architecture and engineering of the built environment.
References [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17]
Winston, R. Human Instinct. Bantom Press, 2002. Heschong, L. Thermal Delight in Architecture, The MIT Press, 1979. Schiller, G.E., A comparison between measured and predicted comfort in office buildings. Fanger P.O. How to apply models predicting thermal sensation and discomfort in practice in Thermal Comfort: Past, Present and Future, ed 1994. Humphreys M.A, Nicol J.F. An Adaptive Guideline for UK Office Temperatures in Standards for Thermal Comfort – Indoor Temperature Standards for the 21st Century, ed. By F. Nicol, Humphreys 1995. Oseland N.A.1994 A Within Groups Comparison of Predicted and reported Thermal Sensation votes on Climate chambers, Offices and Homes. Proceedings of Healthy Buildings 94, Budapest, 1994. Heerwagen J. Adaptation and Coping: Occupant Response to Discomfort in Energy Efficient Buildings. Proceedings ACEEE Summer Study on Energy Efficiency in Buildings 1992. Bordass W. User and Occupant Control in Office Buildings. Proceedings ASHRAE conference on building design, technology and occupant wellbeing, Brussels, 1993. Baker N, Standeven M. Thermal Comfort for free-running buildings. Energy in Buildings 23, 1996. Guedes M. Thermal Comfort and Passive Cooling in Southern European Offices. PhD Thesis, Univ Cambridge, 2000. Merghani, A. Exploring thermal comfort and spatial diversity. In Environmental diversity in architecture. Ed. Steemers K., Steane M A, Spon Press, 2004. Nikolopoulou M, Baker N, Steemers K. Thermal Comfort in Outdoor Urban Spaces: the Human Parameter. Solar Energy 1999. Parpairi, K. Daylighting in Architecture – Quality and User Preference. PhD Thesis. Univ Cambridge, 1999. Ulrich, R S. View through a Window may influence Recovery from Surgery. Science 224. 1984. Keep P, James R, Inman M. Windows in the Intensive Therapy Unit. Anaesthesia, 35, 1980. Robson, E R., School Architecture, Leicester University Press (1972) 1874 Heschong Mahone Group. Daylighting in schools. California Board of Energy Efficiency. 1999.
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Ecological propriety and architecture V. A. Metallinou Hellenic Society for the Protection of the Environment and Cultural Heritage, Thessaloniki Branch, Greece
Abstract For centuries, building has been seen largely as a way of living apart from the environment and dominating nature. This has turned out to be a pyrrhic supremacy and the current ecological crisis has motivated many professionals and academics to re-evaluate the fundamental premises of how buildings are designed and produced. The potential of buildings to cause global environmental damage was first acknowledged during the 1980s and out of this realization, the concept of “sustainability” emerged which now enjoys a central place in the discourse. There are clear connections between the effects of globalization and architectural practice. There is a direct link between the destruction of the rainforests and how we build and with which materials; and the erosion of the ozone layer has led to a reassessment of how energy is used in buildings. The issues that bioclimatic buildings and settings address are essentially threefold: energy, health and wellbeing and sustainability. Yet, eco architecture is not only a matter of specific design choices that lead (most of the time) to specific high tech building products, but the appropriate mentality that emancipates a specific attitude of dealing with building within nature. In doing so, regional and national planning should surely lay emphasis on maximizing ambient energy and at the local level, planning should strive to increase density in urban areas to combat the increasing suburbanization, as a means to protect surrounding nature - the raison d’ etre of the city. To Vitruvious’ Firmitas, Utilita and Venustas (strength, functionality and beauty) a further criterion has to be added - restitutes (restitution) in which the act of building enhances the environment in an ecologically responsible manner. Keywords: globalization and architectural practice, building and energy, building within nature, eco-architecture, energy, health and wellbeing and sustainability. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060021
16 Eco-Architecture: Harmonisation between Architecture and Nature
1
Introduction
For centuries, building has been seen largely as a way of living apart from the environment and dominating nature. This has turned out to be a pyrrhic supremacy and the current ecological crisis has motivated many professionals and academics to re-evaluate the fundamental premises of how buildings are designed and produced. Underscoring technical efforts to reconstitute the built environment is the elusive but critically important concept of sustainable development. Across a wide range of disciplines including architecture, a new attitude, conjecturing a built environment that mimics and complements rather than conflicts with nature, is emerging, as a vital goal of current theory and practice. Notions of sustainability are not a preoccupation of recent history. The medieval monasteries of Europe and in the Balkans, led their unique ecological paradigm centuries ago. They produced their own food, created buildings from local materials, captured and recycled water and developed renewable energy technologies such as water and windmills. These highly structured societies, took care of the sick and elderly, cultivated land according to ecological principles and had a humane approach to animal husbandry. Such practices still obtain in rural communities in Latin America, Africa and Asia and often appropriate selectively aspects of contemporary technology. For instance, in the desert regions of North Africa, doctors still travel by camel to visit remote villages. It’s a tableau unchanged for generations, but nowadays the camel is equipped with a GPS antenna on its head to signal its geographical position, and a photovoltaic panel on its back that provides energy to run a fridge containing medicines to treat the sick. This instinctive, almost poetic synthesis of tradition and technology could have wider implications for the sclerotic First World, as “sustainable development” is not a term one hears in such settlements, but in reality, these are places from which the rest of humanity could usefully draw lessons rather than seeking to “improve” them. There is a danger of a nostalgic glorification of some isolated, eco – responsive aboriginal society, totally removed from our debauched, technologically sophisticated milieu. On the other hand, the lessons of these civilizations and their cosmology reveal a wealth of insights into the evolution of the human habitat that cannot be ignored. They provide instructive examples of how to deal with climate and demonstrate ideas, attitudes and lowtech solutions that can be usefully incorporated into contemporary shelter. Equally importantly, these cultures offer the basis for rethinking humankind’s relationship with the planet.
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The line of history
In the Pioneers of Modern Design, Nikolaus Pevsner identified the Arts and Crafts Movement flourish in Britain in the decades either side of 1900s, as one of the major influences upon the emergence of the Modern Movement.
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In the ideas of William Morris and their translation into architectural form and language is possible to recognize antecedents of Modernist Architectural theory and practice. Morris’ theories established the principles of fitness for purpose and the integrity of materials as a fundamental importance in the design of all articles of use. To these, architects of the Arts and Crafts Movement added a sense of response to place in applying Morris’ ideas to the design of buildings. In their specific interpretation and application of principle, they placed particular emphasis upon the question of orientation in determining the placement of buildings and particularly houses upon their sites and the position of the principal rooms. More over, with the use of the bay window, they concentrated the main areas of glazing towards the sun. The environmental credentials of this architecture extend beyond observance of orientation, into a complex and subtle setting for domestic inhabitation. Spaces may be closed-off or opened-up in response to environmental and social requirements and the garden is consistently conceived as an essential complement to the interior spaces and not as an added-on afterthought. In more modern terminology, what we find here is an environment which is climate-responsive, spatially and temporally diverse, user-controlled, adaptable and sustainable. We also perceive a conception of nature of architecture that predates the reductive processes of 20th century, in which questions of environment are comprehended within an all-embracing synthesis of the cultural, social, technological and aesthetic. By the late 1920s, the events traced by Pevsner in the Pioneers, had led to the transformation of the language of architecture from a traditionally grounded synthesis to a new analytical clarity - the Modern Movement. The methods of architectural science in the application of quantified standards in the functional needs of buildings and their users attract particular interest in the relationship between design and the environmental principles, where quantification is placed in the context of a particular vision of the wholeness of architectural enterprise. As the idea of research mainly took roots in schools of architecture, so environmental studies started gaining importance among the academia as well as in policy making bodies. The continuity of the field in which we all work, is expressed clearly in the discipline of the philosophy of science of the era. Thinkers such as Karl Popper and Thomas Kuhn describe the way in which science proceeds systematically within the discipline of prevailing paradigms, using rigorous procedures and accumulating a body of knowledge, which serves the solution of new emerging problems. The hypothesis of research programmes, introduced by Imre Lakatos was used as the core theory for proposing in the 1980s the Architectural Research Programmes as the way to understand the development of our discipline—Stanford Anderson - Vivianna Metallinou Libero Andreotti, MIT, 1982. The whole enterprise made possible to bring into focus all of the variables and processes which occur in the environmental system of a building along with the central role of the occupant and the contextual studies of the special relation between site and building, prepared the way of
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18 Eco-Architecture: Harmonisation between Architecture and Nature architecture to take advantage of theory and practice in the environmental research (Regionalism and so).
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Sustainability and architecture
With the energy crisis of the 1970s, the issue brought into focus was the relationship of environmental design to the energy demand of building. From this, a new parameter entered the equation of architecture: the concern to explore the relationship between the form and materiality of buildings and their energy consumption. Physical, mathematical and computer modeling of building environment in the architecture schools, proposed either quite simple graphical representations or experimental structures for use by designers. Terms such as “low-energy architecture”, “passive solar design” and “bioclimatic architecture”, entered the lexicon and importantly, redefined the agenda of both research and practice. The potential of buildings to cause global environmental damage was first acknowledged during the 1980s and out of this realization, emerged the concept of “sustainability” which now enjoys a central place in the discourse. There are clear connections between the effects of globalization and architectural practice. There is a direct link between the destruction of the rainforests and how we build and with which materials; and the erosion of the ozone layer has led to a reassessment of how energy is used in buildings. Architects, however, are dependent on other bodies for the gathering and assessment of data, for the analysis of causes of degradation and for proposals for its reversal. These bodies come in various forms: international agencies (the Club of Rome) national ministries, research institutes, non-government organizations NGO, independent consultancies and individuals. It is left to the architects to make sense of it all, in the context of a building where energy and environment may be seen as important issues, but where there are other equally important requirements (from the client) and where at the end of the day the building must be a complete architectural statement. It has been said that architecture is the mother of the arts, thereby claiming for it both maternal and aesthetic ascendancy. If this is so, the matriarch in architecture holds in balance the well-being of another mother figure: MotherEarth, while the art in architecture, uniquely has to meet the complex demands of use as well as transporting the senses. It is on the relationship of these two roles architecture as an art of function and architecture as environmental custodian, that the whole discussion is focused. Bioclimatic architecture is seen as a reaction to the predicament of environmental depredation in the same way organic farming is a reaction to the dominance of intensive, chemically based agriculture. And worthy but dull enough it is positioned at the fringe of the main production. The attitude to attain yet the form of another movement leads it to another categorization that separates and marginalizes it again.
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The proposal
… “In doing a memorial I started with a room and a garden. That was all I had. Why did I choose a room and a garden as a point of departure? Because the garden is a personal gathering of nature and the room is the beginning of architecture” starts Luis Kahn in his “Between Silence and Light”. The dialogue between architecture and nature is as old as architecture itself. It is only in recent history that this happy interaction has been extinguished. Until then, both aesthetic and functional attributes of architecture were inextricably linked to nature. Seen as such, bioclimatic architecture represents an overdue return to and a broadening of the innate and continuing exchange. It lies squarely in the mainstream of architecture and is neither expedient reparation nor arcane cult. Architecture is depended on a satisfactory reconciliation of the intuitive with the rational. A building has to be both a poem and a machine. Yet, few buildings achieve such a status. There are those that are sensually stimulating but lack sound construction and those that answer successfully practical needs but fail to generate an emotional charge.
Figure 1. Axiomatic to arriving at an inspirational balance between sense and sensibility are two relationships: that of building to site and both of these to nature itself. The capture of the genius loci is the content that makes a chosen site special and distinctive. The relationship of building and site to the wider natural environment is again subject to the intuitive and the rational. The art of architecture therefore, has to embrace both the inspirational and the analytical and architectural response to our environmental predicament will also reflect this dichotomy.
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20 Eco-Architecture: Harmonisation between Architecture and Nature
Figure 2. …“First we had nature. And then came the Environment. Environment is the smoke, humanity has put on nature: the people who used Latin had no word for environment- they only knew natura” [1]. It is more than obvious that we have to agree on what we mean by the newly defined terms of our discussion. Both environment and sustainability mean numerous and different things. What we refer to as bioclimatic is an approach to design that is inspired by nature and which applies a sustained logic to every aspect of the project, focused on minimizing environmental depredation and encouraging a sense of well-being. The issues that bioclimatic buildings and settings address are essentially threefold: energy, health and wellbeing and sustainability. A key aspect in designing a bioclimatic building is determining its comfort criteria, as perception of comfort varies considerably from individual to individual and between ethnic groups who become more habituated to local climatic conditions. It also varies between countries and continents according to the level of development each of them is having. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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The extraction of potent architectural expression from underlying social theory and technical innovation is the stuff of architecture and as noted, a characteristic of mature bioclimatic architecture.
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New partners on design
Architecture as a discipline to itself is only one facet of the issue. In the 2002 UIA World Congress in Berlin, the main theme elaborated by the organizers was that architecture is subjected to take into direct consideration the growing importance of new technology in building methods as well as the new materials available in the market. As a result of that, even from the time of the idea elaboration, architecture is the outcome of a team - work between architect and the building contractor (or company) and the scheme has come over to embrace the whole design process. We still enjoy architecture in the Bazaars of Architecture – the cities as the theme of the last UIA 2005 World Congress in Istanbul presented, with the unrivaled star system architecture to claim one aspect of the production and the Euphoria Manifestoes on the other hand to return the discussion on the sustainable aspect (Richard Senett). The growing sensitivity and public interest, to the appreciation of cultural heritage that is being extended to include and embrace all interesting manmade structures since the last decade, is shaping another strong aspect on the issue of sustainability on architecture. Networking in the field of heritage is a practice that strengthens attitudes towards the appreciation and use of culture as a driving force for shaping the present. Fighting for the preservation of the cultural heritage of one’s millieu, helps shaping the appropriate mentality for an eco attitude at first, which will be followed by eco-architecture, eco-mechanics, ecoagriculture perhaps. Sustainability considered from this point of view, functions as a means of cultural consistency. Design gains a meaning as a chain of cultural continuity and linked to the social development policy. Within these qualities, the sustainability can be interpreted: • As a means of integration between society and the profession • As a means of surviving the cultural values and tradition • To make the user an effective part of the design process • To improve the communication among different disciplines and scientific fields The important point is to bring together the civilian contribution with the idea of ecology and to initiate the participation and support processes on the issue. When developed with a method that can be used as a platform to raise the voice of the free thought, this initiative will become a contribution for the culture of democracy and will propose a reform process in the field of interaction. The sustainability approach is before all a reform process in thought. Like any other processes it necessitates a political choice or stance. The most significant determiner is the logic of the process and therefore it is inevitable for the economic and political powers to exist in this transformation and reproduction process determinedly and take the necessary responsibility. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
22 Eco-Architecture: Harmonisation between Architecture and Nature Against the multidimensional erosion emerged with globalization and spread to several fields, the attitude of the architect and designer gradually gains significance and their political choices can become a determining factor for the process. Eco architecture is not only a matter of specific design choices that lead (most of the times) to specific high tech building products, but the appropriate mentality that emancipates a specific attitude of dealing with building within nature. Coming from a country known for the specific quality of place, I believe that eco architecture has above all to submit seriously to the attitude of the protection of everything that lays there, in order to keep trace of a development that need not research booths to come up with the proper and right. In doing so regional and national planning should surely lay emphasis on maximizing ambient energy while at local level, planning should strive to increase density in urban areas to combat the increasing suburbanization. Architects must provide geometries of living that offer density with the advantages of suburban life. A thorough understanding of the principles of passive and active energy conservation should be expected and we should add to Vitruvious Firmitas, Utilita and Venustas (strength, functionality and beauty) a further criterion for judgement of architecture – restitutes (restitution), in which the act of building enhances the environment in ecologically responsible manner. The line I am drawing here is a paradigm from the holistic traditional procedures, indicating the uninterrupted continuity of the field in which we work and demonstrating the prevailing belief that the problem can be dealt on. By exploring notions of appropriate rather than high technology and create buildings that are not only harmoniously integrated with the landscape but also climatically responsive, embodying the soul and substance of an emerging ecological propriety that gives great hope for the future in a humane, inventive, radical and passionate architecture that acknowledges the world beyond the glossy magazine pages. We, architects, cannot transform society, but we can certainly transform architecture. And by doing so, we will change other forms of production too.
References: [1] [2]
[3]
[4]
Metzger Gustav, Symposium on Sustainability, The Architectural Association, London, UK. 1996. Dr. Incedayi Deniz, Sustainability as a form of conduct in the context of environmental sensibility, proc. of the 1st international conf. of architects “Architecture and sustainable development on the Balkans”, Sofia, pp 19, 2004. Dr. Slaev Alexander, Balkan architecture and architects – working towards sustainable development of southeastern Europe, proc. of the 1st international conf. of architects “architecture and sustainable development on the Balkans”, Sofia, pp 19-26, 2004. Davey Peter, Designing our future, The Architectural Review124, pp 2627, January 2001. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Architecture and nature at the end of the 20th century: towards a dialogical approach for sustainable design in architecture F. J. Soria López Metropolitan Autonomous University, México City, México
Abstract This essay approaches architecture from a humanist point of view, analyzing social dialogue in relation to design processes and architectural production, which search for a balanced interaction between the built environment and its natural and cultural settings. In a first approach architecture is considered as a ‘second nature’, one that is fit to meet man’s needs, which goes beyond functional and pragmatic issues, and include in a fundamental way the spiritual aspects, those which ultimately define our human nature. In a second phase a historical-interpretative analysis is developed for a better understanding of the main practices in sustainable architecture over the last two decades of the 20th century. The concepts of dialogism and the hermeneutic trilogy (pre-figuration, con-figuration and re-figuration) developed by M. Bajtin and Paul Ricoeur, respectively, are explored as a methodological structure to analyze and interpret a sustainable architecture. The idea is to bind dialogism and sustainability as one concept, in order to approach architecture in an integral and holistic way, and to try to visualize it as a multidimensional cultural phenomenon. Here, the main hypothesis is explained, one which establishes that both, biophysical and tangible factors, as well as social and intangible ones, are indispensable cultural parameters to consider when designing a truly sustainable architecture. Keywords: dialogical sustainability, sustainable architecture assessment, second nature, dialogical architecture, sustainable architecture, qualitative interpretation of space.
1
Introduction
During the 20th century contemporary society experimented diverse and profound transformations in the way its individuals communicate and relate with WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060031
24 Eco-Architecture: Harmonisation between Architecture and Nature one another and with their surrounding environment, like never before in human history. Particularly in the last few decades the relation between man and nature has acquired great importance in our social conscience as we become aware how human action and production are progressively devastating the natural environment. In an intent to stop this environmental impact that affects the world as a whole, a great number of countries have adopted since the end of the 80’s (Brundtland Report 1987) and the beginning of the 1990’s (Earth Summit 1992) the concept of sustainable development defined as that social, politic and economic development that meets the needs of the present without compromising the ability of future generations to meet their own needs, as a way to reach a better quality of life for all societies and simultaneously preserve the natural environment. Aware of this emerging problem, architectural practice has “reacted” strongly, and in the last few years we have seen many possible solutions: ecological architecture, green architecture, bioclimatic architecture, energy efficient architecture or simply sustainable architecture. This last term tries to gather all the previous design processes which incorporate strategies to evaluate, control and minimize the physical impact of the building on its surrounding environment. After making a critical analysis of the leading stances, it seems evident that these “sustainable” practices are dominated by a sort of scientific or environmentalist posture, that understands architectural design as subordinated or dominated mainly by external relations: that is, physical, tangible and quantifiable conditions, adopting certain pre-established parameters such as form, maximum contamination rates, energy standards, etc. This posture seems to lead to an “ecological determinism”, when designing cultural objects with much more complex characteristics.
2
Sustainable architecture or environmental engineering?
In the past few decades the main environmental design processes in architecture and most of the normative regulations applied focus on diminishing the ecological footprint (not interrupting, modifying or destroying natural ecosystems) and are sustainable as long as they use, within certain limits, the natural resources (renewable energy, biodegradable materials, residue treatment) intended basically to reduce its physical impact on nature, at both local and global levels. On the other hand much of the literature, as well as many educational programs about green, sustainable, environmental or ecological architecture talk about the urgent need to “establish a new relationship with the natural environment” [3] as part of the responsibility of the architect that must not be delayed; nevertheless, they concentrate their analysis, precisely on this biophysical impact I have mentioned In this context many doubts and controversies appear in the architect’s work and his duty to the natural environment. At the same time, it is necessary to ask what ethical implications the architectural project has with man himself and the community of which he is part, and, ultimately, to whom architecture gives WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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shelter. What exactly does sustainability mean in the architectural arena? What duties or obligations do the architect and his project have to the nature and culture of the place where the project is set? Is it because of the great deterioration of natural conditions as a whole that these issues should pre-determine the architectural object? Is it correct to speak of a sustainable architecture when biophysical and ecological aspects are first in line, over its social and cultural characteristics? This gives way to an important paradox. Those who strongly support sustainable practices from the dominating biophysical standpoint criticize the cultural stances for being anthropocentric. These stances put human needs (intangible, spiritual, symbolic) above the natural laws that govern logically all ecosystems, of which man is one of many parts. However, the idea of considering nature before human needs is, in itself, much more anthropocentric than it seems at first sight, given that what is at stake is the survival of all natural ecosystems, including mankind. Even those apparently extreme stances - on one side the “naturalistic” point of view, and, on the other, the “scientific” posture, which both defend the radical conservation of nature- represent a materialistic approach. What happens to the human part, the part that distinguishes human nature, that gives meaning to life, that goes beyond our need for solely biological survival, and values nature for what it represents, creates, inspires or motivates. Is not this part of human “survival” also one of the basic needs that architecture has to satisfy? Why should we conserve nature? Is it because, in doing so, we contaminate less and guarantee human survival, or is it simply because we find immense beauty, aesthetic delight, or profound peace in nature that is worth experiencing? Looked at in this way, the biophysical stance, a materialistic approach, seems much more anthropocentric in terms of searching for a concrete and tangible benefit for mankind. The cultural stances, on the other hand, might be more romantic and idealistic, but much more respectful of nature, in considering its existence in its own right. The mentioning of all this leads us to question the specialization in architecture where a sort of environmental engineering is being applied. This specialization promotes the use, organization, management and reproduction of the natural environment in a more technical and efficient way. However, architecture that creates places for human dwelling that, as Le Corbusier believed, must provoke emotion and not just be functional, also relates man with nature in much more profound ways because of its beauty, its texture, its history, its meaning, its color, its smell - all of these possible thanks to man’s ability of conscious perception. What I am trying to emphasize is that sustainable architecture should depart from man, from his needs, his experience, his perception, memory, beliefs as an individual and as a society and, at the same time, from the knowledge and valuation of the ecosystems, the biophysical features of nature and landscapes that we use and, especially, from the relationship between them. This does not imply an anthropocentric vision. On the contrary it may be the way to achieve real possibilities for the conservation of nature through a more conscious and WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
26 Eco-Architecture: Harmonisation between Architecture and Nature informed experience of its presence. I believe, as a hypothesis for the moment, that sustainability in its present terms will contribute to separate man and nature by dominating and exploiting nature in a more rational way. Even if we are able to reproduce all natural systems some day and are able to guarantee human survival, then nature will have ceased to exist and only man, that is artifice, will prevail.
3 Towards a dialogical sustainability in architecture This essay focuses on the always polemic encounter between the built and natural environments, seeking to establish that architecture’s role is to relate physically, but mainly in a cultural way, man and his natural settings. The idea is that man’s intangible perception of and experience with nature, be it poetic, symbolic or abstract, are as important as preserving all its biophysical potential. So, if we consider that the main practices in sustainable architecture in recent years are dominated by ecological parameters as well as the technological paradigm, the central thesis that this investigation explores is that a dialogical design process relates natural conditions (physical and tangible) with human factors (subjective and intangible) on a mutual and equal basis by considering them as indispensable socio-cultural needs for a sustainable architecture in the present and in the future. A dialogical vision of architecture, of sustainable development itself, takes a main role when proposing to transfer the Bajtinian concept of dialogue, understood as the most important way in which individuals of a specific society communicate with each other - that every individual expression is the result of an intense interaction and synthesis of various ‘voices’ from our past and present as a model to analyze architecture and to try to build a bridge between man and nature and, in this way, through the recognition and evaluation of the ethical, logical and aesthetic dimensions of an architectural whole, seek to understand its role as the dwelling space of man and to try, in Bajtin’s words, ‘to discover the interior unity of meaning’ that sustains a building in a specific place and culture: The dialogical analysis of architecture discovers it as a bridge between social sciences and physical sciences, or social history (history) and the history of earth (cosmology). This bridge cannot be insensible to human need and to human survival(…) it should include social needs for survival: peace, beauty, life, health etc. Physical dialogue is insufficient, we also need social dialogue [4]. How does architecture respond to this ‘dialogical’ world and not as a mere ‘thing’, to put it in Bajtinian terms? The main argument to defend this approach in architecture is to take the original dualistic start point between the natural and the artificial: real space, cosmic time get to “be” because there is, in the first place, a consciousness of its existence (subjective), and, after that, a communication of that existence (inter-subjective); simultaneously, there is a positioning of ‘myself’ in relation to ‘us’ and to an ‘other’ inside this objectified WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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world. In this way, a represented world is added to the real world, and to cosmological time, a historical time appears. These are categories that define human culture, thanks to our double ability of consciousness and communication, of interpreting and dialoging, beginning an always unfinished chain of listening- understanding-responding process. Using this conceptual framework, the main objective is to try to build into the dominant trend of environmental sustainability in architecture a dialogic approach. In this approach subjective perception and experience and the collective and inter-subjective valuation of nature as a physical and tangible existence as well as metaphysical and intangible presence are considered as indispensable parameters for sustainable design. Nature is still the main actor, architecture the means to speak with and about her, not only as something given of immutable laws, geological time or ecological processes, but also as a being in and of itself of changing values, as container of experience through collective memories, of creative inspiration, in other words, as a unity of materiality and meaning. S. Kellert [5] establishes quite clearly that sustainable, green or, in general, ecological building processes “will not achieve its full promise and potential until it more positively motivates individuals, developers and planners by capturing in the built environment the widest range of physical, emotional, and intellectual values of nature”. This integral concept has also been proposed in similar terms by different authors, agreeing in the first place that architecture is a complex mix of aesthetic, ethical and logical factors. Thompson [6] proposes a system of ethical and aesthetical values for landscape architecture, and names them as a trilogy among the aesthetic, the social and ecology. With this in mind he establishes that there is univalent design (what we’ve called monological design as opposed to a dialogical one), those who work around one of the three components; bivalent, that includes two of the possible architectural dimensions; and, of course, trivalent design, that includes all three. A closer idea to the concept of dialogue is explained by Benet et al. [7], establishing that there is no one style or kind of design that can be described as truly ‘sustainable’, nor is there a process or method that can guarantee an optimal design because architecture, being a cultural product, must be judged and assessed as an integral unity that has multiple objectives and origins. Trying to overcome these difficulties in this sustainable framework, they consider sustainable architecture as a responsive cohesion: an answer to different participants or stakeholders (user, nature, future generations, program etc.); cohesive because it includes, balances and orders in the architectural object all these answers. But one thing that they do believe is important is the order these dimensions should have, giving ecological processes first place, then the social. This, I believe, is contradictory to a responsive attitude, where the dialogue itself between stakeholders, participants or general conditions of place, is what establishes, in each specific situation, the best possible answer and order. They conclude the following idea:
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28 Eco-Architecture: Harmonisation between Architecture and Nature So after all there is nothing unique about how we should approach the making and identification of sustainable architecture; this is the way good design should be (…) it is [sustainability] a reconceptualization of architecture in response to a myriad of contemporary concerns about the effects of human activity [7]. Thwaites [8], on the other hand, uses the expressivist theory as a conceptual framework in order to evaluate the relationship between architecture and natural environment, not only as a physical product, but also as a way through which man expresses creative desires and aspirations. Again, we can see this fundamental idea of a human communication process: “In this context, design is a means of conceiving and communicating ideas: a dialogue rather than simply a method for solving specialized site-based problems, or specifically for prescribing style”. So, if these ideas, are apparently quite clear in accepting the multiple characteristic of all context with cultural and biophysical components, why speak of this urgent need to change towards a sustainable architecture? Sustainable architecture should not tend, in my opinion, towards an environmental engineering or management methodology, what Thompson describes as univalent design (monoligic); instead it should defend and improve its integrative process, trivalent design, topogenetic dimensions, dialogical approach; in other words, it should be sustainable in relation to the individual who dwells, to society that produces, and to the natural setting that allocates architecture. The main idea is not to describe how architecture is incorporated into nature, but rather how man relates to nature through his architecture. Dialogic architecture recognizes the singularity of each project and of each built place, not as an experience or object isolated from history or social life, on the contrary, as dimensioned and materialization of aesthetic, scientific and political values of a same and specific social dialogue, and because of this universal and permanent [9]. We can understand, then, this “integral sustainability” as the satisfaction of bio-physical and socio-psychological human needs that allow the preservation, use and experience of nature through architecture, focused on improving man’s quality of life without reducing future generations’ possibilities to live with these same conditions and enjoy a rich, beautiful, creative, interesting, clean, healthy and balanced environment In short, architecture, in order to be sustainable, that is, really sustainable and simply good, must satisfy simultaneously all architectural dimensions: logical (science, technical, functional) ethical (security, low impact, protection, good use) and aesthetic (beauty, meaning, emotion) dimensions. 3.1 Dialogical assessment In the last few years sustainable architecture assessment systems have achieved great importance, not only aimed to measure the environmental impacts of the WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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building, but also as tools that help establish strategies and make better decisions in the design process. Nevertheless, it is very important to point out that most of these methods concentrate on the physical impacts on the natural environment. In a relatively recent investigation many of these assessment programs applied in the UK, USA, Norway, Sweden and France were reviewed, concluding as one of their main problems, the following: However, none of the systems reviewed [BREAM, LEED, ESCALE, Ecoprofile, Ecoeffect] in this paper includes social and economic indicators of sustainability; all concentrate on physical and environmental aspects of sustainability [10]. Most of these tools are essentially quantitatively orientated, assigning grades or points, usually with a numerical scale, sometimes of appreciation (bad, regular, good, very good, excellent) to determine the building’s environmental performance. We are back to the main thesis I am trying to defend: sustainability is a way, a means to achieve a better life quality for society as a whole, not a goal in itself. Architecture must take into account its responsibility to the ‘direct’ users of the building, to those who live and use it, to those who perceive it as part of the city on a daily basis, in other words, as part of their daily environment. What kind of impact does the building have on the inhabitants? In which ways does architecture relate the users with the natural surroundings in tangible and intangible ways? The difficulty is evident. There are no recipes or methodology that guarantees a predetermined result. Even if we could have a ‘total’ assessment system that takes into account all the variables, all items, it could become a way to guide, control and determine the results. Probably the best idea is to maintain diverse and different possibilities of evaluation and interpretation - some orientated to the tangible values, others aimed at explaining the meaning or the subjective perceptions of a place- in order to keep the many points of view that contribute to understanding our polycentric reality. Complementary assessment methods focused on the human dimension of sustainable architecture in order to understand and interpret intentions, values, experience, perceptions of nature through our built environment, seem necessary. Cole [11] points out this issue quite clearly: “Environmental assessment methods must accommodate both quantifiable performance criteria (such as annual energy use, water use, or greenhouse gas emissions) and more qualitative criteria such as the ecological significance of the site (…) the qualitative criteria can typically only practically be evaluated on a ‘feature specific’ basis…”. With this in mind, the proposal of this investigation is to outline a dialogical assessment method for sustainable architecture. This method can be a tool to help in the understanding of place by interpreting the communicative process that architecture, as material space, and people, through social use of architecture, establish with the natural environment. The idea is that a dialogical architecture must engage in this communicative process, and RESPOND to the “voices” of the natural and cultural context, demonstrating a listeningWIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
30 Eco-Architecture: Harmonisation between Architecture and Nature
DESCRIPTIVE PROCESS FORM
Social-physical context
USE
Prefiguration
Configuration subjective perception
Refiguration shared experience
VALUATION PROCESS USE+FORM
3
RD
LEVEL
2
initial intentions
Figure 1:
Social value of the architectural object
(VARIABLE OVER TIME)
CREATIVE PROCESS
INTERPRETATION
(Natural and cultural environement) object architectural
ND
LEVEL
1ST LEVEL
understanding-answering process that adds a new portion to the dialogue, always unfinished, that human development implies. In first place, dialogue with the natural settings can be registered through the interpretation and valuation of the experience and perception that the inhabitants have through the use of an architectural space. It is in the dialogue between object and subject, thanks to the dialogical significance that society imbues to nature and architecture, that we value, understand, use or visualize them. On a second level, a dialogical architecture can be defined by relating and comparing the initial intentions that the architect incorporates into the project (by listening-understanding-responding to the ‘voices of the natural and cultural context’) with the experience of the users of the real place. The main objective is to detect the inter-subjective dialogue (architect and user) that architecture makes possible, focusing on the natural settings of the environment. With these parameters, a good architecture, an integral sustainable architecture, allows an intense, interesting and satisfactory experience of the natural factors of the place, an intentional situation that is anticipated by the project, not as imposition, but rather as possibility.
(humanist and materialistic)
Dialogical assessment model for sustainable architecture.
Figure 1 explains the interpretative process that is proposed: a first level that has to do with the description of the place, the architecture, the settings -basically the form and material characteristics; in second place, the evaluation of the whole creative process, that is, the architectural project that contains the initial intentions of the designing team and or participants (prefiguration of place), the experience of the built place on a subjective, that is, individual scale (configured place), and finally, the inter-subjective experience of the place verified by social use and communication (refiguration of place); in third place, the valuation of the former two experiences that conclude in a general interpretation of the human dimensions of architecture, an interpretation that is constantly changing over time. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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3.2 Dialogical architecture In modern architectural practice there are many examples of this capability of reading, listening and responding in an integral manner, based on an architectural tradition that knows how to listen, understand, interpret and, of course, answer the best way possible in that specific moment. Just by naming Gaudí, Aalto, Wright or Barragan we can exemplify this practice. But even today, we may see extraordinary examples in this sense. Analyzed with this dialogical approach, environmentally responsible architecture designed by architects Zumthor, Miralles and Pinòs, Schjetnan and Latz, are understood and enjoyed in all their architectural quality. Far from finding how they are similar in their relation to the place, the immense and rich differences that characterize each one emerge as possibilities of experience, never as predetermined experiences between man and nature. With this dialogical approach it is possible to sense how Zumthor’s thermal baths in Vals is more aesthetically strong, where nature is experienced in a kind of phenomenological poetry, taking direct advantage of the extraordinary features of the natural landscape. Miralles and Pinos Igualada Cemetery recreates nature through an architecture that delivers a more metaphysical and introspective perception, firmly anchored on archaic beliefs of life and death. In Duisburg, the factory’s structure of an old industrial ensemble, clearly identified as the destroyer of the environment, proposes new ways for the machine and nature to relate, without destroying one another, a sort of ethical compromise that P. Latz and his design team clearly assume. In Xochimilco ecological park, on the other hand, the structure is the underlying nostalgic replenishment (nostalgic in the Barragan’s sense, that is, the consciousness of the past, but elevated to the power of poetics) restoring an ancient interaction between society and natural settings, deeply rooted in collective memory.
Figure 2:
From left to right: Vals Termal Baths, Igualada Cemetery and Xochimilco Ecological Park.
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32 Eco-Architecture: Harmonisation between Architecture and Nature Each one is specific, all contribute to conserve the physical environment (the materialistic evaluation was quite constant in all four projects), there is richness in that there was concentration on the the less tangible relations that these architectures provoke between man and nature. It is this dialogical approach the means that help interpret and value the physical and intangible relationships with nature of a specific site.
Figure 3:
Duisburg Landscape Park.
In this perspective, the responsibility of the architect should be, in any case, inclusive, open to dialogue, open to as many possibilities, including, of course, the environmental degradation that worries modern society so much. In short, architects should incorporate the natural in a fundamental manner into their project in order to affect mind and body as a way to improve and intensify our relationship with nature, through architecture - an experience that might be an important way to increase society’s awareness of the urgent need to preserve and respect nature.
References [1] [2] [3] [4] [5]
Bajtin, M.M.; The Dialogic Imagination; University of Texas Press; Austin, 1998 Ricoer, Paul; Arquitectura y Narratividad; In Arquitectonics. Mind Land and Society. No. 4 Arquitectura y Hermenéutica; Edicions UPC, Barcelona, 2003 Luxán García de Diego, Margarita; Arquitectura de vanguardia y ecología ; In: Ciudades para un futuro más sostenible Boletín CF+S. Número 5. Abril 1998.Madrid. http://habitat.aq.upm.es/boletin/n5/amlux.html Muntañola, Josep; Arquitectura, modernidad y conocimiento; Arquitectonics; Edicions UPC; Barcelona; pp.143, 2002. Kellert, Stephen R. Ecological challenge, human values of nature, and sustainability in the built environment; In: Kibert, Charles; Reshaping the built environment. Ecology, ethics and economics.; Island Press; Washington D.C.; pp. 40, 1999
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[6] [7] [8]
[9]
[10]
[11]
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Thompson, Ian; Ecology, community and delight. Sources of values in landscape architecture. E & FN SPON; London. pp 178-179, 2000. Benet, Helen; Radford, Antony and Williamson, Terry; Understanding sustainable architecture; SPON Press; London; pp.126, 2003. Thwaites, Kevin; Expressivist Landscape architecture: The development of a new conceptual framework for landscape architecture; En revista Landscape Journal; Vol. 19, No. 1-2 2000, University of Wisconsin Press, Madison; pp. 207, 2000. Pol, Enric et. al.; La evaluación post-ocupacional (POE) de edificios, una reflexión crítica de su uso: nuevos criterios de sostenibilidad; En Ciudad y Medio ambiente desde la experiencia humana.V Congreso de Psicología Ambiental; Universitat de Barcelona; Barcelona, pp. 240,1996 Crawley, Drury et. al.; Comparative assessment of environmental performance tools and the role of the Green Building Challenge; Building Research & Information; Special Edition, Vol. 29, No. 5; pp 340, Sept-Oct 2001; Cole, Raymond; Environmental Performance of buildings: setting goals, offering guidance and assessing progress; In Reshaping the built environment. Ecology, ethics and economics. Island Press; Washington D.C.; pp. 286, 1999.
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The keyword is quality not ecology A. van Hal Delft University of Technology, the Netherlands
Abstract The Netherlands has a good reputation abroad as a country of architecture. Many people admire the architecture of famous Dutch architects such as Rem Koolhaas, MVRDV, Neutelings Riedijk and Meijer and Van Schooten. In some recent designs by members of this conceptual-oriented school of architects, several efforts have been made to become more in harmony with nature, e.g. by minimising the use of energy. Alongside this school another trend has developed over the last few years. Customer requirements have become more dominant, driven by the recent economic recession, and in many cases this has led to a more pragmatic type of architecture. This pragmatic approach, in combination with the objective for quality, has led to a new school within the Dutch architectural community. In some recent renowned designs of members of this more pragmatic school the aspect of environmental awareness is incorporated too. The architects from both schools who proved to be capable of designing so-called ‘eco-architecture’ could become true opinion leaders and role models and be a source of inspiration for architects who have not taken environmental awareness seriously yet. However, most architects do not want their work to be associated with green terminology such as ‘eco-architecture’ or ‘sustainable architecture’. They would rather use language like ‘smart architecture’ or ‘vital architecture’. Their key thrust is ‘integral quality’ rather than ecology. Respecting this source of motivation has shown to be critical for these frontrunners to actively contribute to increasing the ecological awareness of their architect colleagues and be opinion leaders. Dragging them into the ‘green camp’ would have a contrary effect. Keywords: environmental awareness, architects, opinion leaders, integral quality, smart architecture, vital architecture, cultural creatives, styles of architecture.
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1
Introduction
How can opinion leaders increase the ecological awareness of architects? That is the central question of this paper which is focussed on the Dutch situation. Rogers [1] states that opinion leaders are individuals who lead in influencing others’ opinions about innovations. He also states that the behaviour of opinion leaders is important in determining the rate of adoption of an innovation in a system. In the case of the adoption of ecological innovations in architecture the opinion leaders will be architects. Therefore, before we can determine how they can increase the ecological awareness of architects, we must find out which architects can be considered as opinion leaders in this field. Do these architects have specific characteristics? Or do they represent a specific style?
2
Which architects can be opinion leaders in the field of eco-architecture?
2.1 Characteristics For only a very small group of people care for the environment is leading in their decisions. According to Hoijtink [2] between 1 and 4% of the Dutch people belong to this group. A much bigger group is formed by the so called cultural creatives. Cultural creatives are members of a subculture described for the first time by Ray [3]. This group of people longs for better health, lower consumption and more spirituality and has more respect for the earth and the diversity of life than other people. According to Ray almost 25% of the Americans is part of this growing group. Research of MarketResponse [4] shows that in the Netherlands this percentage is 15% and the number is growing too. It can be assumed that these percentages are similar for architects. This assumption is based on the fact that the group of architects for which care for the environment is leading in their work is also very small. Roughly estimated on my experiences this group of sonamed eco-architects represents between 1 and 3% of the architects. The percentage of cultural creatives amongst architects may be larger than 15% because architects are known to be more creative than most people and being creative is also one of the characteristics of cultural creatives. According to Rogers [1] opinion leaders reflect the norm of the social system. For that reason eco-architects cannot perform as opinion leaders for social creatives and other groups among architects. Based on my personal impression and the above the conclusion can be drawn that of the group of opinion leaders in Dutch architecture the ones interested in ecological innovations are quite often cultural creatives. So the forecast of Ray and MarketResponse, about the growth of the group of cultural creatives, is promising for the adoption of ecological innovations.
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2.2 Styles of architecture The Netherlands has a good reputation abroad as a country of architecture. Many people admire the architecture of famous Dutch architects such as Rem Koolhaas, MVRDV, Neutelings Riedijk and Meijer and Van Schooten. The views held by this generation of conceptual oriented architects have led to numerous typical constructional innovations, such as overhangs of ten metres and folding floors. Alongside this conceptual oriented style another style, the pragmatic style, is typical for the Dutch situation and also very renowned. The economic recession has had repercussions on the architecture business. While architects in the Netherlands already have fewer final responsibilities than their counterparts abroad, most of them cannot allow their views to dominate their work. Clients have become more important now and in many cases this has led to a more pragmatic approach imbedded in an overall strive for high quality [5]. Paul de Ruiter and Hubert-Jan Henket are two internationally celebrated architects representing this pragmatic style. Are opinion leaders in the field of eco-architecture only found within one of these two specific styles? After studying different renowned projects with integrated environmental innovations the answer to this question has to be: no. As can be seen in the different examples, described hereunder, there have been famous architects with a conceptual oriented style and architects with a more pragmatic approach that have been integrating environmental innovations in their work. 2.2.1 Minnaert Building, Utrecht, Neutelings Riedijk Architects The Minnaert building houses facilities for Utrecht University’s geophysics department. Half of the central hall is taken by a shallow pond. The pool plays a key part in the building’s ingenious environmental control strategy. The constant accumulation of heat from computers, lights and occupants means that the building does not need heating, only the removal of heat. This is achieved by collecting rainwater and pumping it through a system of pipes into spaces that require cooling, such as laboratories. Heated water is discharged back onto the roof, where it cools, drips back into a collection vessel and the cycle is repeated [7].
Figure 1:
Minnaert Building [6].
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38 Eco-Architecture: Harmonisation between Architecture and Nature 2.2.2 Posbank, Rheden, Bjarne Mastenbroek The tea-pavilion Posbank is designed by architect Bjarne Mastenbroek and located in the national park Velume Zoom near Rheden. Nature inspired the architect. The façades are as transparent as possible. The construction is made of beams and almost invisible bars of steel while the grass roof is part of the route through the building. The insulation is made of sheep wool and the toilets are flushed with rainwater.
Figure 2:
Posbank [8].
2.2.3 ING-head office, Amsterdam, Meyer en van Schooten architects The building is located on the city’s southern outskirts, near the A10 motorway. Key features of the building include transparency, innovation and a deep-seated respect for the environment. The transparency of the outer wall hides a second layer of glass permitting natural ventilation: not only does this protect against noise from the motorway, but it allows windows to be opened without affecting the temperature inside the building. Climate control takes advantage of the cool temperature of the ground under the building, through procedures aimed at reducing operating costs and preferring naturally cooled ventilating air. In winter the outer façade becomes a true solar panel, preserving heat within the space between the walls so that it will flow into the building when the windows are opened, while the inner façade protects against the sun’s rays [10].
Figure 3:
ING-head office [9].
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2.2.4 Governmental office Ceramique, Maastricht, Hubert-Jan Henket architects The separate blocks that make up the building are separated from each other by four glass solar chimneys that give the building its unique appearance. Combined with specially designed ceiling plenums, they provide natural ventilation in the offices. Outside air is extracted via self-regulating louvres above the windows, and enters the rooms under a specially designed ceiling element. As the sun heats the glass chimneybreast, air is extracted upwards and out. The office floors have a flexible layout. The atrium is part of the natural ventilation system [12].
Figure 4:
Governmental office Ceramique [11].
2.2.5 GWL-terrain, Amsterdam, diverse architects An environmentally friendly and car-free residential area has been realized on the former site of the municipal drinking-water company (GWL) in Amsterdam. Well-known Dutch architects as Meyer and Van Schooten, Kees Christiaansen, Liesbeth v.d. Pol, Willem-Jan Neutelings and DKV demonstrated how care for the environment could be integrated in high architectural quality. Topics were energy and water efficiency, material- and waste reduction, nature and reuse of the existing buildings.
Figure 5:
GWL-terrain [13].
2.2.6 Villa Deys, Rhenen, Paul de Ruiter The clients wanted a practical villa in which they could live until it was impossible to live independently. They had a special wish to integrate the living program with nature. Letting the roof and side façades be clothed with plants, it looks like the three volumes were pushed out of the landscape. The lamella WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
40 Eco-Architecture: Harmonisation between Architecture and Nature façade modules are no simple barn façades but high-tech sunscreens. The water of the swimming pool is connected to a low temperature heating system, which, combined with a heating pump, makes the system energy saving. The roof of the swimming pool is fitted with sky-lights which in combination with the reflecting quality of water makes sure that in the middle of the building a lot of daylight comes in [15].
Figure 6:
Villa Deys [14].
2.3 Conclusion The central question in this chapter is: Which architects may be opinion leaders in the field of eco-architecture? It can be concluded that the answer is not simply found in the architectural style of their work. Their personal characteristics are of more importance. Members of the subculture cultural creatives are more likely to become opinion leaders in this field than others. Their characteristics are a longing for better health, lower consumption and more spirituality. They also have more respect for the earth and the diversity of life than most people. Architects who have given care for the environment priority in their work, so called eco-architects, also have these characteristics but they represent only a small group of architects. For that reason it’s not likely that they will be an influential source of inspiration for a large group of architects who have not taken environmental awareness seriously yet.
3
How can opinion leaders increase the ecological awareness of architects?
Because of the fact that care for the environment is not the main factor in their work, most well-known architects who have integrated environmental innovations in their projects, do not want their work to be associated with green terminology such as ‘eco-architecture’ or ‘sustainable building’. For them care for the environment is only one of the aspects leading to the overall goal of quality, together with comfort, aesthetics and cost-effectiveness for example. Fear for being dragged into the ‘green camp’ explains the fact that in public presentations the eco-aspect of their work is often neglected. As a result their WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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work is not as effective in increasing the ecological awareness of architects as it could be. To surmount this impasse the Royal Institute for Dutch architects (BNA) devised a new strategy and a new name for sustainable building or eco-architecture; vital architecture [16]. Similarly the Foundation for Smart Architecture presented a new approach; smart architecture [17]. Both strategies try to tackle the same problem. Will an analysis of their approaches lead to an answer on the main question of this paper? 3.1 Vital architecture Vital architecture is a strategy intended to inject new élan into thinking about sustainable building, with recommendations on how to make this possible. Care for the environment is regarded as an inherent architectural quality. The recommendations call on architects, clients, consultants and government to change the building process, to change design and to change the climate in which buildings are produced. In the context of vital architecture, the architecture must not only be environmentally sound, but resilient, dynamic and flexible in its relation between form, function and construction, at all scales and through time. Three slogans underline this aim: Space in Time: The essence of sustainable building is thinking ahead Meaning: - Use the present building instead of building a new one - Use a building temporarily - Use a temporary building - Give the building a user manual Time in Space: The sustainably built environment adapts cleverly Meaning: - Ensure flexibility - Make buildings oversized - Make demountability possible at system and component level - Promote prefabrication Time and Space: Sustainable building – an interdisciplinary task Meaning: - Design using integrated methods - Stimulate innovation - Learn systematically According to the BNA the compartmentalized legislation for sustainable building takes insufficient account of other regulations and policy. The resulting contradictions are frustrating so a new élan is required on the part of government. The existing regulations should be reconsidered. Regarding a new élan among architects the BNA states that architects must develop a more acute feel for sustainability. They are presently good at estimating the structural and physical properties of their designs, and this skill gives them the insight they need to overstep conventional limits. In vital architecture architects must similarly develop a sensitivity towards sustainability. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
42 Eco-Architecture: Harmonisation between Architecture and Nature A vital design is more than the sum of its parts; it challenges the architect to selectively integrate and compose all the elements while respecting the constraints of a sustainable context. Starting right from their first design assignments, student architects must strive to cultivate this extra dimension, in which the design and the eventual built product transcends the function for which it is intended. Architects must discover the stimulus inherent in the integration of sustainability into architecture and urban planning. They must rise to the challenge of seeking new concepts that not only work well now, but are valid for the future because they are flexible, dynamic and resilient. In their statement the BNA does not refer to the inspiring role of opinion leaders and their possibilities to stimulate this kind of architecture. But it’s certain that architects will sooner discover the stimulus inherent in the integration of sustainability if architects they admire show the inspiration they get out of solving environmental problems. Designing vital architecture and propagating the inspiring challenge that goes with it can be an effective way for opinion leaders to increase the ecological awareness of architects. 3.2 Smart architecture The Foundation for Smart Architecture declares smart architecture as a reaction against the pessimism that has marked ‘traditional’ ecological architecture ever since its emergence in the 1960’s. It states: ‘The traditional ecological architecture grew out of a doom-scenario of global disaster as a defensive, conservative architecture with a deep distrust of technological innovation.’ Smart architecture is the opposite; an architecture that despite all the major problems brought by human dealings with the environment is still optimistic. Smart is always good and never pessimistic. Smart is airy and graceful and as a concept it is broader than just sustainability or ecology. Smart architecture is an architecture that takes up the ‘green challenge’ as the basis for innovation. Smart architecture is environmentally aware, not just in terms of protecting the environment but because energy and material efficiency is always smart. Smart architecture is also interactive; a smart building presents itself as an interface between its users and the surroundings. It mediates between the demands and desires of users and environment. Smart architecture is efficient, it does more with less. Smart architecture is always time based, it reacts in differing time cycles to changing user exigencies, climatological conditions, changes of function and social development. Smart architecture is ‘natural’, it speaks for itself, learns from nature, uses it when necessary. Smart architecture sees technology not as an enemy of nature but as a natural ally. Underneath the vision of the Foundation of Smart Architecture lies the supposition that environmental issues will radically change architecture. Recent research [18] shows that taking up the ‘green challenge’ as the basis for innovation is a good way to increase the ecological awareness of architects. In that respect the work of the Foundation of Smart Architecture is very promising. Furthermore, the basis for the work of the Foundation of Smart Architecture is promoting the role of opinion leaders by describing inspiring projects and thoughts. The website and book of the foundation are filled with WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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many ideas, projects and concepts, all intended as eye-openers and as sources of inspiration. 3.3 Conclusions Two new strategies try to overcome the impasse in eco-architecture in the Netherlands and to increase the ecological awareness of architects. Both want to improve the image by avoiding worn-out terminology as eco and sustainable and trying to bring in new élan. The lack of ecological awareness and enthusiasm for eco-architecture among architects has a lot to do with compartmentalized frustrating legislation for sustainable building and the pessimism that marked ‘traditional’ ecological architecture. Opinion leaders cannot change the legislation (a task for the government) but they can introduce an optimistic approach. By declaring care for the environment as an inherent architectural quality and taking the ‘green challenge’ as basis for innovation in their projects, opinion leaders can stimulate other architects to integrate sustainability into architecture. ‘Be smart’ should be the message instead of ‘be green’. And being smart is: thinking ahead, building an environment that adapts cleverly and working interdisciplinary. The keyword is quality, not ecology.
4
Conclusions/summary
How can opinion leaders increase the ecological awareness of architects? That was the central question of this paper which is focussed on the Dutch situation. But before we could determine how they can increase the ecological awareness of architects, we had to find out which architects can be considered as opinion leaders in this field. Do these architects have specific characteristics? Or do they represent a specific style? It is concluded that the answer on the second question is not simply found in the architectural style of the work of opinion leaders who integrated environmental innovations in their work. Their personal characteristics are of more importance. Members of the subculture cultural creatives are more likely to become opinion leaders in this field than others. Their characteristics are a longing for better health, lower consumption and more spirituality. They also have more respect for the earth and the diversity of life than most people. Architects who have care for the environment given priority in their work, so called eco-architects, also have these characteristics but they represent only a small group of architects. For that reason it’s not likely that they will be an influential source of inspiration for a large group of architects who have not taken environmental awareness seriously yet. How can opinion leaders increase the ecological awareness of architects? The lack of ecological awareness and enthusiasm for eco-architecture among architects has a lot to do with compartmentalized frustrating legislation for sustainable building and the pessimism that marked ‘traditional’ ecological architecture. Opinion leaders cannot change the legislation (a task for the government) but they can introduce an optimistic approach. By declaring care for WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
44 Eco-Architecture: Harmonisation between Architecture and Nature the environment as an inherent architectural quality, avoiding worn-out terminology as eco and sustainable and taking the ‘green challenge’ as basis for innovation in their projects, opinion leaders can stimulate other architects to integrate sustainability into architecture. ‘Be smart’ should be the message instead of ‘be green’. And being smart is: thinking ahead, building an environment that adapts cleverly and working interdisciplinary. The keyword is quality, not ecology.
References [1]
Rogers, Everett M., Diffusion of innovations, The Free Press, pp. 27, 28, 281, 1995 [2] author of Van geitenwollen sokken naar design jeans, over duurzaamheid en marketing, Kluwer, Amsterdam, 2004, interview by telephone, februari 8th, 2006 [3] Ray, Paul H. PhD, Sherry R. Anderson, The cultural creatives, How 50 million people are changing the world, Free River Press, 2000 [4] Marketresponse, www.marketresponse.nl [5] Hal, A. van, Creativity and technology in the Netherlands, architecture, NOST network, ministry of Economic Affaires, 2005 [6] Credits figure 1: Anke van Hal, Maartensdijk [7] Cleef, C. van, Earth Science-Utrecht University Minnaert Building, the Architectural Review, March 1999 [8] Credits figure 2: G.J. den Boon, Arnhem [9] Credits figure 3: Joost Brouwers, Rotterdam [10] http://www.floornature.com/worldaround/articolo.php/art78/3/en [11] Credits figure 4: Climatic Design Consult, Nijmegen [12] Hubert-Jan Henket architects, www.henket.nl [13] Credits figure 5: Joost Brouwers, Rotterdam [14] Credits figure 7: Anke van Hal, Maartensdijk [15] www.dutcharchitects.com [16] BNA, www.bna.nl [17] Hinte, Ed van, Marc Neele, Jacques Vink, Piet Vollaard, Smart architecture, 010-publishers, Rotterdam 2003, www.smartarchitecture.org. [18] Hal, A. van, Praktische Prikkels, Aanbevelingen ter vergroting van de rentabiliteit van duurzaam bouwen, SenterNovem, januari 2006
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In-between architecture and landscape, from theory to practice B. Ott Department of Architecture, State University of New York at Buffalo, USA
Abstract As both a theoretical and a practical construct, the domain that is neither architecture nor landscape, but of both, is a fertile ground for reflection. The theoretical is addressed by referencing an article by Rosalind Krauss which graphically relates sculpture, architecture and the landscape, including the domains in which they merge. However, the focus here is on the practical: in practice. The last forty years has seen an ideological shift born in the nascent environmental movement of the 1960s. The urge to connect a building to its context, to the landscape, to nature, has become common as we explore new technologies and materials, and mindfully engage siting options in order to produce more sustainable buildings. Presented and elaborated upon are three strategies, with examples, by which to approach this impulse: the metaphysical (by means of the analogy and metaphor), the spatial (as both relational and referential), and the physical, which includes all things material and technological. I conclude with a project in my practice which is driven by the idea that a building can sit in-between architecture and landscape. Keywords: architecture and landscape, environmental architecture, buildings and nature.
1
Theoretically speaking
As a theoretical construct, the domain that is neither architecture nor landscape, but of both, is a fertile ground for reflection. From Rosalind Krauss’ articles of the mid-1970s to Virgil’s dictum that all architecture is an act of violence, we have pondered the encounter of the built with its physical context. Every act of intervention we make into the world is an interruption, an intrusion, in Virgil’s WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060051
46 Eco-Architecture: Harmonisation between Architecture and Nature sense, not an act of beneficence. Small wonder this relationship of opposites is difficult to reconcile, except through a simple dialectic. To elaborate on a particular work of Krauss: in her article, “Sculpture in the Expanded Field,” Krauss pursues a “strategy for reducing anything foreign in either time or space, to what we already know and are” [1] by conjuring a theoretical framework for a set of relations between sculpture, architecture and landscape. She employs an evolving geometric form in which sculpture, architecture and landscape are related, in part by their negatives. In the ultimate version, the inherent complexities in these relationships are filled out with sculpture opposed to site construction, not-architecture to both landscape and architecture, and not-landscape to both architecture and landscape. Her diagram, fig. 1, reveals other relationships which, altogether, wrap the essential dichotomy in a compelling abstract unity.
2
Practically speaking
It is always difficult to translate theory into practice, nowhere more so than when trying to bridge the dichotomy between architecture and landscape. As a practical construct, a building, along with the teaspoon, is the epitome of the designed artifact: the antithesis of nature. Every bit of a building’s construction is about control, about human ordering systems, systems to which the natural world and its behaviors are totally indifferent. In current practice, the desire to connect an artifact with its opposite is a relatively new obsession, spurred by an ideological shift that was born in the nascent environmental movement of the 1960s. At this point in time, rare are the projects subscribing to the modernist canon and its relative disregard for context and environmentally sensitive orientation and material use. One of the primary tenants of the modern movement was to employ the landscape – or any context for that matter – as background to the artifact of desire. The last thirty-five years has seen a gradual erasing of that canon, replacing it with the themes of this conference.
Figure 1:
Krauss’ diagram.
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The urge to connect a building, in some way, to the ecology in which it exists has met with all manner of strategies, from the metaphysical to the spatial to the physical. Following is a brief elaboration of these strategies, concluding with a project in my practice which engages two of the strategies. 2.1 The metaphysical In the metaphysical realm, the analogue and the metaphor have been in use since the rising sun was equated with a new beginning and a mountain top construed as access to the celestial theater. Analogically, the recent project by Foreign Office Architects for the International Passenger Terminal located on the river’s edge in Yokohama, Japan is analogous to a wave; while is not a wave, it is like a wave, made of ten low-slung flowing ramps which at once enfold the outside and weave over and under the main passenger ship terminal, fig. 2.
Figure 2: Yokohama Terminal.
Figure 3:
Growth House.
The building as metaphor – in which something actually acts as something else – to me is both more interesting, and more difficult to accomplish, than the increasingly literal and plastic analogous forms used to represent aspects of the non-built environment. Charles Simmonds’ Growth House, a 1975 project installed at Art Park in upstate New York, is a kitchen garden. Circular walls constructed out of carefully sequenced burlap bags of seeds begin to sprout in the rainy spring. First the crocuses emerge, then the spinach, herbs, peppers, and tomatoes; on to fruit, squashes and so forth as the growing season ends and the walls have literally been eaten by visitors to the park [2], fig. 3. Also metaphoric is my selected entry to the ChiChi Earthquake Memorial competition of 2003. The site is a park in the midst of the region just south of Taipei, Taiwan, hardest hit by the earthquake of 1998. My team proposed the construction of a fault crack dug into the earth as a memorial path through the park. Its interior walls, left rough in excavation, are reinforced with foundations, and anchored into the earthen walls with a steel space frame; an open metal mesh
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48 Eco-Architecture: Harmonisation between Architecture and Nature is all that separates the visitor from the perpetrator; the design is a formal and material reenactment of the event itself, figs. 4.
Figure 4:
ChiChi Earthquake Memorial.
Figure 5:
Choate House.
2.2 The spatial: relations and references Of the strategies which attempt to connect buildings to aspects of nature, the relational and referential are primarily context driven and spatial. Buildings embedded into grade, stepping down a hillside, or perched on a rock outcrop are formally defined by their direct, formal relation to the lay of the land. By example is Roland Choate’s mid-1970s Monticito house located in the dry coastal foothills of Southern California, fig. 5. This project replaces a house destroyed in a wildfire. In its stead, Choate designed a structure all but impervious to fire: it is submerged into the hillside, with exposed and carefully detailed concrete retaining walls and floor; the uphill fragments of the building are minimal and the furnishings present the barest of fire loads. Down the hillside, directly in front of the glass enclosing wall, a swimming pool is plumbed to be a fire fighting reservoir. The building is a fire-deflecting instrument; the form and materiality of the house is generated by the form and materiality of the fire. There is a direct relationship between house and fire. Similar to buildings that relate directly to the land are those which refer to the forms and forces of nature; buildings which define themselves not in terms of WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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these forms or forces, but as a reference to them. In early eighteenth century India, Maharaja Sawai Jai Singh, a student of astronomy, concluded that at that time, astronomy was limited to analysis through mathematical calculations and couldn’t adequately observe the cosmos. After consulting authorities on astronomy, especially those using direct observation, Singh set out to construct two masonry observatories, one in the heart of Delhi in 1724 and the other in Jaipur in 1728, fig. 6. These large scale architectural versions of astronomical instruments are a particularly literal reference to the celestial theater. With intent to improve the accuracy of celestial observations, these poetic constructions measure the rotation of the sun; its movement is magnified as its shadow sweeps across articulated hemispherical cavities. In addition, the positions of the stars are seen in precise alignment from points within its deep bowl [3].
Figure 6:
Figure 7:
Solar Observatory at Jaipur.
Solar Ovens at Odello.
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50 Eco-Architecture: Harmonisation between Architecture and Nature The Delhi and Jaipur observatories are indexes; they point to, refer to, celestial dynamics. In a similar vein is another structure to mention which not only refers to the sun, but uses it (an early form of a passive solar design). One of a few such structures located in the French Pyrenees is the solar oven near Odelló, fig. 7. This elegant and ingenious structure, by means of a mindfully placed field of reflecting mirrors, reflects and focuses the sun’s energy ... in order to bake bread! 2.3 The physical The strategy I have labeled physical includes both the material and technological, and usually refers to sustainability in one way or another. By clever material and formal choices or by simply employing the laws of physics, we can heat, cool, moderate temperatures; create a breeze or buffer the wind. We can use the dispersal of cached water as a resource or an aesthetic; likewise, the sod roof, the heat sink, and the overhang. Examples abound as this strategy is gradually enfolded into the common sense that underlies the practical act of design. One such project rises to the surface: the Academy Mount Cenis built on a former mine site at the center of the town of Sodingen in Germany’s Rhur Valley, figs. 8, 9. The concept for this project is extraordinary in its simplicity. A glass shell, outfitted with louvers, p.v. cells patterned for optimal heat capture and shading, a loose stone floor as heat sink, and a system of water catchment and reuse, create a year-round interior environment similar to Marseilles, on the French Riviera, some 10˚ latitude south of the mine site. Inside, the educational and public offices are housed in bar buildings which face each other to create a warm weather street, complete with an ‘outdoor’ café. This building produces much more energy than it consumes; it distributes the remainder to the town [4].
Figures 8, 9:
Mt. Cenis Academy.
2.4 The project I would like to elaborate on these strategies to link architecture with landscape with a project I am working on for a small ceramic studio, currently under construction in Ithaca, New York. The design of this building focused on two of WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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these strategic realms: the relational and the physical. The primary design strategy was to slide the building into the land in such a way as to render the building an element in the landscape from the entry side and as an artifact from the other, making every possible decision in relation to the site’s physical location and orientation, its specific topography, aspects of the celestial theater, the available vista, and the color of the land. Design priorities for the studio were to orient to a west-facing view over the lake and to provide year-round passive heat control with no moving air to disperse ceramic dust. These conditions resist each other: a western view, over a lake, requires both solar and glare control. By rooting the studio 4’ into grade with a bracketing set of 13” concrete block retaining and cavity walls, we accomplish two things: the future patio is framed by what nominally appears to be a garden wall, and below grade construction serves as a natural insulator and heat sink. The west view wall is spanned in low-e glass and protected with exterior solar shades. With a relatively low-slung ceiling and radiant floor heat for the winter, and ventilation through operable windows and doors instead of ceiling fans in the summer, moving air is kept to a minimum. As well, the interior was to be hosed down on occasion. To ensure hoseability, there are no finishes inside this building other than sheets of exterior grade plywood on frame walls. The sloped-to-drain, coil-heated slab has a brushed finish for traction and is colored 40% grey for heat absorption, the interior face of the block walls are polished, and the exposed wood roof decking oiled. To reuse water runoff, roof gutters sloped to scuppers at three locations distribute water into the landscape. In terms of solar energy recapturing, future solar panels or cells would be outfitted onto the south facing roof. The roof actually bears 7˚ to the west of south; with a roof slope of 21˚, at 42˚ N. Latitude, the setup is almost optimal in regards to the sun and its potential.
Figures 10, 11, 12:
Ceramic studio.
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Conclusion
By paying attention to the vast sets of possibilities which allow the human arts of design and building to garner significance from the natural world, theory and practice take on new meaning. Ecologically engaging architecture is practical, can be poetic, and provides endless opportunities to dance around in Krauss’ diagram.
References [1] Krauss, R., Sculpture in the expanded field. The Anti- Aesthetic: Essays on Postmodern Culture, ed. H. Foster, Bay Press: Port Townsend, WA, pp 31-42, 1985. [2] Lippard, L., Overlay: Contemporary Art and the Art of Prehistory, Pantheon Books: New York, 1983. [3] Perlus, B., Jantar Mantar. Parabola, XV, 1, pp. 65-73, 1990. [4] Stadt Herne, Entwicklungsgesellschaft Mont-Cenis, Druckerei Frisch GmbH: Herne, Germany, 1998.
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Ecological, modular and affordable housing J. Quale University of Virginia School of Architecture, USA
Abstract Modular and panelized construction techniques have the potential of significantly reducing environmental impact – although much of that potential is unrealized among prefab homebuilders in the United States today. The ecoMOD project at the University of Virginia School of Architecture is intended to create a series of ecological, modular and affordable house prototypes. The goal is to demonstrate the environmental potential of prefabrication, and to challenge the modular and manufactured housing industry in the U.S. to explore this potential. In the context of this research and design/build project, an interdisciplinary group of architecture, engineering, landscape architecture, business, environmental science, planning and economics students are participating in the design, construction and evaluation phases of the project. The project is imbedded in the curriculum of the university. Working with non-profit affordable housing organizations, the built homes will be sold to low-income families with subsidies for down payments and financing. The first completed house is currently being evaluated as part of a process to determine the environmental impact of the homes during their life cycle; perceptions of the homes by the owners and neighbors; the energy efficiency of the design and equipment; the feasibility of their transfer to the modular housing industry; the life cycle costs; and the financial viability of taking the prototypes into production. The results of the evaluations will influence later designs, and the evaluation methods and recommendations will be made publicly available. The project is mostly funded, and will continue through to 2010 at a minimum. Keywords: prefabricated construction, modular housing, panelized construction, environmental impact, affordable housing, student design / build, post occupancy evaluation, life cycle assessment, energy efficient buildings, structural insulated panels.
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1
Introduction
Centralized within a climate-controlled facility, prefabricated residential construction offers material and transportation efficiencies, as well as opportunities for stricter quality control. Although several U.S. companies have developed EnergyStar-rated models (a program organized by the U.S. Environmental Protection Agency to encourage energy efficiency), and some sell quality homes superior to conventional stick-built construction, few are seriously looking at the environmental impact of their methods or materials. From a design viewpoint, despite the popularity of modern prefab homes in Dwell Magazine and other mainstream media outlets, very few manufacturers offer quality contemporary design. The vast majority offer standardized designs with open interiors, and exterior skins composed of elements borrowed from late 19th and early 20th century home styles. Among the most surprising trends in prefab housing is the growth in the upper end of the market. Whereas the public perception is that prefabricated homes are an inferior product and only appropriate for the least affluent, increasingly upscale builders are recognizing the financial and logistical advantages of centralized fabrication [1]. Although they seldom emphasize the prefab nature of the construction, major U.S. homebuilders such as the Pulte and Toll Brothers are transitioning from site built to pre-built for their middle and upper-middle market rate houses [2]. Pejoratively referred to as “MacMansions,” the percentage of these that are fully prefabricated homes is still small. Yet major homebuilders clearly recognize the future is in prefab, which can typically offer a more predictable product, with more control over quality, schedule and price. Pulte recently built a panelized prefab plant in Northern Virginia, called “Pulte Home Science” (PHS) where they fabricate structural insulated wall panels, roof trusses and precast foundation systems. They are able to ‘dry-in’ a home is a fraction of the time it takes them to build one on site, and their PHS homes now account for roughly 20% of their single family home market [3]. Yet the benefits of these investments are not trickling down to the lower end of the market. Manufactured housing, the technical term for transportable trailers built to the U.S. Department of Housing and Urban Development (HUD) building code, is still the least expensive way of getting into the new housing market. While the HUD code has gotten more restrictive in recent years – with tighter guidelines for insulation and the attachment of the trailers to foundations – the fact remains that manufactured houses are still inferior products. They are difficult to finance, built with the cheapest possible materials, and like an automobile, tend to depreciate in value. In contrast with HUD code homes, prefabricated homes that use modular, panelized or component prefab elements are built to code of the local jurisdiction. While this requires manufacturers to devise creative ways to track the correct code requirements for a given home going down their assembly line, many states and municipalities in the U.S. have recently or are about to adopt the International Residential Code. Unlike HUD code houses, these homes are considered WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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permanent construction, and do not face financing problems, and therefore tend to appreciate in value in the same way as a site built house. The general public is not sophisticated enough to recognize the difference between manufactured homes and better quality modular or panelized prefab homes. So its not surprising the Pulte doesn’t market their prefab homes any differently than their stick built. In fact, Pulte is literally replicating the same models in their PHS facility that they build on site. It is likely that most of the owners of those models don’t know about the prefab nature of the construction. The availability of affordable housing in the U.S. is a growing problem. As construction costs increase and home values continue to grow, the challenge of buying a home in many markets is becoming insurmountable for many. House values have increased 20% in just the last two years, while incomes for middle and lower class Americans have remained flat [4]. A family that chooses to buy a manufactured house is typically restricted to placing that house on a suburban site, where land is cheaper. In addition, manufactured houses are designed for the width and orientation of suburban lots, fig. 1. No major manufactured home company offers models designed for urban lots with the entry side facing the street. In addition, the typical single-wide module for these homes measures 12’-0” to 14’-0” wide by 48’-0” long – a size nearly impossible to transport into most tight urban areas. By default, families in the affordable housing market are being pushed to the periphery, where they have to take on the added financial burden of driving everywhere.
Figure 1:
2
Standard modular house in urban setting; note entrance on right.
Figure 2:
Entry deck of ecoMOD1 house under construction.
Goals of project
It is in this context that the ecoMOD project was developed. ecoMOD is a collaborative research and design / build project at the University of Virginia School of Architecture focused on creating well designed and well-built homes that cost less to live in, minimize damage to the environment, and appreciate in value. The goal of ecoMOD is to create a series of proto-typical ecological and modular houses for low-income families in central Virginia. Over the next WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
56 Eco-Architecture: Harmonisation between Architecture and Nature several years, UVA architecture, engineering, landscape architecture, business, environmental science, planning and economics students and faculty will provide a minimum of four prefabricated houses. Through partnerships with Piedmont Housing Alliance (PHA) of Charlottesville, Virginia and Habitat for Humanity of Greater Charlottesville (HFHGC), the homes will be placed in established communities. PHA will sell three of the homes to low-income families in the Piedmont region with down payment and financing assistance. The first PHA house, called the OUTin house, fig. 2, was designed, prefabricated off-site, and sited in the Fifeville neighborhood of Charlottesville on 7 1/2 Street. It is being sold as a two-unit condominium (basement unit sold separately from the upper two floors), and includes a rainwater collection system that delivers potable water, an extremely energy efficient construction system, a solar hot water collector, and landscape of native, drought tolerant plants. ecoMOD2 – known as the preHAB house – is a panelized design that will house a family displaced by Hurricane Katrina. Constructed in partnership with HFHGC and the HFH affiliate in Jackson County, Mississippi, the design is intended to demonstrate the potential of prefab for Habitat affiliates. HFH is already pursuing panelized construction with their “Operation Home Delivery” project focused on delivering wall panels from around the country to be set up in the hurricane devastated Gulf Coast region. The goal with the preHAB house is to take this one step further, by designing a home that can be pre-fabricated in various ways – panels, room-sized modules, and/or smaller components. Typically, HFH affiliates use conventional wood framing or ‘stick-built’ strategies with a large, often inexperienced volunteer work force. The future homeowners are usually required to put some ‘sweat equity’ into their home, and while they purchase the home, the price is significantly lower than the cost of the home. With ecoMOD2, we imagine future disaster relief efforts where HFH affiliates from around the U.S. could use their volunteers to build house panels or modules or components without taking too much time or money away from their own local building efforts. The perception among Habitat officials is that prefab construction conflicts with HFH’s volunteer labor strategies. These officials see the value in the dramatic scene of a crowd of volunteers hammering conventional walls together to energize the community and maximize fundraising opportunities. Yet with a carefully designed prefab house system, HFH affiliates from across the country could also contribute to a larger effort. By offering choices for the scale of their involvement, the preHAB house strategy could include smaller affiliates without the resources to ship a complete home to a disaster area. The shipping distance is another factor to consider with prefabricated components. In the context of Hurricane Katrina, HFH affiliates in the states adjoining Mississippi and Louisiana could contribute modules. HFH affiliates within 500 miles could produce wall and roof panels, and others could ship smaller and simpler components. This idea can be likened to the way thousands of Americans prepared first-aid dressings in their homes for injured soldiers during World War I. With more than 200,000 homes destroyed by hurricanes in 2005, the Gulf Coast is in the early stages of a long rebuilding effort. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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This first preHAB house will be sited on an empty lot in a 1960’s affordable housing subdivision in the city of Gautier, Mississippi. Design will begin in Fall 2006 on ecoMOD3 for a low-income family in the Charlottesville area. Partnering again with PHA, two project options are being considered. One possibility is to rehabilitate and add a modular unit to a tiny historic home, believed to have been built in the 1880’s by a freed slave in Charlottesville. The modest house is in a serious state of disrepair, and was slated for demolition. Historic preservation students would participate in the design phase, along with architecture, engineering and landscape architecture students. The other option is to produce a small multi-unit elderly housing complex. In this scenario, the shell of the units – the modules – would be prefabricated by a modular manufacturer, with the students providing the design, and building the smaller scale modules and components. Each completed house is to be monitored and evaluated carefully, with the results guiding the designs of subsequent houses. The evaluation process occurs in two overlapping courses with additional participation from students and faculty from non-design disciplines such as business, environmental science, economics and planning.
3
Design phase
The design process for the ecoMOD homes is structured to maximize the educational possibilities of the project. The project is imbedded in the curriculum of the University, and the coursework has been recognized by professional organizations and major media outlets for its’ innovative pedagogy [5]. A series of mixed graduate and undergraduate design studios in the School of Architecture, combined with independent study and thesis students from the University’s School of Engineering and Applied Science, form the core of the design process. The two-year cycle includes an academic year for design, followed by a summer of construction, and an academic year of evaluation. The studios are collaborative and interdisciplinary, and they include architecture, landscape architecture, and potentially historic preservation students. The engineers meet regularly with the rest of the team, but also have their own coursework. The first design studio for ecoMOD1 began with student presentations on relevant prefab and ecological case studies, and design studies that address specific activities within the home. The team collaborated in small groups, and the groups were regularly shuffled in order to minimize the potential of isolated subgroups. Landscape architecture students worked along side architecture students, and were often participating in the same assignments. The University of Virginia architecture and landscape architecture programs were combined into a single department in 2004, and a significant percentage of graduate students participate in dual degree programs between two of the four disciplines in the school – architecture, landscape architecture, urban and environmental planning, and architectural history. Participants in the first studio were paired with planning students for an analysis project on the neighborhood for the first house – Fifeville, a WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
58 Eco-Architecture: Harmonisation between Architecture and Nature traditionally African-American neighborhood. A neighborhood development workshop taught by a planning professor offered the context for this collaboration. Although the students welcomed the possibility of interdisciplinary work, the results of analysis did not live up to the faculty’s expectations. Analysis of urban context takes on very different forms in the two disciplines, and the students found it difficult to collaborate within their interdisciplinary sub-groups. The students probably required a clearer introduction into the values supporting their discipline’s distinct worldviews, to create a more open-minded environment. The Project Director will do the assignment again, but with more clearly defined introductions. However, one of the most positive aspects of the early collaboration with the planning students was the ensuing discussion about the broader agenda for the project. Planning students were asked to frame a set of guidelines for decisionmaking during the design process. Most participants were surprised that the lists prepared by the planning students overlapped with the collaborative list developed by the architecture and landscape architecture students. However, one planning student subgroup posited that the design ought to replicate the existing architectural language of the neighborhood. A heated discussion on this topic helped all parties better understand and articulate their positions. It also led to a self-imposed commitment by the designers to present their design ideas to members of the Fifeville Neighborhood Association (FNA). Intended as a way to receive feedback about their preliminary design ideas, the meetings with FNA became an essential part of the design process. The students thought some of their design ideas might not align with the opinions of the FNA membership, but they found they were not so far apart. The participants in the feedback sessions (four sessions over a period of six months) never questioned the contemporary nature of the designs, and mostly responded to functional issues. The most heated discussion in the FNA meetings related to the appropriate location for the kitchen – nearest the street or nearest the backyard. Eventually the designers found an effective middle ground, with the kitchen in the middle and a clear line of sight to both the street and the backyard. The students also interacted regularly with professional members of the local community – from building department officials to local contractors and consultants. A team of student managers working with the faculty Project Director collectively made important design decisions. Decisions that required a comparison of multiple possibilities were often documented with a six pointed decision web – a concept adapted from the professional world. The web required the team to remember that decisions are a careful balancing of aesthetic, technical, financial, social and ecological issues – with the sixth point being an overall score. In concept, the webs were meant to facilitate the decision process, but in reality, the webs more mostly treated as a documentation of a decision. The students were not enthusiastic about the decision webs at the time, but now appreciate the graphic representations of their collective thinking. During the break between the two design studios, the client decided to change the site, forcing the team to respond to a complex challenge. The students set about redesigning the house for the new narrower lot. The change WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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significantly delayed the development of the design, but forced the team to address the adaptability of the design to various sites. The challenge was repeated again two weeks before the end of the spring semester, as the team was headed into the construction phase. A series of events led to another site change – still in the Fifeville neighborhood – but a site with a different solar orientation, topography and urban context. Once again, the design had to change, and the schedule was delayed. As with the first site change, the design team responded by exploring the ways the design could be more easily sited on various topographies, and in various microclimates.
4
Build phase
The start of the construction process for ecoMOD1 was delayed by nearly two months. The students fabricated eight small modules for the two-story house in a decommissioned airport hangar owned by the university, and transported them to the infill site, fig. 3. Unlike conventional modular houses, the students designed their modules to fit the proportion of urban infill sites, and to be easily transported along narrow streets. The modules were less than half the size of a typical module, allowing for the use of a less expensive crane, and the possibility of moving the modules to the narrowest streets with the tightest turning radiuses. The majority of the design studio students elected to stay in town after their graduation, and participate in the construction process, fig. 4. Most of them had little or no building experience. The team worked through all the logistics themselves, including coordination between various building trades, material procurement, and transportation. They also built the entire of the house, with the exception of the basement / foundation, and the final installation of the plumbing, electrical and mechanical infrastructure. Students worked with professionals for each of these scopes of work, but could not be held responsible for the permitting process.
Figure 3:
Second of eight modules lowered on basement / foundation.
Figure 4:
Construction team preparing insulated roof joist.
Visits to a few modular house fabrication facilities confirmed that the required tool and equipment where within our budget. The funding for the tools, WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
60 Eco-Architecture: Harmonisation between Architecture and Nature and a significant percentage of the summer student fellowship money was provided by a local non-profit funding organization. The remainder of the funding was raised the Project Director via grants and donations. The students devised strategies to work around the more sophisticated equipment that was beyond our reach financially. For example, one company uses pneumatic devices to allow the modules to ‘hover’ as they move along the assembly line. The students built the eight modules in a single line in the hangar, and only moved them when it was time to transport them at the end. For this, they designed and fabricated a set of ‘house skates’ using left over framing material on wheels to roll the modules over a trailer, where they were lowered on to the bed. Conventional jacks were used to lift the house, and three or four people easily pushed the modules while on the “skates.”
5
Evaluation phase
Each completed house is to be monitored and evaluated carefully, with the results guiding the designs of subsequent houses. The evaluation process occurs in two overlapping courses with participation from students and faculty from architecture, engineering, commerce, business, environmental science, landscape architecture and planning. As of this writing, the evaluation is appropriately 50% complete, with a more thorough analysis available in late spring 2006. The ecoMOD1 evaluation team of students is looking carefully at the choices made by the design / build team. This includes the following: 1) monitoring the energy efficiency and water use of the house, contrasting the data with simulations and comparable homes 2) thorough life-cycle assessments of the materials and construction process 3) a post-occupancy evaluation with the eventual homeowners, including questions about thermal and lighting comfort, as well as evaluation of the design hypotheses set out in the design phase 4) an affordability analysis comparing the cost of both the prototype and the eventual production model to other available modular homes 5) a cost/benefit analysis and investigation of the design’s suitability for production with a major manufacturer, and 6) a summing up of the key recommendations, including a prioritized list of issues for the next design / build team to consider. Preliminary conclusions indicate the following: 1) while the potable rainwater collection system will save the homeowners money and reduce the home’s environmental impact, the cost of the filtration equipment negates the efficacy of recommending it for city locations where the municipal water supply is relatively inexpensive 2) stricter guidelines need to be established to make sure the emphasis on building material efficiency at the hangar during the off-site construction process is not lost during the final phase on site, where a dumpster was available 3) while the design adequately addresses shading from the summer sun, it does not appear to sufficiently address the potential positive contribution of solar heat gain during the winter months 4) the material life cycle assessments so far support the design decisions, but additional research is required into a comparison of the cementitious lap siding (as selected for ecoMOD1) versus the more conventional choice of vinyl siding; as well as corrugated galvalume WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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roofing versus a membrane or asphalt shingle roof 5) the centralized air handler and ductwork – located in the middle of the conditioned space appears to contribute to the energy efficiency of the mechanical system 6) the combined effect of the energy efficient wall and roof system (structural insulated panels), the equipment and the passive design strategies seem to indicate a minimum of a 40% reduction in energy costs for the homeowners and 7) the preliminary financial analysis indicates that if the ecoMOD project were a for-profit business venture, it would be able to successfully find its niche in the largely unserved market for ecological, prefabricated and affordable housing. One other significant consideration is PHA’s policy to always sell homes at their appraised value, as a part of their commitment to build wealth in the community. This means they need to raise funds to subsidize the down payments and financing on the homes, to make them available to families between 40 and 80% of the area median income (PHA’s target market). HFH and other organizations tend to ignore the appraised value, and sell the home for as little as they can bear. This policy contributes to the growing recognition at PHA that single-family affordable homes are no longer a viable option in the Charlottesville area. With house prices and construction costs skyrocketing in the last four years, PHA is increasingly looking to single-family home renovation, and multi-family complexes. The ecoMOD1 house appraised $40,000 higher than comparable homes built by PHA, despite the fact that the costs per square foot were the same or lower than these homes. Therefore measures need to be established to minimize the appraised value of the house – at least at the time of the initial appraisal. The appraiser indicated that a significant percentage of that additional appraised value was related to the generous exterior decks. The architectural and financial evaluation will be complete in May of 2006, and the building monitoring and performance evaluation will be complete one year after the homeowner(s) moves into the space(s).
6
Conclusions
The copyright registration process has begun for the design of ecoMOD1, including four adaptations to various solar orientations and topographies. At a minimum, the design drawings for ecoMOD1 and ecoMOD2 will be available for purchase by the summer 2006. The designs will be marketed to affordable housing organizations throughout the mid-Atlantic region, and the ecoMOD team will soon thereafter begin the process of speaking with modular builders about taking some of the designs into production. The most significant impact of this project has yet to be evaluated – specifically the degree to which this form of reality-based service learning contributes positively to the professional lives of the students. The results of that evaluation will reveal themselves over the course of many years. As of this writing, one former student is on her way to Sri Lanka to participate in the postTsunami rebuilding effort as a United Nations employee, and another is designing affordable housing for a large corporate architecture firm. For further information, the ecoMOD website is www.ecomod.virginia.edu. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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References [1] [2] [3]
[4] [5]
Traynor, T., AB Exclusive State of the Industry Report for 2005: Total Housing Up 7% to 2.88 Million Units. Automated Builder, pp. 8-9, January 2006. Kelley, S. P., personal communication, April 2005, Project Engineer, Pulte Home Science. Holtzman, J., Assembly Required: Builders push the productivity envelope with greater attention to sub-assembly techniques. Big Builder Magazine, November 2004, www.bigbuilderonline.com/Industry-news; and similar figures from personal communication in reference [2] above. Paycheck to Paycheck: Wages and the Cost of Housing in America; study published by the National Housing Conference, August 2005, www.nhc.org/chp/p2p/. Taylor, E., AIA Recognizes Ecoliteracy in Architecture Schools, Environmental Building News, July 2005; Global Challenges, CNN International, segment on ecoMOD broadcast several times in November and December 2005; Cox, S., Design, Build, and Repeat, Architectural Record, page 54, November, 2005.
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Flexi-Living: adaptable property, adaptable housing, transforming lives I. MacBurnie Department of Architectural Science, Ryerson University, Canada
Abstract Founded on the interrelated principles of flexibility and choice, Flexi-Living presents an innovative approach towards more affordable and sustainable residential design and development. It is a middle ground solution combining the best of urban and suburban design and development, adapted to an industrialized building process featuring prefabrication, green architecture, and the latest technology in concrete, steel, and glass. Flexi-Living comprises a pioneering environment in which change is embraced rather than eschewed, in which mass production is celebrated rather than masked, and in which homeowners are empowered rather than forced to comply with a set of rigid and unalterable norms and standards. It proposes a range of property types, from small lot to large lot, from narrow and deep to wide and shallow. It envisages both neighbourhoods which are transformable rather than fixed for all time, and districts in which a plot of land may be subdivided and sold for profit. It features a range of housing types, from single-family detached homes to loft-like walk-up condominium apartments. It proposes dwellings that are adaptable rather than inflexible, such that, according to a homeowner’s particular desires, a house may be expanded or reduced in size. Flexi-Living is intended for Greenfield sites situated on the edge of major North American cities. However, it is equally applicable to Greyfield and Brownfield redevelopment. Keywords: housing, affordability, sustainability, flexibility, choice, live-work, property, change, empowerment, urbanism.
1
Contemporary (sub)urbanism
The three suburban communities sharing the Levittown moniker may never have been esteemed by the architectural, landscape, or planning avant-garde, but they WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060071
64 Eco-Architecture: Harmonisation between Architecture and Nature proved to be both enormously popular with middle class consumers, and highly influential for subdivision developers. Premised on the mass production and consumption of inexpensive starter homes (exemplified by the slab-on-grade, one and one-half storey bungalow that could be easily expanded horizontally or vertically), the Levittown concept manifested a certain logic in the land-use segregated, baby-boom era that it came to personify. Within a few decades, however, the rapidly rising cost of land, labour, materials, and infrastructure on the edge of major metropolitan areas, coupled with the emergence of a more diverse and fragmented marketplace, conspired to render this one-size-fits-all approach to subdivision development obsolete. In its place, the suburban real estate industry substituted a range of niche-market products, each geared to a specific class segment and comprising a distinct, physically and socially segregated neighbourhood, highlighted by large, single-family detached homes for the more affluent, smaller, “zero-lot line” houses (meaning that the house is set-back from the property line on three sides, while straddling the property line on the fourth) for those somewhat less well off, and townhomes, condominiums, and walk-up apartments for the rest. While on the one hand the contemporary marketplace offers consumers a wider choice of housing, on the other hand it ties consumers’ hands. In the contemporary marketplace, the individual dwelling has in the main become inflexible, prevented from changing either because of zoning (houses invariably occupy the maximum coverage), or because of private restrictions originated by the developer and included in the property deed. This is especially the case in the United States, where the tract-house approach to subdivision development on the edge of major metropolitan areas was, long ago, usurped by the Planned Unit or Common Interest development. In these communities, a once public territory is replaced by a private, at somewhat higher density, one that is distinguished by a comprehensive set of restrictive covenants and highlighted by collective amenities, such as a golf course, an environment in which continuity is valued and change is shunned. In Canada, where in similar locales the single-family house still predominates, the trend has been toward the provision of ever smaller and narrower lots. In the absence of rear lanes, where vehicles can be stored, the front lawn and tree-lined street that are imbedded in the image of suburbia have given way to a concrete and asphalt landscape dominated by automobiles, driveways, and garage doors. For at least several decades, these environments have been lightning rods for a multitude of critics, especially those who decry sprawl. In the vanguard of the assault and in the propagation of alternative models of development has been the New Urbanism.
2 New urbanism Cornell, Ontario represents the latest wave in suburban residential design and development in Canada. Located in the Greater Toronto Area (GTA) suburb of Markham, the project was master-planned by the Florida-based architectural and planning practice headed by Andres Duany and Elizabeth Plater-Zyberk, according to principles of the New Urbanism. The development features a streetWIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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and-lane pattern of road infrastructure (the Levittown model dispensed with the lane), a “town centre,” several parks, and several thousand dwelling units, for the most part consisting of single-family, detached houses. Conceived for the midrange segment of the middle class marketplace, the residential density achieved in Cornell is perhaps fifty percent higher than in conventional, detached-home subdivisions in the GTA. The typical width of a Cornell lot is somewhat narrower than in a conventional neighbourhood. Most dwellings employ a zero-lot line configuration, and setbacks are significantly reduced. The vast majority of dwellings are single-family detached, two- and three-stories in height. Individual properties feature the house and a detached garage, which is situated to the rear of the lot and accessed directly from the back lane. With all garages located to the rear, Cornell features a streetscape free of driveways. A small number of apartments are provided in the development, the bulk located above stores in the mixed-use buildings that comprise the subdivision’s centre, with the occasional apartment built above garages situated on the subdivision’s alleys. Cornell asserts that its design goes a long way towards achieving affordability and sustainability. In the main, these are said to be advanced by the “compact” master plan, resulting in increased residential density and decreased infrastructure per capita, by the embrace of a broader and more diverse population, reflected in the provision of a range of housing types, and by the provision of live-work opportunities. Though the argument is seductive, it is, unfortunately, specious. Consider the matter of affordability. While in the shorter term a smaller lot may be less expensive to purchase in a high land-cost area like the GTA (although the experience of other New Urbanism projects suggests otherwise, as New Urbanism generally results in higher property values, sometimes much higher, than conventional development), in the longer term affordability is contingent on other factors, such as the ability to adapt to changing circumstances. For instance, what happens to the notion of affordability when a homeowner is elderly and living on a fixed income, when he or she becomes unemployed, or when interest rates begin to rise? Affordability in part means the ability to capitalize on an investment, and a lot and house are a homeowner’s greatest assets. While a lot and house can be sold in Cornell, lots and houses cannot be capitalized. Why is that the case? Because Cornell lot types and dwelling types, like those of conventional subdivision development, are inflexible, fixed for all time, as if time stood still. Affordability would be enhanced by a homeowner being able to capitalize on their asset through the sale of part of their real property: their land, house, or both. Unlike pre-Levittown subdivision development throughout North America, to which New Urbanism designers are said to have given more than a passing glance, Cornell lots cannot be subdivided and sold. And, unlike the manner by which urbanism unfolded in older neighbourhoods throughout North America, to which New Urbanism designers are said to have paid particular attention, Cornell houses cannot be converted to duplexes or other types of accommodation. In Cornell, only a handful of dwellings have apartment accommodation located above their WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
66 Eco-Architecture: Harmonisation between Architecture and Nature garages, and there are no separately-accessed basement apartments, as is the case throughout the GTA. McGill University researchers have demonstrated that, after land, the most expensive aspect of housing is finishes. Cornell, however, does not offer homeowners the choice between a fully outfitted interior and a shell to be completed through sweat-equity, over time. No effort has been made to reduce the cost of finishes, in part because finishes is one of the most profitable aspects of housing development. Consider the matter of sustainability. Like so many New Urbanism projects, Cornell occupies a distant Greenfield site whose eco-system was shattered; lacking was a remediation strategy. Cornell advertises itself as a live-work community, but this is achieved by sleight of hand: the work part of the equation is accommodated in a widened hallway or converted bedroom. For most, however, the reality is that they still must commute elsewhere to work, not to mention to shop. Like so many New Urbanism projects, Cornell employs a hierarchical, street-and-lane pattern of road infrastructure, the street component comprising an aesthetic space, the lane component a functional space. As most activities are auto-oriented, the car-clogged rear lane is Cornell’s principal civic space, providing back-door entry to the home. Largely a symbolic space, the street is effectively a little-used stage-set. Like so many New Urbanism projects, Cornell housing does not employ energy-saving technologies such as green roofs, photovoltaic cells, bio-filtration systems, or pre-fabricated, recycled, and non-toxic building materials. Accordingly, energy consumption and emissions are about the same as elsewhere. Like so many New Urbanism projects, Cornell offers an exceptionally limited range (two) of housing types: there are no starter homes and no single-floor homes for the elderly; the vast majority of apartments are clustered in a single complex that comprises the town centre. Cornell dwellings can neither be expanded nor reduced in size: residents are expected to move into a different type of accommodation when circumstances warrant. And, like so many New Urbanism projects, Cornell cannot be intensified over time, unlike the manner by which urbanism has unfolded throughout history in older, inner-city neighbourhoods in North America. At the end of the day, Cornell, like so many New Urbanism projects, is a cleverly packaged real estate development that accomplishes little in terms of affordability or sustainability. It may be the best the marketplace offers, but it leaves much to be desired.
3
Flexible urbanism
Outlined below in black, the Mixed-Density Pocket is the cornerstone of a more affordable and sustainable suburban development paradigm known as the Metropolitan Purlieu. Elaborated by this author for Canada Mortgage and Housing Corporation’s Centre for Future Studies, the Purlieu was conceived through a collaborative, workshop process (involving architects, planners, academics, suburban real estate developers, municipal officials, housing experts, and representatives from homeowner associations) both as an alternative to the low density, land-use segregated model of residential development which WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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predominates on the periphery, and as an alternative to the New Urbanism. The Purlieu comprised a compact, transit-oriented, “green” community of considerably higher density in which mixed-density pockets – consisting of a range of adaptable lot and housing types – were enveloped by rings of increasingly dense and mixed-use structures culminating in mid-rise perimeterblock and point-block towers fronting major thoroughfares. Programmatically, the Purlieu encompassed rather than rejected all categories of development currently located on the periphery – from light industry to Big Box stores – re-conceptualizing and re-formulating these in the process.
Figure 1:
4
The Metropolitan Purlieu.
Flexi-Living
The mixed-density pocket is unique in that it alone, among alternative development models for suburbia, embraces change rather than rejects it. Change is the very essence of human existence, yet in the environment where most will live, change is precluded, whether that be in a conventional development, or one designed according to the principles of the New Urbanism. Suburban development models are so commodified that they are conceived for an ideal condition rather than a human condition. Consider a commonplace example. In most conventional and New Urbanism developments, a homeowner not only is unable to alter his or her home’s appearance by enlarging a window, but is unable to change even the colour of the front door. Consider a more significant example. Residential lots and housing types are so limited in type and restrictive in scope that not only is it unfeasible to expand a dwelling – for instance, to accommodate a larger kitchen or house a member of an extended family – but there is no room for amenities such as a backyard swimming pool, one of the very icons of the Good Life. In most conventional and New Urbanism projects, individual desires have been subordinated to both a notion of the common good, as advanced either by a homeowners’ association or a real estate developer. As one’s lifecycle unfolds, it becomes necessary to relocate from one dwelling, neighbourhood, and subdivision to another, and then again, until one retires on a fixed income and then goes through the process yet again.
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Figure 2:
The Flexi–Living formula.
The mixed-density pocket was conceived and formulated to embrace change. It comprises an environment in which change has been built-in from the outset, and imbedded in the zoning and private property deeds, a circumstance that neatly sidesteps one of the many impediments to change in the built environment, that of NIMBYism. The pocket is a place where one can live, work, and grow old and retire, without ever having to move. Moreover, it is a place where one’s property and home is a manifestation of one’s desires and stage in life rather than a representation of the highly edited and packaged vision WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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of a real estate brochure. Flexi-Living in the mixed-density pocket responds to the ambitions of real individuals living in the real world. As revealed in the following images, it is a middle ground solution combining the best of urban and suburban design and development, adapted to an industrialized building process featuring prefabrication, green architecture, and the latest technology in concrete, steel, and glass. It comprises a pioneering environment in which mass production is celebrated rather than masked, and in which homeowners are empowered rather than forced to comply with a set of rigid and unalterable norms and standards. Flexi-Living proposes a range of property types, from small lot to large lot, from narrow and deep to wide and shallow. It envisages both neighbourhoods which are transformable rather than fixed for all time, and districts in which a plot of land may be subdivided and sold for profit. It features a range of housing types, from single-family detached homes to loft-like walk-up condominium apartments. It proposes dwellings that are adaptable rather than inflexible, such that, according to a homeowner’s particular desires, a house may be expanded or reduced in size.
5
C-Type: the convertible house
This 250 square meter, loft-like, live-work, detached dwelling situated on a wide and shallow lot accommodates a dedicated office and separately-accessed, above-ground, in-house apartment. Lot and house have the built-in potential of subdivision: the lot can be readily severed and the dwelling easily modified to generate a free-hold semi-detached, an ideal proposition for the empty-nester. One semi-detached unit is designed to readily accommodate living on one floor, ideal for the elderly.
Figure 3.
6
N-Type: the narrow house
This 250 square meter, loft-like, live-work, zero-lot line, detached dwelling situated on a narrow and deep lot accommodates a dedicated office and WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
70 Eco-Architecture: Harmonisation between Architecture and Nature separately-accessed apartment located above the garage. Lot and house front onto two streets, facilitating access, the accommodation of amenities such as a swimming pool, and the division of home and apartment.
Figure 4.
7
L-Type: the starter – elderly house
This 125 square meter, loft-like, live-work, zero-lot line, semi-detached dwelling situated on a narrow and shallow lot accommodates a small, two-story starter house that can be easily modified to accommodate living on one floor. It is ideal for the elderly.
Figure 5.
8
E-Type: the expandable house
This 200 square meter, loft-like, live-work, zero-lot line, detached dwelling situated on a wide and shallow lot can be expanded to accommodate a dedicated office and separately accessed, above-ground, in-house apartment.
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Figure 6.
9
A–Type: the apartment house
These 150 square meter, loft-like, live-work, separately accessed, walk-up apartments situated above a ground-oriented parking structure accommodate a dedicated office. Each is a two- or three-story dwelling featuring double-height living spaces and balconies and large terraces oriented for views and maximum privacy.
Figure 7.
10 Conclusion The Flexi-Living concept as outlined above is being further articulated and refined in collaboration with federal and provincial housing officials, urban planners, engineers, homebuilders, and subdivision developers. This winter, the concept formed the basis of this author’s entry in Archetype, a sustainable housing and urbanism competition sponsored by Toronto’s Design Exchange. The submission featured Flexi-Living’s concern for managing residential intensification and growth over time. Similar to Flexi-Living, it featured a variety of adaptable house types (referred to as wide, narrow, and tall), two of WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
72 Eco-Architecture: Harmonisation between Architecture and Nature which comprised zero-lot line, detached dwellings, and it emphasized the notion of lot severance. The competition is currently being judged, and the awardwinning schemes will be announced in late April. The scheme awarded first prize will be built as a demonstration project at Kortright, an ecological interpretation center located a few miles north of Toronto.
Figure 8.
References [1] [2] [3] [4]
Friedman, A., Planning the New Suburbia: Flexibility by Design, UBC Press: Vancouver, 2002. Canadian Housing and Mortgage Corporation., Flex Housing: Homes that Adapt to Life’s Changes, C.M.H.C., Canada, 1999. Friedman, A., The Adaptable House, McGraw-Hill Professional Publishing: New York, 2002. Friedman, A., The Grow Home, McGill-Queen’s University Press: Montreal, 2001.
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The study of restoring an eco-habitat of the traditional Paiwan tribe in Taiwan C.-J. Chen Graduate Institute of Urban Development and Architecture, National University of Kaohsiung, Taiwan, the Republic of China
Abstract Paiwan is the third largest aboriginal tribe in Taiwan. The most particular, original habitat of Paiwan people is their housing system; all structures are constructed with numerous slats of stone and are built at the same altitude on mountains, merging with landscape. This type of vernacular architecture represents strongly, affordable resources and a kind of natural attitude that responds well with the environmental conditions. Using the local materials, applying the natural cooling and the landscape adaptation, and forming a selfsufficient community, the Paiwan habitat behaves as an eco-habitat and reflects the subtropical characteristic of Southern Taiwan. Unfortunately, most of the traditional Paiwan territories are decomposed or abandoned due to political reason as well as the changing society during vicissitudinary periods in Taiwan. The government has urged the people to recover or restore the surviving villages. This study’s purpose is to discuss how to find an appropriate approach for restoring the Old Chi-Jia village, one of the most complete and intact traditional Paiwan villages in Taiwan. Different topics such as the investigation process, the architectural intervention and community conservation are discussed to establish an optimal strategy for restoring the Old Chi-Chia village. Keywords: aboriginal tribe, restoration, Paiwan, eco-habitation, Old Chi-Chia.
1
Introduction and history
The evidence found for prehistoric human habitation in Taiwan dates back 12,000 to 15,000 years. Different theories indicated that Taiwan’s aborigines came from two places: southern China and Austronesia. Recent research shows WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060081
74 Eco-Architecture: Harmonisation between Architecture and Nature that Taiwan could be the starting point of the Austronesian emigration route (Bellwood), i.e. Taiwan’s aborigine people are an important branch of Austronesian. The Austronesians in Taiwan include two main groups: the plains aborigines and the mountain aborigines. The plains aborigines (called Pinpu tribe) resided mainly in the plain and coastal regions of Taiwan. Han people (Chinese) since the Dutch period came and have assimilated the plains aborigines in 1624. Until now, the plains aborigines could not be obviously identified. Taiwan’s aborigines are considered the northernmost Austronesian people. Among them, the official classification divides them into 12 major mountain tribes and 10 Pingpu groups. Mountain aborigines use the “tribe” as their settlement unit. Those in the north (Atayal and Saisiat) live in scattered villages, those in central and southern Taiwan (Paiwan, Ami, Tsou) in compact communities, and the settlements for Bunun and Lanyu-based island (Yami) have the combination of the above features. Their houses are usually made of bamboo-wood columns covered with thatch. The Paiwan, Rukai and Bunun roof their buildings with stone slate and wood and often build their homes slightly underground. The Paiwan, closely related in material culture to the Rukai, are divided into the Raval and Vutsaul peoples. The Vutsul can be further subdivided into the Paumaumaq, Chaobobol, Parilarilao, and Pagarogaro groups. The tribe of Old Chi-Jia belongs to Paumaumaq.
2
Concept of original habitation
2.1 Site environment The original settlement of the Paiwan tribe was usually situated on the contour of mountains. The altitude of settlement was around 500 to 1000 meters, where the relative mild climate provided both rich hunting resources as well as fertile soil. The houses of village were built close to linearly along the contour; all openings were in the same orientation. Every house unit had its independent territory: space, granary and courtyard, forming a self-sufficient habitat system. The traditional houses of the Paiwan and Rukai are similar to those of the Bunun. A site was levelled by digging into a slope, and then an earth and stone terrace that extended outward to provide a slightly lower than ground level floor and a slightly higher courtyard was revealed. Houses of the southern and eastern Paiwan, however, were frequently constructed at ground level. The Old Chi-Jia village orients in a southwest direction, with the mountain background in a northeast direction that brings in the air stream from the Taiwan Strait into the village in summer and deters the cold current in winter (see Figures 1 and 2). All houses are built on the terraced field of contour. The pilled stone slates are around the two sides and the backside of the house, which protect and indicate every living unit. Some “Chief Houses” have a pilled stone platform in front of courtyard as a symbol of importance, which protects against wind. All grounds (inside and outside) are manually consolidated or covered with stone WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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slates. In this manner, the house disturbs minimally the ground and thus performs a high permeability (see Figure 3).
Figure 1:
View of Old Chi-Jia village.
Wind direction
Site map of Old Chi-Jia village (2005). Rain water
Plateform resists the wind
Water flow
Water flow
Figure 3:
Figure 2:
A profile of traditional houses of northern Paiwan tribe.
2.2 Housing system The most particular feature of north Paiwan houses is its use of stone slate, which abounds in the mountains of southern Taiwan. Figure 4 describes a typical Rukai house in Pington County, and Figure 5 shows a typical Paiwan “Chief House” in Pington county. People use stone slate to build houses that are cool in the summer, warm in the winter and robust enough to resist typhoons. In other words, a structure entirely suited to the climate of southern Taiwan. Many traditional houses, which were erected more than one century ago, remain intact in southern Taiwan. Figure 6 is a traditional Northern Paiwan house that survived. Besides, the Paiwan and Rukai are famous for their outstanding wood and stone sculpture. Ancestral figures were often carved in shallow relief into house posts, slates, or plank panels. Figure 7 shows carving on wood planks.
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76 Eco-Architecture: Harmonisation between Architecture and Nature
Figure 4:
Typical Rukai House in Pington County (referred from original figures of Chijiiwa Suketarou).
Figure 5:
A typical Paiwan “Chief House” in Pington county (referred from original figures of Chijiiwa Suketarou).
Figure 6: Side view of typical Paiwan Figure 7: Carved planks on front walls. House. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Menaces and challenges of the Paiwan tribe
Although the government encourage various affirmative actions to assure the aboriginal peoples in Taiwan, the menaces and challenges are still inevitable. They are assumed as follows: (1) Disadvantaged social position (2) Inappropriate housing quality (3) Vanishing traditional settlement The Paiwan people as other minorities usually compete vigorously in most domains when they try to merge into a “normal” society. Despite limited agricultural products, the local people still mainly depend on the housing benefit and different income supports from government. The offered modern housing system seems to satisfy only the minimum requirements for living, all inherent respects and indigenous contents cannot be recognized. Moreover, the living quality, such as natural comfort and environmental atmosphere, is also incomparable to the traditional ones. Consequently, the young people leave their native land to chase or to accept “new values”; the traditional culture and the traditional settlement can hardly be inherited and are under danger of decomposition.
4
Important criteria of renovation
According to previous observations, this renovation project will face some critical situations. Two important objects are considered: (1) the preservation of living culture and (2) the possibility of renewable development. Three missions should be defined: (1) Traditional respect in space – typology of house (2) Enhanced living quality – improvement on comfort (3) Preservation of materials and construction techniques Figure 8 shows how the modernized Paiwan houses change the living aspects. When village people try to interpret the modernity and to become more “civilized”, not only does the totem of the tribe disappear, but also the principal respects, such as social ethic and ancestral. In fact, continuous usage of the homes by future generations should be the most important philosophy when restoring these houses. And the correct reuse of houses could empower the new developments (eco-tourism, open-air cultural museum, etc.) for the tribe. The authentication of the house should consist of both the appearance and traditional materials and construction techniques. Figure 9 shows the comparison of hand cut and machined stone slates. The quality of stone slate as well as traditional constructors is also critical. For this project, local people are urged to participate in the construction for two reasons. The first is to offer more working possibilities to the tribe; the second is to train and to pass on their traditional techniques in an informal
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78 Eco-Architecture: Harmonisation between Architecture and Nature manner to those are willing to learn. A community participation action and several workshops will be held before and during the project.
Figure 8:
Modernized Paiwan houses in Old Chi-Jia Village.
Figure 9: Comparison of hand cut (left) and machined (right) stone slates.
Figure 10:
Typical feature of Paiwan House.
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To respect the traditional construction manner, a typical feature of traditional house is defined (see Figure 10). Table 2 shows the main components and its traditional names in Paiwan. Table 1:
5
Original names in Paiwan.
No. 01
Name Courtyard
Paiwan No. Name Paiwan katsasavan 09 back wall tsaiqus tseleb
02 03
Bracing front wall
qeoze tseleb
10 11
roof vali front roof tsaiqaiau qaliu
04
Window
quzong
12
back roof
tsaikuz qaliu
05
plank panel
sasuaian
13
side wall
tsaikiti tseleb
06
Door
paling
14 tabernacle
tavi
07
main post
taukes
15
Mui
08
Granary
sang
stone
Architectural interventions
5.1 Restoration inventory In order to set up a feasible restoration plan, a fundamental inventory was necessary. The inventory list consists of materials to be used in different parts of the house, the damaged description (mentioned quantitatively and qualitatively), the principal plants around the house and the actual circumstance of every house. According to the classification of different damaged levels, the sequence of restoration for houses was defined. Due to limited budget, the project focused on deciding the priority of recovering the houses that could be reused quickly and could be demonstrated as exemplary models for the county. Figure 11 shows an investigation sheet form and inventory list. 5.2 Modified structural system Traditional houses are built with less durable materials except for the stone elements. Especially, the weight of a stone roof can be hardly supported because of the ageing of wood element (beams, rafters). Therefore, the safety of houses decreases gradually. In this project, the integrity structure of a house should be improved and refined, thus not only was the traditional structure reinforced or rebuilt, but also a modified structural system was proposed. Anti-termite treated wood material and more durable stone slates should replace the old ones respectively.
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80 Eco-Architecture: Harmonisation between Architecture and Nature
Figure 11: Table 2:
Investigation sheet form and inventory list.
Indoor Environmental Factors (Data referred from Meng [3]).
Assessment Indoor topics Temperature (°C) Standard values
Winter Summer 20~24
23~26
Winter 20.97 (traditional) Summer (traditional) Winter (modern) Summer (modern)
PMV
24.93 21.13
Win. -1 ~ +1
10%
-0.33
8.42%
0.59 -0.33
29.1
1.28
ACH (l/h)
PPD
Q (m3/h/m2)
Sum.
Win. Sum. Win.
15%
3~6
3~6
8.36
7.59 21.91
8
Sum. 8 19.9
12.84% 13.09 5.44 34.31 14.26 8.41%
5.91
1.05 6.08
0.55
39.61% 14.17 2.52 14.57
1.32
5.3 Improved ventilation Due to ethnic policy and natural disasters (mudflow, flood and earthquake), several migrations occurred prior to the actual habitation. Most of the people live WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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in the modernized but inappropriate housing system. To discuss the comfort of Paiwan houses seems a little extravagant. Very few researches mentioned the physical states of such housing system. Meng [3] studied how the natural ventilation influences the indoor environment of the Northern Paiwan Tribe. The indoor Predicted Mean Vote (PMV), Predicted of Percentage Dissatisfied (PPD), Air change per hour (ACH) and Air exchanged rate (Q) are discussed. The measured results show that the traditional Paiwan houses perform better on ACH and Q, which provide a superior indoor air quality compared to the modern ones. For PMV and PPD, the traditional ones also have the advantage of thermal comfort. The comparison results are shown in Table 2. For traditional houses, the smoke from cooking and campfire can barely dissipate due to the inefficient ventilation. The stacked stonewalls and roof can lightly “respire” and can evacuate a small percentage of the smoke. But in modern houses, the stone slates are usually stacked and “sealed” by mortar. It is necessary to propose a modified ventilation system (shown as Figure 12) that can be combined and built with main structural system. The indoor air quality of houses will be thus improved.
Main wooden beam
large roof plank Main wooden beam
Steel section Steel section to conduct the smoke
Figure 12:
Stone slates
Ventilated steel section beneath the main wooden beam.
6 Conclusion and perspective As a unique aboriginal habitation in southern Taiwan, the Old Chi-Jia village should have a chance to be a living heritage of Paiwan culture. The meaning of this restoring project is to preserve the authentic habitation and at the same time, to consider the future perspective of the tribe. Comparing to the modern houses, the advantages of traditional houses on thermal comfort and on IAQ are clarified. Such wisdom and the ecological concept fund in vernacular habitation can always inspire us on how to harmonize the natural environment and resources with human settlement. More aspects like anthropology and environment science should be introduced and integrated into such projects to resolve comprehensively the requirement of aboriginal tribes in Taiwan.
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82 Eco-Architecture: Harmonisation between Architecture and Nature
References [1] [2] [3] [4] [5] [6]
P. Bellwood, J. Fox, and D. Tryon, eds., “Austronesian Prehistory in Southeast Asia: Homeland, Expansion and Transformation” The Austronesians. Pp. 96-111.1997 Chijiiwa Suketarou, The Dwellings of Aborigines in Taiwan (in Japanese), 1960 Tokyo, 1988 Taipei. Hui-Tung Meng, The effects on the Environmental Changes by Natural Ventilation to the stone-plate Houses of Northern Pai-Wan Tribe (in Chinese), Master thesis, Shu-Te University of Technology, 2005. http://www.gio.gov.tw/taiwan-website/5-gp/yearbook/2004 Moderate thermal environments-Determination of the PMV and PPD indicesand specification of the conditions for thermal comfort”, International Standard ISO7730, 1994. Chi-Jen CHEN, Recovery Project for Stone Slate Houses of Old Chi-Jia Village, Technical Report, 2006.
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Urban planning and the quality of life in Putrajaya, Malaysia D. Bt Omar Faculty of Architecture, Planning and Surveying, Universiti Teknologi MARA, Shah Alam , Malaysia
Abstract The overriding principle of urban planning is to provide the best quality of life for every one to live, work and play. The quality of life process offers an opportunity to have more input in the urban planning process. The underlying aim of the Total Planning Doctrine is to develop a community that should be able to meet changes in values within society and be able to contribute to improving the quality of life, especially in a new town development including Putrajaya. This paper is based on research that has explored the social and physical characteristics of Putrajaya in order to measure their relative impacts. A perception survey was carried out to evaluate the level of quality of life experienced by the residents. The analysis sought to uncover information relating to community life in Putrajaya which was specifically planned to provide a good quality of life for its inhabitants continuously until the completion of the development. The findings of this research could be used to address the future development of Putrajaya and also other towns. The findings will be useful in determining the physical planning and quality of life indicators for sustainable development. There is a need especially in Malaysia to have new clearer policies to guide and build sustainable environments. Keywords: urban planning, quality of life, The Total Planning Doctrine, community life, sustainable environments.
1
Introduction
The Total Planning Doctrine is a new approach to the planning and design which is expected to guide the physical planning system focusing on the concept of sustainable development. This is a paradigm shift that should enable physical WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060091
84 Eco-Architecture: Harmonisation between Architecture and Nature and social planning to be integrated with moral and spiritual values that will not separate economic growth from social needs and justice that will contribute towards sustainability and increase the quality of life for society. The Government of Malaysia has attempted to provide a policy to keep pace with the rapid economic growth so as to bring about a better quality of life to the people [1]. In this country, it is still not easy to determine the sustainability of a city as there are no standard criteria or measurement tool for urban sustainability. However, as for the urban sustainability concept is absorbed into The Total Planning and Development Principles. The application of this Doctrine has been included in the development planning of Putrajaya [2]. The trend analysis sought to uncover information related to community life in Putrajaya which specifically planned to provide a good quality of life for their inhabitant continuously until the completion of Putrajaya development. The researcher intended to carry out a research in every three years. This is the second research. The first research was carried out in 2000, the first year of the re-settlement programme of the Federal Government administrative officers [3]. Traditionally, planning was based on physical planning criteria. However, with The Total Planning Doctrine, the future cities and new towns require a new set of planning standards and the final outcomes will be reflected in the design of human settlements. The Doctrine has embedded the underlying premise of attaining sustainable communities. Planning and development need to provide a living environment that is socially beneficial with sufficient and optimum provision of infrastructure, utilities such as clean water supply, amenities such as cleansing, electricity and drainage systems; public facilities, recreational spaces and commercial and industrial centres. The underlying aim of the Doctrine is to develop a community who should be able to meet changes in values within society and be able to contribute to improving the quality of life, especially in new town development. The research is to explore the social and physical characteristics of Putrajaya in order to measure their relative impacts. A perception survey is to evaluate the level of quality of life experience by the residents. The findings of this research could be used to address the future development of Putrajaya and also other towns. Comments from the respondents were very encouraging and it was suggested that the research should continue. This is the first research in urban planning and the findings will be useful in determining the physical planning indicators for sustainable development.
2
Urban planning, sustainable development and the quality of life
The overriding principle of urban planning is to provide the best quality of life for every one to live, work and play. The quality of life process offers an opportunity to have more input in the urban planning process. Consideration of the social factors is pivotal for the success of urban development as a social city and this very much related to the concept of self containment. This can only be achieved by policies that take into account the society’s needs and through the WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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building of balanced new settlements rather than the single-use–unbalanced extensions to existing settlements. There is a need for a broader policy for new town development which focuses on the interests of new large communities and their future [4]. The developers, future residents in the vicinity, local authority, state, national government and the larger public are influenced the character of the future growth throughout the state must be considered. If the new town developments were to provide a framework for better life and environment, the planning objectives and strategies must be truly inspired. There is a need to have new clearer policies to guide and build sustainable environments. Sustainability requires specific initiatives and needs to be coordinated. However, in some cases the environmentally desirable urban forms might be less desirable in economic and social terms. Wing [5], in his research on Hong Kong and Singapore, found that there is much to improve on the overall quality of life, cost of living, infrastructure, urban amenities, recreational facilities as well as culture and arts. Urban life is generated by the movement and living function provided by the urban centres which allow people to go anywhere in safety. Rogerson [6] stated that in the list of the world’s most liveable cities and various quality of life assessments the highest feature from an urban area is security.
3
Background of Putrajaya
Putrajaya, a new administrative capital city for the Malaysian Federal Government was planned as early as 1981. Putrajaya was the first major intelligent garden city developed in Malaysia. The total area is 14,780 hectares where about 30 per cent of the area is for the administrative centre. The physical planning was to ensure that it is a sustainable city providing high quality living to its population. In 1996 the Federal Government set up Putrajaya Corporation to monitor the mega project implementation. Putrajaya Corporation Act 1995 (Act 536) came into effect on January 5, 1996 and listed the power of the Corporation which is to administer and manage the Putrajaya Corporation Area on behalf of the Federal Government. The corporation functions like a local authority to ensure the success of Putrajaya towards 2020 and beyond. When complete, Putrajaya is expected to have 570,000 population where 250,000 will live in the core area and the remaining 320,000 in the surrounding residential areas. Putrajaya masterplan, based on the Garden City Concept, delineates the area into twenty precincts, of which five are in the Core Area included Government, Commercial, Civic, Mixed Development, and Sports and Recreational. The remaining 15 are precincts of various sizes also known as peripheral area. Twelve of the 15 precincts make up the residential neighbourhoods. Each unit was planned for some 3,000 dwellings or 15,000 population with a mix of low, medium and high cost housing and a variety of designs. A total of 67,000 homes of varying ranges, sizes, types and densities have been planned. Each neighborhood is equipped with necessary public facilities and amenities. Among the facilities provided in the residential areas are schools, hospitals, shopping centres, mosques, multipurpose halls, learning centres and parks. This fulfilled WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
86 Eco-Architecture: Harmonisation between Architecture and Nature the underlying principle of the doctrine towards more sustainable communities and a better quality of living environment.
4
Quality of life satisfactions in Putrajaya
This paper presents the data analysis and synthesis from Putrajaya’s residents perception surveys. The results and the major findings pertaining to the quality of life in Putrajaya development are presented. The discussion in this paper focuses on the components of the built environment which contribute to the quality of life as experienced by the residents of Putrajaya. The research sought to uncover information related to community life in Putrajaya which was specifically planned to provide a good quality of life for their residents. The analysis is presented in two parts. Part one is on the general analysis that discusses the background of respondents and the overall perceptions, part two focuses on the quality of life achieved. The quality of life in a particular area was a subjective issue and that each respondent may have different views or perceptions with regard to subject matter [7]. It is of theoretical interest to explore the relationship of the built environment and the satisfaction level of different living areas. Campbell [8] addressed the concept of quality of life as measuring the people’s perceptions, evaluation and satisfaction. Leitmann [9] listed four reasons for assessing the quality of urban life: a. to make comparisons b. to identify problems c. to develop policies d. to monitor and evaluate the implementation of interventions. For many researchers satisfaction was viewed as more definable, more plausible and more appropriate to measure and compare people’s assessments on quality of life experience [10].
5
General analysis
This part is to demonstrate the results of data gathered from Section A of the original survey questionnaire. The data retrieved includes age, race, gender, length of stay, types of houses, employment by occupation, problems faced by respondents and suggestions for improvements. The summary of the results from the respondents to the survey questionnaire is tabulated and discussed below. The analysis was considered important because their perceptions would demonstrate the quality of life there as they experienced living there. The research found that more than 78% of the total respondents were married. The majority of respondents were having a family size of four which are lower than the national standard of five. This is important in relation to the housing design and community facilities standards. It was found that majority of respondents were in the age group of between 20-40 years old. The distribution of respondents by working categories reflected that the distribution of Putrajaya residents and the highest were those in the Clerical and Related Workers WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Category. The data was associated to the provision of the type of accommodation. In terms of duration of stay of the respondents in Putrajaya, it was found that majority were with two years. The highest percentage which was about 30 percent found to have been staying for two years.
6
Residents’ perceptions
In this second part, the analysis is focused on Section B of the original survey questionnaires which retrieved information on respondents’ perceptions. This is concerning the community facilities, infrastructure services, commercial facilities, open space and surrounding areas, feeling safe in the living area and safety of property, feeling about living in the particular new town, sense of neighbourhood community, adequate comfort in housing, mobility and public transportation service. Their perception is assumed to be an important indicator for a particular new town as an ideal or unsatisfactory place to live in. The respondents had freedom to make choices regarding the environment. The residential environment is important in the analysis of the quality of life because of the role it plays in human experience. This part of the research attempts to measure the effect of the environment on the respondents’ life and to compile and compare the quality of life to be achieved in future years. Perceptual evaluation of these indicators were tabled to illustrate quality of life dimensions. The findings from residents’ perceptions may become one of the ways in getting people involved so as to ensure the continued success of their community. The survey questionnaire asked whether the respondents’ perceptions were completely satisfactory, satisfactory, average, unsatisfactory and completely unsatisfactory with regards to the indicators used to quantify the quality of their living environment. Tables 1-9 show the findings of this research. The quality of life would increasingly play a significant role in various planning dimensions and would likely to be a complex one [11]. Table 1: Public Facilities Primary Schools Secondary Schools Smart Schools Religious Schools Higher Learning Institution Place of Worship Entertainment Centre Police Service Fire Service Hospital Clinic
Public facilities. Perceptions of respondents (residents) Completely satisfactory Completely satisfactory Satisfactory Completely unsatisfactory Completely unsatisfactory Completely satisfactory Unsatisfactory Satisfactory Satisfactory Completely satisfactory Completely satisfactory
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88 Eco-Architecture: Harmonisation between Architecture and Nature Table 1 shows five of the public facilities listed were rated as completely satisfactory by the respondents which include primary school, secondary school, place of worship, hospital and clinic. These were the five very important facilities been provided by the government to ensure good living environment for the communities [12]. They were satisfied with the provision of smart school, police service and also fire service. They rated entertainment center as unsatisfactory while both religious school and higher institution as completely unsatisfactory. These three facilities were not available during the time of research. In many cases for place of worship and hospital were rated as completely satisfactory. Based on the findings there is a need to provide more and better facilities for the communities in order to change their perception to reach the completely satisfactory level. As for shopping facilities the majority from respondents were unsatisfied with the provision of lower and higher order commercial services. (Please refer to Table 2). The shopping facilities especially for the lower order goods should be provided as early as the settlement. Majority of them had to go to Kajang, Bangi and other nearby towns for their daily goods. The research found that their living situation were harder after moving into Putrajaya because many of them were used to living in Kuala Lumpur where shopping facilities were abundance and within easy reach. Table 2: Shopping facilities Lower order goods Higher order goods Table 3: Infrastructure Electricity Water supply Telephone
Shopping facilities. Perceptions of respondents Unsatisfactory Unsatisfactory Infrastructure facilities. Perceptions of Respondents Satisfactory Satisfactory Satisfactory
Infrastructure facilities (refer to Table 3), playground/open space facilities as shown in Table 4 and environment (refer to Table 5) were well served in Putrajaya and are at the satisfactory level. Table 4:
Playground and open space facilities.
Open space/playground Children’s playground Public open space Other open spaces Landscaping
Perceptions of Respondents Satisfactory Satisfactory Satisfactory Satisfactory
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Table 5: Environment Safety of self and properties Aesthetics of the surrounding area Cleanliness of the area Landmarks Signage Table 6: Social aspects Social activities Sense of community Feelings about living in Putrajaya
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Environment. Perceptions of respondents Satisfactory Satisfactory Satisfactory Satisfactory Satisfactory Social aspects. Perceptions of respondents Average Average Satisfactory
Table 6 demonstrated that majority of respondents rated their social activities and sense of community to at the average level. This may be due to the length of stay, whereby most of them were new to each other and also lack of social programmes and activities being organized for the community. However, they were satisfied with the feeling about living in Putrajaya.
7
Conclusion
The research was intended to study the quality of life through the perceptions of those working in Putrajaya. They were residents of Putrajaya. The perception study of the quality of life were considered as a significant role in Putrajaya for being the first city development in the country to be guided by the Total Planning Doctrine. The findings showed that there are several planning and implementation issues need to be reviewed in order to achieve the planning goals and objectives which lead towards a better quality of life. It is recommended that more research to be done on how to integrate quality of life dimensions into overall Putrajaya development as well as another new developments. It is hoped that our planners could devise better strategies to enhance the quality of life in the communities.
References [1] [2]
Mahathir B. Mohamad (1998). The Way Forward, London: Weindfeld & Nicolson. Government of Malaysia, (2001). Total Planning and Development Guidelines, Department of Town and Country Planning, Peninsular Malaysia, Kuala Lumpur, (2nd Printing). WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
90 Eco-Architecture: Harmonisation between Architecture and Nature [3] [4]
[5] [6] [7]
[8] [9] [10]
[11] [12]
Dasimah Bt Omar (2004). Quality of Life in Putrajaya: Trend Analysis, Research paper, Institute of Research, Development and Commercialisation, Universiti Teknologi MARA, Shah Alam, Malaysia. Dasimah Bt Omar, (2002) New Town Development in Peninsular Malaysia: Case Studies of New Town Development by State Economic Development Corporations, PhD Thesis (unpublished), Universiti Teknologi MARA, Shah Alam, Malaysia. Wing, H.C., (2000). Planning Policies and Quality of Life in Hong Kong and Singapore, Quality of Life in Cities: 21st Century QOL, The Second International Conference, Singapore, March 2000. Rogerson, R.J., (1999). Quality of Life, Place and Global City, Yuan, Yuen & Low, eds., in Urban Quality of Life, Critical Issues and Options, National University of Singapore. Marans, W.R. and Cooper, M. (2000). Measuring the Quality of Community Life: A Program for Longitudinalman Comparative International Research, Quality of Life in Cities: 21st Century QOL, The Second International Conference, Singapore, March 2000. Campbell, A., Converse, P., & Rodgers, W. (1976). The Quality of American Life, New York: Sage. Leitmann, J. (1999). Can City QOL Indicators be Objective and Relevant? Towards a Tool for Sustaining Urban Development, National University of Singapore. Marans, W.R. and Cooper, M. (2000). Measuring the Quality of Community Life: A Program for Longtudinalmand Comaparative International Research, Quality of Life in Cities: 21st Century QOL, The Second International Conference, Singapore, March 2000. Dissart, J.C. and Deller, S.C. (2000). Quality of Life in the Planning Literature, Journal of Planning Literature (FJPL) Vol. 15, 1 (August). Putrajaya Development Corporation, (2004).Briefing Notes.
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Section 2 Historical and philosophical aspects
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Evaluating the sophistication of vernacular architecture to adjust to the climate E. Tsianaka RMJM London Ltd., Cambridge, UK
Abstract Globalisation in architecture and the highly developed artificial technology of the 1950s allowed architects to design buildings without responding to the needs of the people in their climates. After the oil crisis of the 1970s, architects started referring back to local and traditional methods for inspiration to re-establish the relationship between form and climate. This paper aims to evaluate whether the vernacular architecture was sophisticated enough to offer wise and sustainable solutions to the housing needs. Taking Greek vernacular architecture as a test case, the study is based on the comparison of two architectural types, which were developed at the same time in different climates; the Cycladic type and the North-Hellenic Tower type. The white cubical houses are generally considered more picturesque and photogenic compared with the less well-known NorthHellenic loggia houses. This study shows that both types have many qualities and were developed in response to local and regional characteristics with the Tower type presenting more sophisticated answers. In addition, the paper tries to support the study of not only stylish buildings, but also less elegant and cosmopolitan houses. It is possible that many sophisticated architectural answers are hidden behind the appearance. Keywords: Hellenic vernacular architecture, Cycladic, North-Hellenic Tower, architectural form, loggia, sahnisin, winter and summer zone.
1
Introduction
Vernacular architecture has attracted the imagination of many architects. It is believed that traditional wisdom and lore in buildings may still offer wisely managed, economically effective and culturally appropriate solutions to the world’s housing needs [1]. However, was the vernacular architecture WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060101
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Figure 1: Cycladic house.
Figure 2: North-Hellenic Tower house.
sophisticated enough to establish a dialogue with the environment and furthermore what environmental qualities were developed? This study investigates two types of architecture of the past; the Cycladic type and the North-Hellenic type, as illustrated in figures 1 and 2. An effort to answer the afore-mentioned questions is made by examining the reaction of both types to summer and winter sun; to seasonal temperature variation, and the effect on their architectural forms. In addition, architects’ search of imagination design related closely to the study of popular and elegant buildings, such as the Mediterranean vernacular cubicle houses [2, 3]. This work endeavours to combine the investigation of both popular and less known traditional buildings. The paper consists of five parts. The first two parts analyse the climate as well as the historical and social background of each location. Section four explains their architectural characteristics, while the fifth section examines their reaction to seasonal temperature variations and the effect of sun on their architectural forms, investigating the way people tried to welcome the sun in winter and shun the glare and heat in summer supported by diagrammatic illustration of shading geometry. The last part concludes the investigation.
2
Location and climate
2.1 Cyclades The Cycladic style was developed in the South Aegean area of the Mediterranean Sea. It was mainly centred on the Cyclades, a group of twenty-three islands and most especially in Amorgos, Mykonos and Santorini. The landscape is diverse with mountains, gorges, sheer coasts, plateaus and sandy beaches. The climate is WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Figure 3: Comparison of Ta Air Temperatures in [0C] (MeteoNorm).
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Figure 4: Comparison of Irradiations of Global Radiation horizontal in [kWh/m2] (MeteoNorm).
typically Mediterranean; it is moderate and coastal, with sunny, dry and warm summers and mild and damp winters. There is little diurnal and seasonal temperature variation and freezing temperatures are uncommon, fig. 3. The islands are subject to hot, dry winds blowing from the south and dry, cold winds blowing from the north [1]. The radiation from the sun is intense, especially in summer, fig. 4. 2.2 North Greece The North-Hellenic tower style was developed in the northern Greek mainland, in Makedonia, Thessaly and East Thrace and the North Aegean. The topography has great variation: mountains, valleys and hillsides, but the usual landscape is coastal valleys surrounded by mountains. This area belongs to the continental zone, which has a climate consisting of sunny, dry and hot summers and cold, damp winters. Generally, it is a two-season climate with important diurnal and seasonal temperature variation, fig. 3. There are some local climate anomalies due to the Alps: special winds called bora in Greece [1]. The sun’s radiation is high, especially in the summertime, fig. 4.
3
Historical and social background
3.1 Cyclades The Cycladic type dates from the seventeenth century [4], when this area was a part of the Ottoman Empire. During this period, the islands suffered from continuous pirates’ raids. Therefore the settlements were located inland, so as not be visible from the sea. In spite of the history of successive occupations, after the sixteenth century the majority of the population remained Greek and was Greek Orthodox [2]. The South Aegean culture was heterogeneous, with many influences from ancient Greek, Roman, and Byzantine civilizations. People used to spend more time living outside their houses than inside. They gathered in the central square, in streets, and in churches for daily discussions and social contact. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
96 Eco-Architecture: Harmonisation between Architecture and Nature 3.2 North Greece The North-Hellenic tower type dates from the sixteenth century when Greece was under Ottoman occupation. At that time, the population was mixed. Greek, Jewish and Turkish people lived together in separate ethnic-religious neighbourhoods. Heterogeneous cultures were characteristic of this time with Byzantine and Ottoman influence and many strict local rules especially for the female population. People had to spend more time in their residences, without many opportunities for entertainment and social contact. Women used to socialise in the yards or in the streets in front of their houses.
4 Architecture 4.1 Cycladic architecture The popular Cycladic villages were developed organically in repetitive forms based on cell-like additive tradition. The houses are very close to each other and in many cases the buildings share party walls or roofs. Individual Cycladic buildings are not necessarily unique but collectively form a unique cubical urban environment famous for the inspiration derived from them, as shown in fig. 5. Both interior and exterior spaces are simply and economically developed. The plans, rectangular shapes usually with 1:2 proportions, vary according to specific needs within the limitation of the building order. They are single or two-storey houses and include living space, sleeping rooms and kitchen area. In some cases, working room is comprised while the toilet is always out of the building. Each dwelling has a small outdoor space: an interior courtyard, a yard or a roof terrace. The Cycladic structure is masonry, contrasting with the mild local climatic conditions. Three reasons explain this choice: stone was the main local material, the islands were susceptible to earthquakes and the people preferred more permanent structures [1]. The most visible element in Cycladic architecture is the flat earthen roof (doma) used for drying products, sleeping on hot summer nights, or for social contacts, an element harmonized with the hot dry climate. The whiteness of the Mediterranean village, for both practical and symbolic reasons, is a very interesting architectural feature. The white surfaces make the streets more negotiable after dark, maintain a level of hygiene, protect against diseases, and reflect the summer heat. Moreover, they unify the settlement giving emphasis to the sense of civic pride in the community.
Figure 5: Settlement of Mykonos Island. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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4.2 North-Hellenic architecture The North-Hellenic villages are mountainous and fortified principally because the enemies’ invasions were frequent. The built-up area is typically dense and nucleated with irregular streets and with a central square. The most interesting characteristic was the division of built-up areas into ethnic-religious quarters, allowing the co-existence of these cultures. This less popular type is an evolution of Byzantine architecture, as presented in figure 6 with influences from both Western and Eastern culture [1]. This style, with more complex architectural structures and exhibiting greater skills, was reflected not only in public, but also in residential architecture [5]. They are mainly two-storey houses. The ground floor walls are usually made of local stone 60cm to 65cm thick, while the upper are lightweight walls 20cm to 25cm thick [6]. A very interesting architectural feature is the slightly inclined roof, at thirty degrees inclination, found in temperate climates with a consistently dry summer, as in northern Greece. The most notable elements in North–Hellenic architecture are the hagiati and the sahnisin, both of them controlling the level of sunlight in dwellings. A hagiati (loggia) is a semi-enclosed space, also called doxatos. It is an efficient topological and morphological element not only of the Greek traditional dwelling, but also of the Balkan and Minor Asian dwellings. It is situated either in ground level or in upper levels. Hagiati was a multi-purpose room. Workers used to spend their time after work continuing the process of the agricultural products, women used to weave and to prepare the daily meal in open-air fireplaces. A sahnisin (solaria) is a wood-frame extension of the main room cantilever over the street to the masonry bases. This extension could be either in the front façade of the house or on the sides. Principally, it was designed for the formal room of the home and there were no specific size dimensions. This morphological and functional architectural feature derives from Byzantine vernacular architecture and not from Ottoman architecture, as the Ottoman dwelling adapted sahnisin from Byzantine dwellings and spread it throughout the Balkans [5]. There were also social reasons for the sahnisin, as it worked as an opening to the outside world for the female population. Women hid behind the curtains of sahnisin windows, watching what was happening in the streets when it was dangerous outside. Besides this, the sahnisins were useful for cooling off in the summer days, especially when the house did not have a hagiati.
Figure 6: Evolution of North-Hellenic Tower type.
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5
Effect of climate on architectural form
The gradual evolution of buildings in vernacular architecture is based on the experience of many centuries and depends on the local environment and climate, as well as the social characteristics. The analysis of the climatic response of vernacular buildings is proved to be more complicated than expected. It is difficult to separate out cultural and social issues, and also technical constraints set by availability of materials, topography etc, none of which are strictly climatic. However, climate produces certain effects on architectural forms, which are easily observed [7]. The following section endeavours to identify the environmental qualities of each traditional type and to investigate their reaction to temperature variations, and winter and summer sun. 5.1 Cycladic type: environmental qualities The Cycladic type embodies some environmental qualities, essentially because of the functional simplicity of the structure. On the one hand, the rectangular plan is the perfect shape for hot and dry climates and on the other hand, the space configuration is very helpful, because the multi-purpose room is usually facing the south or east. This type of architecture puts more emphasis on protection from light not only at the scale of individual buildings, but also at the urban scale. The sun’s radiation is very intense, and the need for sun protection is fundamental. Moreover, people preferred to spend more time outside than inside. Consequently, how does vernacular architecture seek to protect people from the rich and dramatic light? First of all, architecture tries to limit light in settlements by a combination of narrow and shade-inducing streets, tunnels and vaults. There are numerous examples of the previous architectural elements in Cyclades villages. Light and heat are also reflected by the annual whitewashed surfaces. Furthermore, the heavy masonry architecture provides extremely stable interior conditions that are desirable in summer [1]. In this type of vernacular architecture, some facades are completely without windows and some others have small openings for ventilation and lighting. Social areas that need sufficient light have larger windows compared to sleeping areas, which have tiny openings. An interesting feature of light management, which can be also found on the tower type, is the widening of the window sides and sill towards the interior for glare control [6]. However, there are two architectural features that the Cycladic vernacular did not adopt, which are very common in other places with the same climatic conditions. There are no shadowing-shelters over the openings and no loggia. Both are prevalent in the Mediterranean area. 5.2 North-Hellenic tower type: environmental qualities The North-Hellenic tower type offers numerous methods of temperature and sun control: the separation of summer and winter zone and the use of loggia and sahnisin along with the opening size and the proper orientation. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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The main characteristic of this type is the inter-seasonal use of different spaces. The houses were divided into summer and winter zones. The winter zone was either on the lower level (stone structure) or on the upper level coexisting with the summer zone, while the summer zone was situated on the upper level (timber structure). The winter zone had a lower ceiling, fireplace and southfacing windows. The size of the openings was small and used mostly for ventilation and lighting in wintertime. Shutters were not common because the light was desirable during the short winter days. In the winter zone, the minimum internal air temperature is maintained at high levels compared to the very low ambient temperature in winter due to the high thermal inertia of the overall structure [8]. Contrary to winter zone, the summer zone had numerous large and cross-ventilating windows. The shutters were absolutely necessary in order to avoid overheating. Sometimes, this space was completely open on hot days. An interesting element of the summer room was the clerestory windows, as shown in figure 2, additional openings above the conventional windows for exploiting sun luminance. During the summer day, the large windows were usually shuttered and only the clerestory windows lighted the space. Hagiati functioned as a shaded balcony in summer protecting the interior from overheating and a sun space in winter allowing the lower sun of winter to penetrate for solar advantage [3]. Sometimes, it was closed in winter and open in summer in order to adjust to two different environmental conditions. Consequently, it combines the advantages both of the enclosed and open space. Additionally, it was a place for socialising, especially in winter days. People gathered for discussion and lunch or dinner. Sahnisin was created for functional reasons: the lack of sun lighting in residential buildings. The built-up area and the irregular streets did not allow direct sun lighting of the houses, so these solaria were an answer to this problem, and their name (solaria) proves their origin [5]. This space with at least two large windows and a few fanlights, positioned usually to the south or east on the upper floors, was the main summer room of the dwelling. The daylighting conditions on the upper floors are considerably better than of those on the ground floors [9]. Another problem it solved was that of the lack of space on the upper level. This extension could increase the size and orthogonality of the upper level to the main street of the settlement. As a result sahnisin also offered protection from the sun and rain to pedestrians. 5.3 Discussion and summary Summing up the basic architectural characteristics and the methods developed for sun protection and temperature control of the two types, some interesting conclusions emerge. To begin with, these two Hellenic types constitute two completely different architectural approaches, even if they were both developed at the same time and are adjacent to each other. This is due to the fact that they are two architectural results that evolved from a specific social, environmental and cultural background. The different sites, the climatic variations, the use of the local materials, and the influences of other cultures entailed the formation of a particular type in a particular place. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Figure 7: Shading diagram of Cyclades dwellings (Santorini example).
Figure 8: Shading diagram of Tower dwellings.
In both cases, the local architecture has endeavoured to establish a dialogue with the environment. Both styles make efforts to answer some of the environmental problems. In particular, the North-Hellenic Tower dwelling tries to adjust to seasonal climatic differentiations and to be more ‘flexible’ to temperature variation developing special architectural elements, such as hagiati and sahnisin. On the contrary, the Cycladic dwelling is more concerned with sun and summer season. More specifically, the sahnisin in the Tower type welcomes the summer sunlight, as it is illustrated in fig. 8, while the long eaves and the shuttered windows prevent the interior from overheating. In addition, the hagiati works as a shaded balcony in hot summer days. On the other hand, the Cycladic type uses small windows to reject the sun and whitewashed surfaces to reflect the sunlight, as it is depicted in fig. 7. Both types refuse the winter sun due to the limited number and small size of openings, even if the windows are unshuttered. Comparing the two Greek styles, the Cycladic dwellings are more picturesque and photogenic. Representative examples of this popular architecture are displayed in numerous books and magazines. These “villages in the sun” are universally known after Le Corbusier’s journey to the islands of the Aegean. He discovered a public architecture influenced by trading and past occupations and he continued to draw upon this experience throughout his architectural work. The inspiration of many modern and contemporary buildings derived from Le Corbusier’s projects. To the contrary, the Tower dwellings are not well-known and scenic, and did not inspire the work of many architects. Despite that, these buildings are more complicated, sophisticated and integrated. This type shows an architectural maturity in its many morphological, topological and functional elements. Specifically, the Tower style experienced adjustment to environment and climate to face social problems and to distinguish the different ethnic groups. The windows were a case in point. Shuttered windows were typical in a Hellenic residence, while unshuttered windows were popular in Ottoman dwellings. These buildings were more “flexible” and adaptable, because they could support the needs of a small society including open and closed, private and public space, WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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contrary to the Cycladic cell-like buildings, which distributed within a settlement.
6
Conclusion
This study has shown that both types have many qualities. The vernacular architecture was sophisticated enough to answer to numerous environmental and social questions. These styles were developed in response to local and regional characteristics, as well as social and cultural requirements. In addition, it is imperative to study not only stylish buildings, but also less elegant and cosmopolitan houses. It is possible that many sophisticated architectural answers are hidden behind the appearance. Consequently, the study and analysis of vernacular houses will renew both the relationship with traditional thought and the structural rationale of the past and finally will teach us ways to confront environmental questions.
References [1] [2] [3] [4] [5] [6] [7] [8]
[9]
Oliver P., Encyclopedia of Vernacular Architecture of the World, Volume 1 & 2, Cambridge University Press, Cambridge, pp. 134-135, 144-145, 155-156, 1462-1464, 1490-1495, 1540-1551, 1997. Atrosenko V.I., M. Grundy, Mediterranean Vernacular, a Vanishing Architectural Tradition, Anness Publishing, London, pp. 14-19, 96-116, 138-140, 1991. Goldfinger M., Villages in the Sun: Mediterranean Community Architecture, London, pp.9-24, 1969. Philippides D., Greek Traditional Architecture-Cyclades, Volume 2, Melissa, Athens, 1998. Moutsopoulos N.K., Traditional Architecture of Makedonia, 15-19th century, Paratiritis, Thessaloniki, pp. 22-23, 30-36, 42-51, 1993. Kizis Y., Domestic Architecture in Pelion (17-19th c.), ETBA, Athens, pp. 523-529, 1994. Fathy H., Natural Energy and Vernacular Architecture, the University of Chicago Press, Chicago and London, 1986. Oikonomou A., Winter Thermal Comfort in 19th century Traditional Buildings of the Town of Florina in North-Western Greece, PLEA 2005: the 22nd Conference on Passive and Low Energy Architecture, Lebanon, 13-16 November, pp. 353-358, 2005. Oikonomou A., Daylighting in 19th century Traditional Buildings of the Town of Florina in North-Western Greece, PLEA 2005: the 22nd Conference on Passive and Low Energy Architecture, Lebanon, 13-16 November, pp. 359-364, 2005.
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Examining line as a heuristic device in the design ethos of Alvar Aalto P. Harwood Department of Architecture, Ball State University, USA
Abstract The significance of line in Alvar Aalto’s design method must be looked at critically as any interpretation of his work lies in the expressionistic, iconological, wavy line sketches so integral to his process. Looking at Aalto’s experiments in wood, glass pieces, furniture design, drawings, and built works, I will illustrate that the line is the experimental media that serves as a point of departure for arriving at a symbiosis between nature and culture, defining everything from the topographical character of a roof line to the tectonic form of a door pull. His upbringing, family life, homeland of Finland, and drawing technique all influence his design method and built work. In this paper, the line is explored as a heuristic device provoking questions and providing insight into Alvar Aalto’s way of experimenting and intervening in land, in light, and in life. Keywords: regionalism, environmental architecture, Scandinavia, Finland, Alvar Aalto, modernism, architectural design.
1 Experimenting and intervening in land The strongest impressions Aalto received were “from his parents, his childhood, and the surroundings he grew up in. These were the sources on which he drew all his life.” (Schildt [1]). Born in 1898 in a small village in eastern Finland, Aalto grew up in the town of Jyvaskyla, the unofficial capital of the densely forested Lake District in the heart of Finland. The landscape of this meandering terrain is punctuated by sweeping curves of lakes weaving with forests that lend the region its distinctive character. Goran Schildt has written extensively on the influence of Aalto’s contextual and familial background on his tradition of building. Aalto’s grandfather was a certified forester and a teacher at Evo Forest
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104 Eco-Architecture: Harmonisation between Architecture and Nature Institute. Aalto’s mother followed in the forestry profession and married the surveyor J.H. Aalto, thus uniting the two disciplines.
Figure 1:
Kiruna Town Hall.
Figure 2:
Imatra Church.
1.1 The contour line The effect of his father’s surveying practice and mother’s forestry background is undoubtedly embodied in Aalto’s propensity to use the contour line to delineate both landmass and topographical form. This formative experience provided Aalto with an elementary exposure to native construction materials and techniques, sustainable practices and forestry conservation, as well as acquaintances with drawing and technical factors related to land surveying. In looking at Aalto’s concept sketch for the town hall at Kiruna, fig. 1, it is informative to see how strongly the mapmaker’s line asserts itself and how he “seems to build up forms as if he were marking the stepping contours of a mountain or hillside,” clearly occupying the space of each line as a habitable terrace at vertical intervals as he draws (Hewitt [2], pp.162-176). Suggesting reciprocity between building and landscape, lines of paths, steps, flora and site contours are drawn with equal weight. The sensibility with which Aalto uses this contour line to adapt his buildings to the terrain and the sky and to plan built form and land form as an interwoven fabric is clearly informed by his acquired feeling for the lie of the land and its representation in topographic maps. “There is but one rule holds in architecture, build naturally,” writes Aalto. “Our buildings should be placed in the landscape in a natural way, in harmony with its general contours.” (Aalto [3], p.21). Saynatsalo Town Hall illustrates how sensitively the contour line that defines the courtyard promontory rises out of the surrounding forest and acts as the perch upon which the honorific council chamber projects. The fluid contour of the chamber’s roofscape greets the sky as a jagged mountain, highlighting the major space within the building from the exterior. Shaping the mass as one would shape the land, the contour line then defines and adjoins entities in a series WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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of topographical forms, grouped around the central court. Similarly, the Town Hall at Seinajoki follows the organic pattern established at Saynatsalo, but here a blue-tiled wall is used to order the spaces that surround the inner court. This rustic, grassy, contoured hill steps diagonally up to the ceremonial cliff-like mass of the council chamber and visually connects you to the vertical axis of the bell tower beyond, even as a broad road serves to separate the two. The contour line was a way for Aalto to shape form, unite space and mass, and willingly express how buildings sit in the earth and get rained upon as they silhouette the sky. In material terms, these nitty-gritty issues were abstracted as Aalto took flashings, copings, and base courses and turned them from necessity into poetry. 1.2 The undulating line The irregular coastline, numerous lakes, and seemingly unending wilderness of the Finnish context is of further importance in understanding the alliances Aalto established between the land that he grew up in and the undulating line that characterized his architectural idiom. This context undoubtedly pre-disposed Aalto towards an interest in nature, especially as he sought to create figured interior landscapes in his work. Symbolically, the undulating line between water and land, and forest and clearing became a metaphor for Aalto, translated into the wave-like wall and ceiling of Imatra Church, fig. 2, the sinuous wall of the Worker’s Club redbrick façade, and the undulating balcony form of Essen Opera House. More than contriving a stylistic motif, however, this undulating line is intrinsic to Aalto’s work as a means to achieve a harmonious accommodation between man and nature (Weston [4], pp.98-122). Aalto writes, “Architecture should always offer a means whereby the organic connection between a building and nature, including man and human life is provided for.” (Aalto [5]). The Finnish Pavilion for the 1937 World Exposition in Paris became Aalto’s first unmistakable metaphor of the forest edge. Here, a single, undulating line running diagonally across the rectangular volume becomes the parti for the winning entry entitled Northern Lights. Goran Schildt describes this serpentine space literally as “a forest space, related to the spatial experience of wandering among tree trunks, rocks and bushes in the broken terrain of a Nordic forest.” (Schildt [6]). Another metaphor suggested by Richard Weston compares the billowing forest wall and reflective lake floor to a painting of the aurora borealis by Norwegian artist Peder Balke, noting a “striking resemblance to the snaking, closely striated form Aalto adopted.” (Weston [7], p.64). Whatever the inspiration, the uniqueness of the Finnish context is illuminated in this inspired installation. Clearly connected to Aalto’s experience of the northern forest, the organic, non-geometrical perception of space acquires particular poignancy in the interior landscape of the Villa Mairea. A common Aalto motif is to cast major internal spaces as ‘outdoor rooms’ as is seen in the main floor of the villa, where the interior can be read as a metaphoric forest (Weston [7], p.63). Aalto individualized all the columns, singly, in pairs, or in a clump of three, wrapped with rattan, clad with pine slats, or painted black steel, transforming the Cartesian logic of the regular column grid into a series of ‘forest fragments.’ In WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
106 Eco-Architecture: Harmonisation between Architecture and Nature the undulating screen band that separates the library from the main space, lines of light as rays, streak across the ceiling like sunlight penetrating the forest edge. Commenting on this organic line, Aalto writes, “that curving, living, unpredictable line which runs in dimensions unknown to mathematicians, is for me the incarnation of everything that forms a contrast in the modern world between brutal, mechanicalness and religious beauty in life.” (Aalto [3], p.49). When used in conjunction with the familiar contours of the surveyor’s line and the gestural sketches of his exploratory design method, the syntax of the undulating line becomes native to his work. 1.3 The speculative line Aalto was compulsively speculative in his design process. His searching, builtup lines were used to contour mass and space in plan and section, often building a figure out of the page as he explored complex formal patterns. The tentative, soft pencil line ‘idea sketches’ of his projects appear alongside formal presentation drawings, paintings, and photographs of his work in the book Synopsis, that Aalto himself helped lay out (Hoesli [8]). Aalto utilized the ‘exquisse’ technique, a tiny plan surrounded by projections into section, elevation or perspective, as the starting point for each project (Hewitt [2], p.166). Once he determined his concept through speculative sketching, he would entrust the work to an office assistant who “in close collaboration with Aalto would translate the sketches and pictorial explanations into a presentable conceptual plan.” Supervising the intervening stages of design development, Aalto returned to the project at “the phase of cultivating the building with refining details.” allowing the distinct Aaltoesque quality of space to become evident. (Fleig [9], p. 9-11). Aalto favored the soft media of charcoal crayon and the 6B pencil for his exploratory line work, suggestive of varying textures of material, flora, and light. Drawing as if by instinct, Aalto’s chubby pencil moved fluidly over the paper. His speculative line traversed all corners of the sheet, exploring every aspect of the design, and filling the entire page with multiple representations. “The Creator created paper for drawing architecture on,” Aalto exclaims. “Everything else is, for my part at least, to misuse paper.” (Aalto [10], p. 7). The childhood experience Aalto recalls most vividly concerns the white table at which his father, mother, and their collaborators worked. “The white table is big, possibly the biggest table in the world. And it stands in the biggest room in my parents’ home.” As he was to explain later in his career, the white table became a symbol for Aalto, “a neutral plane in combination with man, so neutral a plane that it can receive anything, depending on man’s imagination and skill. A white table is as white as white can be, it has no recipe. The white table of my childhood was a big table. It has kept on growing. I have done my life’s work on it.” (Aalto [3], pp.11-12). Whether drawing a stair rail detail or the building’s ‘parti’, the ‘white table of Aalto’s childhood’ was a way of interrogating the design. Aalto let the speculative, abstract line-work edit his evolving ideas and test the validity of form. (Schildt [11], pp.10-13). In multiple views of the Church of WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Lahti, emerging lines tracing plan shapes, masses, and contours of land and building form are shown with remarkable scalar accuracy. In a rich analysis of Aalto’s drawing technique, Mark Hewitt writes, “Although the apparent spontaneity of the line is suggestive of a purely speculative method, most of the published sketches follow a predictable problem solving system” based upon earlier training in surveying and academic architectural design. (Fleig [9]).
Figure 3:
2
Section of Church of the Three Crosses in Imatra.
Experimenting and intervening in light
The Nordic experience of light is unique. “The sun does not rise to a zenith but grazes things obliquely and dissolves in an interplay of light and shadow.” (Norberg-Schulz [12], p.1). This dispersed light highlights fragmentary and boundless space as places conceal their figural effect, creating spaces of moods and shifting nuances. Aalto’s work demonstrates that he had an acute awareness for this quality of light, not only as it occurs in the Finnish landscape and is reflected in his interiors, but also as it relates to humankind spiritually. 2.1 The double line Exploring how we can link the interior and exterior of our homes, Aalto discusses the thick, demarcating line that in Nordic climates “requires a sharp differentiation between the warm interior and the surroundings” and unites the more intimate rooms with the open air (Aalto [3], p.50). Recalling his own childhood home, Aalto believed that when entering a room you should sense the unity of the room, the external wall, and the garden. He understood that the cold climate might do violence to this unity, but that there is nothing wrong with Nordic homes being closed to the outside world. “The Finnish home should have two faces. One is the aesthetically direct contact with the world outside; the other, its winter face, turns inward and is seen in the interior design, which emphasizes the warmth of our inner rooms.” (Aalto [3], pp.51-52). This double-faced line is well illustrated in the Finnish National Pensions Institute in Helsinki. The external façade facing Mannerheimintie reveals an WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
108 Eco-Architecture: Harmonisation between Architecture and Nature austere composition of a ground floor public entrance sheathed in copper and bronze with solid exterior doors, sealed like a vault. Once inside, however, the intermediate space sharply contrasts the somber exterior in material, color, and mood. The main hall beyond is surprisingly arresting, a vast, internal court filled with daylight spilling downward from four large, trough-like, multi-layered skylights. This double line defining two ‘shells,’ fig. 3, is also used to tremendous success in the Church of Three Crosses at Vuoksenniska where Aalto creates a space of light in the dimension between the interior and exterior walls. Horizontal light, filtered through the birch and pine forest enters high in the double-layered windows of the east elevation, bounces against the shallow white space, and fills the sanctuary with a diffuse ‘half-light.’ The configuration of the three bulging swells in plan is analogous to the double-line ripples of the sanctuary ceiling. Following this descending, wave-like line in section, the altar roof peaks southward from the crown of the nave like a rock projecting from a shallow river. The formal reference to cascading movement reinforces the meaning of ‘vuoksi’ as flowing water, the name of the river that runs through Imatra, as well as the Finnish word aalto meaning ‘wave’ (Nerdinger [13], p.20). 2.2 The fragmented line In Finland, the land of the midnight sun, the diffuse white-light of a summer night is bewitching as the palpable dissolves in an enigmatic shimmer. Something analogous happens in winter when the snow covered earth and large sky vault saturate the night with a peculiar dark light. Indeterminate and fragmentary we inhabit a realm without fixed boundaries or clear geometric form. Things do not appear individually, but are interwoven. Spatially, “we are cleft into fragments of disparate character.” (Norberg-Schulz [12], p.6). This heterotopia of dissimilar entities is a particular curiosity with Aalto’s work, as is pointed out by Demetrius Porphyrious. (Porphyrios [14]) In the Cultural Center at Wolfsburg, a number of geometric coherences are brought together as if by chance, be it the radiating fan of lecture rooms or the introverted stepped library and the uneven orthogonal grid of offices. Discontinuities are welcome. There is autonomy within every ordering gesture as fragmentary lines of space and light define an intimately nuanced network of places. The Library at Seinajoki is a similar composition of fragmented lines brought together in light. The spatial organization shows the sunken reading area with its central control desk, a volumetric, figural library hall with a fan-shaped wall admitting dappled sunlight through horizontal louvers, and a low lying block of support spaces. A fragmented, undulating ceiling line distributes reflected light throughout the interior, referencing the typical northern sky of shifting clouds and broken sun (Weston [4], p.184). As these examples illustrate, the building’s interior becomes highly differentiated, leaving the monolithic order of Modernism behind. Aalto’s use of the fragmentary line lends great variety, spatially, formally, and materially, offering a rich palette to his buildings, capable of adjusting to all sorts of indeterminate circumstances. As Mark Hewitt aptly puts it, “A unity of concept is achieved without sacrificing formal diversity.” (Hewitt [2], p.176). WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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2.3 The analytic line “I learned - at the age of four, I believe - the philosophy of pencil and paper,” Aalto writes (Aalto [3], p.12). Later in life, his acquired sketching penchant was used in conjunction with more formal, analytic design techniques. It is apparent in Aalto’s use of simultaneous plan, section, and elevation modes on a single drawing, for instance, that he assimilated well the lessons of the academic classical method from his Beaux-Arts influenced curriculum at the Helsinki Institute of Technology (Schildt [11], pp.68-82). Additionally, Aalto learned the conventions of picturesque composition as we note the perspective views of massing studied within the margins of a page. Aalto’s extraordinary synthesis of space/mass composition in his conceptual sketch was the most powerful design tool in his repertoire. Mark Hewitt writes, Aalto’s “unique conceptual schema seemed to embrace the poetic qualities of form in drawing while simultaneously adhering to a precise, analytical methodology.” (Hewitt [2], p.177). Aalto understood that a loosely drawn sketch might uncover several alternative expressions of formal character and spatial enclosure, while simultaneously helping to refine the space between inner and outer walls and even articulate the acoustic and lighting design. To look at his drawing of space and light in a specific design is therefore informative in understanding this summarizing, analytic line. “When I designed Viipuri City Library,” Aalto writes, “I spent long periods getting my range, as it were, through naïve drawings. I drew all kinds of fantastic mountain landscapes, with slopes lit by many suns in different positions, which gradually gave birth to the main idea of the library building.” (Aalto [15], p.97). The spatial order of the library comprises various reading and lending areas, which are stepped at different levels with the administrative and supervisory center at the ‘peak.’ Layered within this interior landscape, the horizontal ceiling plane is fitted with circular skylights deep enough to prevent direct penetration of sunlight, fig. 5. Aalto’s childlike drawings of mountain landscapes were only indirectly linked with the architectural idea of Viipuri, but they led to an interweaving of the section and the plan shape, and to a kind of unity of horizontal and vertical construction (Aalto [15], p. 98). What is most intriguing when tracing the sketches of Viipuri library is the way that Aalto used the line to describe light, sound, and space in at once an analytic and experiential manner. This is seen in Aalto’s delineation of the acoustical form for the meeting room as well as the shaping of the conical skylights of Viipuri City Library, fig. 4. Lines of sound, like lines of light are projected and reflected from surrounding surfaces to achieve a unified diffusion in other works as well, most notably the shaping of the curved forms of Vuoksenniska Church and the fan shaped auditoria of Finlandia Hall in Helsinki.
3
Experimenting and intervening in life
Believing that “great ideas arise from the small details of life,” Aalto always designed with the day-to-day needs of people in mind (Aalto [15], pp. 94-95). WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
110 Eco-Architecture: Harmonisation between Architecture and Nature “My theory are my buildings, I build, that’s all,” is often quoted to explain Aalto’s untheoretical bent and focus on actual construction. Karl Fleig remarked that in the twenty-five years during which he spent countless hours with Aalto, he never talked about architectural theory. “What motivated him were his observations of life. Aalto attempted to invest everything with form.” (Fleig [9], pp.9-11) Others have pointed to the emotional qualities of Aalto’s expressionistic sketches as crucial to his view of design as an extension of life. “If form somehow fails to be logically connected with everyday life, it will suffer and loose significance,” Aalto exclaimed. “There are only two things in art: humanity or not” (Aalto [3], p.183, 202).
Figure 4:
Daylight and artificial light in Viipuri Library.
Figure 5: Idea sketch.
3.1 The horizontal line At the introduction to a lecture given to his British colleagues in 1950, Leslie Martin, vice president of the Royal Institute of British Architects introduced Aalto by referencing a ‘horizontal line.’ “Above this horizontal line I would choose to place the creative work of these great designers and below it the rest.” (Schildt [11], p.201). Aalto referenced Martin’s horizontal line in the same lecture saying, “The real line is to plan and to build for the little man, for his benefit.” (Aalto [3], p.204). Thinking about what people need, fresh air, daylight, gardens and forests, Aalto writes, “it is from these little things that we should build up a harmonious world for the people. This would be possible if everybody tried to get the people who are in the administration to just follow our line.” (Schildt [11], p.205). In the attention that Aalto played to the little things, from the tactile quality of a double door handle at a library to the dampened sound of splashing water in a washbasin at a hospital, it is apparent that he never forgot that he was designing for human beings. Here we are again reminded of Fleig’s comment that Aalto had “little time for formal architectural theories; only life that is lived and observed can furnish guidelines.” (Fleig [9], p.9). Life did offer guidelines for Aalto in the design of Paimio Sanitarium for he was ill at the time of its design. “It irritated me to lie horizontal all the time and WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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the first thing I noticed was that the rooms were designed for people who spend their days in a vertical position, not for those who have to spend days on end in bed.” (Aalto [3], p.178). As a foundation for the humanizing of architecture, Aalto based his design on this horizontal line of reclining patients. He designed the lighting to be outside patients’ field of view, ceiling heating to be directed toward patients’ feet, the ventilation of special opening casement windows to avoid drafts, the ceilings to be painted in dark, restful colors, the communal floor surfaces to be bright yellow linoleum to promote a sunny and upright disposition, sun loungers to be wheeled out to the open air terraces at the east end of each floor, and a wave-like chair with molded arm rests and a laminated wood supporting system to resiliently receive the occupant (Aalto [15], pp.76-79). 3.2 The meandering line The naturally flowing, seemingly self-evident, meandering line of movement is an important design element with which Aalto relates buildings to human beings. Aalto understood the way we orient in the density of the Finnish forest and in the uninhibited thickness of human life. We wander, because things are not precise. In this meandering line of movement, we come to find our way. As an expression of life and motion, Aalto’s ‘forest spaces’ allow us to find a tentative, wandering way. One never moves along an axial line, following an orthogonal route system from one point to another. Instead, the line of movement constantly turns off in a different direction, with the vitality and variety of nature expressed in the freedom of modulated and attenuated space (Nerdinger [13], pp.20-24). Like the asymmetrical fan-like form akin to many of his works, the flow of movement is like a subsiding wave, pulsating in and out, up and down, forward and backward. Aalto translates the everyday movements of people into architecture, applying this principle particularly well to the design of interior landscapes. In the figured space of Finlandia Hall, we see how the rectilinear concert hall forms are thrust into the public space creating wave-like, billowy lines of access, lending the interior a feeling of natural form and movement. This meandering line can also be seen in the form and experience of the Baker House Dormitories at Massachusetts Institute of Technology where every step and view is carefully choreographed. “The starting point of Aalto’s design was to place the living accommodation as well as possible in relation to the river,” Elina Standertskjold noted. “He made dozens of sketches and finally adopted an unusual plan in which the narrow spine of the building twists in parallel with the river road.” (Standertskjold [10], pp.56-63). This serpentine form resulted in an individual view of the Charles River from every room, wandering passages between public and private spaces, and an organic contrast to the rectilinear design of the MIT campus. 3.3 The indivisible line Aalto regarded everything that touches human life as a task for the architect and he referred to this process as the total synthesis (Fleig [16]). Seeing architecture as a single indivisible line, from painting to urban planning to experiments in WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
112 Eco-Architecture: Harmonisation between Architecture and Nature wood to the design of a staircase balustrade, is a special quality of Aalto’s work. Aalto understood every construction as an integrated whole, designing everything down to the smallest detail himself. Commenting on the inseparability of art forms, Aalto writes, “Paintings and sculptures are all part of my working method. So I wouldn’t like to see them separated from my architecture. To me these works are all branches of the same tree, the trunk of which is architecture.” (Aalto [3], p.40). In much the same way as Aalto’s paintings experiment with the natural metaphors of form and movement, Aalto’s bent wood studies and furniture design subtly but effectively transform industrialism into a harmonious quality of civilization. The fusion of sketching, painting, sculpture and architecture yields a dense web and complex mode of conception where the line is a unique heuristic device allowing Aalto out of the ‘maze’ when he gets that kind of “three in the morning feeling.” Aalto writes, “I forget the whole maze of problems for a while. I then move into a method of working that is very muck like abstract art. I simply draw by instinct, and in this way, on an abstract basis the main idea gradually takes shape.” (Aalto [3], p.108). Then “one tackles the material. Through application the ideas will become more concrete and realistic. The three art forms, architecture, painting, sculpture, are connected because they are an expression of human intellectuality based on ‘materia.’” (Aalto [3], p.267) Idea becomes reality as the indivisible line takes material form.
4
Conclusion: “Following the Line”
Aalto was fascinated by lines; as the strata and contours of the earth, as manifestations of natural forces, as expressions of meandering movement, as undulating wave-like spaces, even as striations of an uneven brick façade. In all his works, Aalto writes, he sought to “accentuate the lines of square and street perspectives. In the country, their function is to accentuate the landscape.” (Aalto [3], p.22) Uniting building and landscaping with a cartographers eye, combining speculation with rationality in an imaginative way, harmonizing space and mass with environmental sensitivity, and fusing form and function with remarkable human compassion, Aalto used the line in a heuristic way. What makes the line magical, Marja-Riitta Norri, director of the Museum of Finnish Architecture ponders? “The line contains human thought, it carries the mark of the hand that drew it; they combine into a single living material that goes to build the real world.” (Norri [3], p.9) Aalto’s theory is his process, he builds when he draws!
References [1] [2]
Schildt, G., “Alvar Aalto’s teachers – three leaves from the book of his life,” Alvar Aalto 1898-1976, ed. Aarno Ruusuvuori, The Museum of Finnish Architecture: Helsinki, pp. 13-21, 1978. Hewitt, Mark A., “The Imaginary Mountain The Significance of Contour in Alvar Aalto’s Sketches,” Perspecta 23 The Yale Architectural Journal, WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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[3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16]
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eds. M. Chapman, B. Rubenstein and S. Wright, Rizzoli International Publications: New York, 1989. Aalto, A., Alvar Aalto In His Own Words, ed. Goran Schildt, trans. Timothy Binham, Rizzoli International Publications: New York, 1997. Weston, R., Alvar Aalto, Phaidon Press Limited: London, 1995. Aalto, A., “Nature and Architecture,” Alvar Aalto 1898-1976, ed. Aarno Ruusuvuori, The Museum of Finnish Architecture: Helsinki, p. 34, 1978. Schildt, G., Alvar Aalto: The Decisive Years, trans. Timothy Binham, Rizzoli International Publications: New York, pp. 131-132, 1986. Weston, R., “Between Nature and Culture: Reflections on the Villa Mairea,” Alvar Aalto: Toward a Human Modernism, ed. Winfried Nerdinger, Prestel Verlag: Munich, London, New York, 1999. Hoesli, B. Alvar Aalto: Synopsis, Birkhauser Verlag: Basel, Boston, Stuttgart, p. 5, 1980. Fleig, K., Alvar Aalto: Volume II, 1963-70, Artemis: Zurich, 1971. Aalto, A., The Line: Original Drawings from the Alvar Aalto Archive, ed. K. Paatero, trans. H. Hawkins, Helsinki, 1993. Schildt, G., Alvar Aalto: The Early Years, trans. Timothy Binham, Rizzoli International Publications: New York, 1984. Norberg-Schulz, C., Nightlands: Nordic Building, trans. Thomas McQuillan, MIT Press: Cambridge, London, 1996. Nerdinger, W., “Alvar Aalto’s Human Modernism,” Alvar Aalto: Toward a Human Modernism, ed. Winfried Nerdinger, Prestel Verlag: Munich, London, New York, 1999. Porphyrios, D., “The Ordering Sensibility of Heterotopia,” Sources of Modern Eclecticism, St. Martin’s Press: London, pp. 1-8, 1982. Aalto, A., “The Trout and the Mountain Stream,” Sketches: Alvar Aalto, ed. Goran Schildt, trans. Stuart Wrede, MIT Press: Cambridge, London, 1978. Fleig, K., Alvar Aalto: Volume I 1943-63, p. 6, 1995.
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Historical influences of wind and water in selecting settlement sites P. Kilby Fellow of the Royal Institute of British Architects, Member of the Institute of Historic Building Conservation and Fellow of the Wessex Institute of Technology, UK
Abstract Air and water are the essential ingredients of all life and throughout history the choice of sites for settlements, whether secular or ecclesiastical, comes down to these two factors The influence of prevailing winds is significant and contains some elements of mystery or unexplained facts and the presence of a plentiful water supply again influenced where towns stood, not only next to rivers, but also where water from under ground sources was present i.e. artesian wells.
1
Introduction
The influence of prevailing winds in the location of a settlement can be seen, for example, in the first Roman settlement of Clausentum in AD 43, and the Saxon town of Hamwic, on the opposing bank of the River Itchen, that are sited in a line with the medieval walled town of Southampton on the banks of the River Test, all in a south-westerly direction, in line with the prevailing wind. Is this chance or design or has this notoriously persistent wind exerted a subliminal influence on this alignment? See Figure 1. Looking nearby at the City of Winchester, just 12 miles north of Southampton, it was created in AD 70 by the Romans with a new town called Venta Belgarum, when the River Itchen, on which it stands, was diverted and a whole new shape created where the grid layout of the town’s streets is tilted in a south westerly direction facing towards the prevailing wind; Figure 2. The presence of a plentiful water supply, whether from a river or an underground source, certainly influenced where towns stood. However, the abundance of
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116 Eco-Architecture: Harmonisation between Architecture and Nature
Figure 1:
This drawing represents the siting of the Roman Fort of Clausentum, The Saxon Town of Hamwic, and the later Medieval Town of Southampton, all sited in a south westerly direction.
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water on flat flood plains brought with it problems for medieval builders of cathedrals and monasteries where large structures needed support on unstable ground. Water was also a means of transportation before the coming of the railways, on rivers and man made canals, while the sea exerted its influence around the coasts. In Southampton, for instance, the prosperity of the medieval town up to the present day relied on the unique advantages of the dual tides, giving its port the advantage of 4 extra hours of high water first noted by the Venerable Bede, writing in the 8th Century AD.
Figure 2:
Venta Belgarum, today’s Winchester, was one of England’s ‘New Towns’ laid out on a grid, following the diversion of the River Itchen to accommodate the preferred plan, and tilted on a south west orientation.
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Climatic influences
Enquiries made with the UK Met Office, Jebson [1], have cast an illuminating insight into the relationship between weather and the built environment over the centuries. The source of the south westerly winds in the northern hemisphere relates to their origin at the equator, where warm air rises, and together with the forces of gravity and the rotation of the earth on its axis, has been driven throughout history towards the south west coast of Britain. These warmer winds have been recorded back to Roman times, not by any meteorological sources but by the strange and fortuitous evidence of vineyards growing as far north as Yorkshire. In Professor Lamb’s [2] scholarly book, ‘Climate Past Present and Future’, it confirms the influences of wind and rain, over the built environment for the period of the Roman Conquest, through to medieval times and beyond. Experience of the author over many years as a practicing architect in central southern England, has reinforced the view of the significance of the prevailing winds, especially in times of heavy and continuous rainfall, when rainwater against the envelope of building over a period of time, requires extreme design measures to keep the water from penetrating inside. There are other historical factors to consider namely the cycles of wet and dry periods and the reaction of structures comprising ancient settlements. During the period between 1100 and 1310, there is evidence of predominantly dry weather, mainly from the dendrochronolgy of trees, when Professor Lamb asserts “A climate event such as an extreme season can be dated in favourable circumstances to an exact year”. It is suggested that in this same period of Norman construction, that the failure of large building like Cathedrals and Churches may have been due to the lowering of the water table, and subsequent drying out and shrinkage of the ground on which these buildings stood. The most classic failure of a Norman structure in modern times is linked to Winchester Cathedral which almost collapsed at the beginning of the 19th Century, saved only by the endeavours William Walker a diver, the Consulting Engineers and Sir Thomas Jackson the Cathedral Architect, who said of the event, “From first to last, however, the history of the Cathedral has been marked with disaster owing to the unfortunate selection of the site”, (i.e. next to the River Itchen on it’s flood plain).
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The birth of settlements and their buildings
The earliest man made structures were simple timber frames with straw roofs and earth floors. There were of course no architects or planners to decide where a settlement should be founded. The first consideration was one of safety and we see in this, the Iron Age Hilltop Forts of St Catherine’s Hill south of Winchester dating from circa 300 BC and at Old Sarum nearby to Salisbury dating from about 500 BC. More solidly constructed buildings came first with the Roman occupation of Britain in AD 43, after their landing at Clausentum in Southampton Water and WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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setting up a fortified camp there on the site of, what is now, Bitterne Manor, making probably their first settlement here in this country. From this strategic position in southern England, would radiate the system of Roman roads, where during the occupation of 400 years or so, would extend over the whole country, including Wales and the lowlands of Scotland beyond Hadrian’s Wall in the North of England. It was along these roads that vast numbers of settlements grew in the guise of Villa homesteads, for which Rome was famous. Additionally this form of town planning brought with it the engineering expertise of the Romans, to introduce for the first time the technical installations of the hypocaust and steam baths, proper drainage and sanitation and all the refinements to deal with an inhospitable climate, unlike Rome, a place that was unlikely to be seen by its soldiers again. Further refinements in the organisation of town planning are seen in the layout of Venta Belgarum, i.e. Winchester as we know it today, where the tilt on the axis of the plan to the south west can best be attributed to allowing the prevailing wind free access across the grid of streets forming in effect a ventilation system. In addition, to the north of the new town, a necropolis or ‘City of the Dead’ was created to avoid contamination of the water supply by burials and to protect the spirituality of the living world. The securing of a sustaining water supply was a key element in the founding of a settlement. In the case of Winchester, Venta Belgarum, the chosen site was next to the River Itchen, which in addition is groundwater fed, over a catchment area of some 400 square kilometres where rainfall soaks into the chalk substrata, and there forms a massive underground reservoir or ‘aquifer’. The Roman engineer’s would have known this when choosing this particular site for their new town. Almost a millennium later the same decision was reached when the monks founded the Benedictine Priory of St. Swithun here in AD 964, led by Bishop Ethelwold. Without doubt the most significant individual structures of the medieval period in England, and indeed Europe were ecclesiastical buildings. Architects as we know them were not known, or at any rate recorded. The building work was done by master masons, members of exclusive ‘Lodges’ within whose enclaves were refectories and workshops housing, in effect, a closed order of expertise, guarding their knowledge of the geometric rules of construction from the outside world. The names of some of these elite masons are known, for instance William de Wynford who in 1382 was responsible for organising work on Southampton Castle and later was to assist Bishop William of Wykeham in the remodelling of the nave of Winchester Cathedral. However, one exception to the rules of exclusivity is seen in the writings of Villard de Honnecourt (circa 1175-1240) a French master mason who has left behind some rare manuscripts in a ‘Lodge Book’, dealing with medieval building construction and methods, Curl [3].
4
Conclusions and final analysis
Referring back to the significance of the prevailing winds in the choice of settlement sites and orientation of the plan form, in a south westerly direction, WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
120 Eco-Architecture: Harmonisation between Architecture and Nature further evidence arises to support this theory. On the Isle of Wight, the medieval layout of the streets of Newport, the Island’s ‘Capital’, originate from the late 12th Century AD, when Richard de Redvers, Lord of the Isle of Wight, laid down a parallel street system, namely the High Street and Pyle Street, which has endured to this day. The orientation of this street system is in a south westerly direction, Shepard [4]. Richard de Redvers, quite clearly a property entrepreneur of his time, similarly laid out the foundations of Lymington, across the Solent on the mainland this time, with what has been described as a ‘single axial’ street, forming the nucleus of the present street system, laid out in a south west orientation. This layout is confirmed nearer to our time in history by the 1750 ‘Map of the Manor and Haven of Bewley (now Beaulieu), in Hampshire’, Figure 3. This same map includes a reference to the foundation of the shipbuilding town of Bucklers Hard on the Beaulieu River, when it states “Adjoining the Key (Quay) there is a good situation for a Town, on rising Ground, gravely soil, with plenty of fresh water”. It was here that Lord Nelson’s ship the Agamemnon was built in 1781, Montagu [5]. Quite clearly the availability of water both for drinking and transportation purposes has been a significant influence on the choice of settlement sites in the same way that wind and weather would seem to have both a practical as well as subliminal influence, although quite difficult to substantiate.
Figure 3:
Map of Bewley (Beaulieu) 1750. This 18th Century map clearly indicates the original axial plan of present day Lymington, (circled) (called Limington on the map), laid out in the 12th Century by Richard de Redvers, Lord of the Isle of Wight, again on a south westerly axis.
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In a recent television programme (2005) on BBC2 entitled “Talking Landscapes” the presence of unexplained prehistoric stone features above ground was explained by the significant statement “Belonging to a landscape results in a desire to replicate it with these structures”. Quite clearly there were influences beyond man’s comprehension in early history, when the forces of nature were a cogent element to be acknowledged and reacted to when creating a town or settlement on a virgin site. The wind direction was in effect a natural compass and one can find no other reasonable conclusion to explain the phenomenon of the south westerly orientation of some coastal settlements.
References [1] [2] [3] [4] [5] [6] [7]
Jebson S. Information Officer, UK Met Office, E-mail 22/09/05. Lamb H.H. Climate Past Present and Future, London, Methuen and Co Ltd, 1972. Curl J.S, A Dictionary of Architecture, Oxford, Oxford University Press, 1999. Shepard B, Newport Isle of Wight Remembered, Newport, Natural History and Archaeological Society, 1984. Second Lord Montagu of Beaulieu, Bucklers Hard and its Ships, London, 1909. Kilby P., Southampton Through the Ages, Southampton, Computational Mechanics Publications, 1977 Kilby P., Winchester an Architect’s View, Southampton. WIT Press, 2002.
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Unity, simplicity and balance: sustainable management of cultural historic environments of mountain summer farming G. Swensen The Norwegian Institute for Cultural Heritage Research
Abstract Ecologically based architecture aims to maintain a long-term harmony between the built environment and nature. It assumes that there is a close, interlocked connection between natural conditions and cultural expressions, a unitary and holistic comprehension of time and space, and a belief in one’s ability to influence the long-term effects of technological development in an ecologically beneficial way. In this paper these hypotheses will be viewed in light of some basic principles on which the structures of traditional building forms have been based. Special emphasis will be put on the relationship that has long existed between the built environment and the landscape. This approach will be illustrated by the presentation of a traditional regional type of dwelling still found in active use in some mountain areas in Norway and by the ways farmers adapt to the demands set by modern farming directives. The paper is linked to an ongoing interdisciplinary research project: “Redefining Rural Resources – Local capacity-building in sustainable management of cultural historic environments of mountain summer farming”. Keywords: cultural historic environments, cultural heritage protection, sustainability, ecological architecture, vernacular architecture, mountain summer farming.
1
Introduction
1.1 Main perspectives This article should be seen as a small contribution to the basic discussion on which cultural heritage management is based, namely how to secure a viable role WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060131
124 Eco-Architecture: Harmonisation between Architecture and Nature for enduring cultural historic environments in meeting the challenges set by modern forms of production. It is illustrated by a region where mountain summer farming still plays a vital role and the article primarily focuses on one aspect of mountain summer farming, namely the dwellings and the cultural historic environment and landscape of which they form an integral part. The mountain summer farm constitutes a cultural environment of material components: buildings and other built structures (fences etc), surrounding areas (pasture, mowing land), as well as immaterial connections. Today the owners find themselves in the intersection between several trends: agricultural readjustments leading to either a reduction in or the discontinuance of mountain summer farming – a developing tourism industry based on an appreciation of national heritage – and expanding areas of modern holiday homes and outdoor pursuit centres in key mountain regions. Are the characteristics of the built environments that are recognised as assets for local farmers commensurate with the technical demands, agricultural regulations, and economic framework to which today’s farmers have to adapt? The primary question in this context is: can the basic principles of forms, constructions and plans on which traditional types of dwelling are based be sustained and developed from an eco-architectural perspective to meet the demands today’s mountain farmers face, thus managing to maintain the tight-knit bond between landscape and forms of settlement? This paper is linked to an ongoing interdisciplinary research project: “Redefining Rural Resources – Local capacity-building in sustainable management of cultural historic environments of mountain summer farming” (2005 – 2007). Two case studies will be carried out in different regions with active summer mountain farming. The analysis will entail study at three different levels: 1. A critical review of relevant official documents and proposed and approved plans 2. Qualitative interviews with key actors participating in the local capacity-building process 3. A field study, including systematic observations in the selected localities. This article presents some reflections based on the first case study, with references to some of the key official documents as well as to information from some of the 13 interviews. 1.2 Presentation of some key concepts Discussions about sustainability reflect a growing concern for the environment. Place-based communities have become central to a holistic concept of sustainability which integrates environmental, economic, political, cultural and social considerations. It rests on a recognition that the safeguarding and preservation of nature and cultural environments must be grounded in the communities and societies which utilise and depend on them (Richards and Hall [9]). This strong emphasis on the local community constitutes the premise on which this article will be based. When sustainability is referred to in discussions about ecological architecture, aspects such as technology, renewability and traditional wisdom are focused on (Butters and Østmo [2], Williamson [16], Phillips [7], Thompson [14]). According to James Steel, the need for sustainable development has led to a new way of looking at materials and form, opening the way to a greater willingness to WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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replace scarce resources with renewable materials. This requires looking beyond fashion to a more durable approach to design. A more open minded attitude has moved the perspective towards learning from traditional building methods and realising “that local architecture grew out of many trial and error attempts to deal with natural phenomena and should be respected as a repository of wisdom” (Steel [11]). The sustainable management of cultural historic environments characterised by active contemporary use gives rise to examples where such knowledge is needed by the participants involved at all levels – farmers, builders, and management officials. The challenges being set by modern operating methods require the redefinition of cultural historic resources in a new setting, though on the terms stipulated by the old buildings and the context of their environments.
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Case study: Budalen – a region dominated by active mountain summer farming
2.1 A local example Budalen was selected as case study due to the active summer farming which has taken place here for generations. According to the list of farmers receiving production subsidies in the municipality, 28 farmers were practising mountain summer farming here in 2004. Of this total, 17 of the mountain summer farms are situated within a landscape protection area (Endal and Budal). In this part of the municipality the number of active mountain summer farmers has stabilised during the last ten years. Traces of mountain summer farming in this region can be found from as far back as the middle of the 17th century, and during the subsequent 200 years a series of summer farms were established. The main reason for the continuous summer farming is the need for supplementary animal fodder. The main farms are situated in a region where the summers are too short to provide enough cultivated grazing land for the livestock. During the peak summer months, normally between 1st July and 1st September, the livestock is moved into the valleys to supplementary grazing land in the mountainous area. The two valleys are reminiscent of two arms stretching out towards a remarkable mountain formation named Forollhogna. Endalen is situated in the western part of the region. It is a relatively open valley situated approximately 700 – 1,100 m above sea level and stretches over approximately 35 km. Today the valley has no milk round, which means that the dairy products have to be produced at the summer farms. There are three active milk farmers in Endalen, with the rest of the dwellings being run by sheep farmers. All the land in this valley is owned by the state. The eastern valley, Budalen, which has given its name to the whole region is slightly shorter than its neighbouring valley. A few of the summer farms are privately owned in its southern part. The daily milk round forms the economic basis on which today’s summer farming is based, though the so-called niche production of traditional milk products plays an important supplementary role. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
126 Eco-Architecture: Harmonisation between Architecture and Nature As a mountain region, Forollhogna is a popular habitat for large herds of wild reindeer and other rare wildlife. Because of this the region was turned into a protected national park in 2001. The two neighbouring valleys where the summer mountain dwellings are situated are listed as landscape protection areas, which means they are subject to restrictions concerning building alterations, rebuilding, etc. The main focus is still on the maintenance of active farming, which to a large degree influences how the regulations are interpreted and applied. 2.2 Mountain summer farming - a cornerstone of Norwegian agriculture From a situation 150 years ago where almost every farm had a summer mountain farm, and some farms even had more than one, about 1,200 summer mountain farms are currently in use (Norsk seterkultur 2003). The fact that a lot of farmers found it financially unsatisfactory to maintain mountain summer farming led to a dramatic reduction after 1945 due to major changes within the rural sector. Sør-Trøndelag, the county in which Budalen is located, had more than 2,000 active mountain summer farms in 1939. By 1998, the total number had fallen to 425. The threat this trend represents with respect to losing key assets has caused both the rural and the cultural heritage sector to act. Different forms of grants have therefore been introduced, both for community development and cultural landscape management. This has resulted in a slight increase in summer farming since the lowest level was reached in 1989, and between 1989 and 1998, 71 farmers decided to start up again in Sør-Trøndelag (Statens Landbruksbank [10]). The summer farming in Budalen typifies a Norwegian mountain summer farming region in the sense that it blends into a pattern of multifunctional agriculture that represents an adaptation to the particular climatic conditions farmers in this country have always had to face. At the same time its character makes it unique: partly because of the close-knit unity which still exists between the landscape and dwellings, and partly because of the strict regulations to which the summer farm region is subject as part of the landscape protection. The level of degradation has reached a higher tempo in most other regions.
3 Traditional buildings as part of today’s landscape 3.1 Some basic principles of traditional wood building techniques The importance of upholding certain general rules that govern the traditional use of wood as a building material was stressed in a recently completed project, which has led to a greater focus on how traditional techniques can be transferred to a modern setting. Particular attention is paid to principles such as: - The principle of adequacy, which states that the optimal quality of the raw material is that which is good enough for the job. While certain exposed parts of a building require top quality timber, others are adequately cared for by using poorer materials. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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- The complementary principle of protective construction, which pervades much of our architectural heritage and is embodied in numerous methods aimed at ensuring buildings maximum lifetimes (methods and constructive elements to ensure ventilation, combat rot, preventing the entry of water, etc.) (Egenberg 2004b:6) 3.2 A short description of the regional building traditions The mountain summer farms in the two valleys are located according to the topography. Unlike the main farm settlement, no distinctive farmyard structure dominates. There is however a slight tendency to place the buildings in a row, in which case the mountainous landscape formation often plays an important role. The Swedish architectural historian Finn Werne [15] has introduced group form as a concept in his studies of traditional peasant buildings. It describes an open and dynamic form in which new parts or elements can be added and others removed or changed without the unity or pattern being broken. Group form is characteristic of the building traditions in the old peasant society. It grew out of several social and particular phenomena, and is related to a complex network of routines, customs, traditions, knowledge, motivations, roles and material preconditions. It is typical of ordinary building constructions and is significantly distinct from architecture as a formalised art form. A mountain summer farm in this area normally consisted of three main building types: a house built as a combined dwelling and storehouse (“seterbu”), a cow barn, and a hay barn. In addition to this, separate cookhouses and storehouses were common on most mountain summer farms. Smaller hay barns were also situated outside the building cluster nearer to the hay outfields. The combined dwellings and storehouses were quite small, between 4-5 m long. They normally had three rooms. The entrance led into a combined hall and storehouse (“skjæle”) and from here into the room with the fireplace, a room combining several functions: cooking, sleeping and recreation (“bu”). On the other side was a cool storehouse (“masbu”) without windows for storing dairy products. The outbuildings were generally laid out as one-storey buildings with one room. There are also examples of combined outbuildings, for instance cow barns extended with hay barns. A few cow barns had a cellar for manure, but more commonly there was an opening in the gable wall. Most buildings had natural stone foundations or rested on cornerstones. The construction method most frequently used was cogged joints, often in combination with a timber framework. To keep the roof waterproof a layer of birch bark was placed between the roof boards and a layer of turf. These old techniques fell out of use when galvanized sheets were introduced. The buildings were designed to be utilitarian and ornamental details were only sparsely incorporated (SørTrøndelag County Council [12]:6-9). 3.3 Restrictions set by the landscape protection regulations Since many of the areas are owned by the state, a special set of rather strict regulations apply (“Seterforskriftene”). However, there is a willingness to open WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
128 Eco-Architecture: Harmonisation between Architecture and Nature the way for new activities aimed at producing supplementary income such as tourism and culture based services. There is an assumption that such combinations are necessary to maintain mountain summer farming. The active milk farmers today use generators to run their milking machines, and solar panels for general lighting. Permission has been granted for the provision of electricity to the valley in the future. Buried cables have been recommended, but financial considerations are currently preventing installation (Forvaltningsplan [6]: 17, 18). When it comes to the buildings, the importance of protecting the landscape against interference (for instance erecting new buildings, demolishing old farm buildings) is highlighted as the primary function. Room has however been made for exceptions and such applications are generally accepted when their purpose is to erect buildings that are necessary to enable summer farming and grazing, or to allow either restoration or rebuilding for farming purposes. It is also possible to apply for permission for a change of use. Except in the case of ordinary maintenance, all applications concerning the dwellings are considered by cultural heritage officers at a county level (Forvaltningsplan [6]: 19-21). 3.4 Conflicting interests between conservation and modern farming? In a handbook published by the county’s cultural heritage department, the farmers are asked to take account of old building traditions when it comes to reparation, maintenance and new buildings. When it comes to new buildings, the importance of orienting them according to the longitudinal direction of the valley is stressed. In addition to this, extensions also have to be built lengthwise and not at an angle. Do such approaches represent a basis for conflicts? There are two main reasons why a need to alter a building arises. One is the need to add an extension to the combined dwelling and storeroom in cases where a farmer is hoping to rent out rooms to tourists. So far only one or two such cases have been handled by the municipality’s Building Inspection Department. The other major group of buildings undergoing reparation, alterations or rebuilding are the cow barns. Any buildings in which milk products are processed for retail are today classified as production buildings and have to meet the specifications set by the agricultural authorities. The requirement to conserve the old cow barns while complying with new demands has led to interesting experiments. The so-called “milking stable” complies with the detailed specifications concerning dimensions linked to the size of the herd. Old cow barns would neither be high nor bright enough to satisfy today’s standard. The milking stable is used as a temporary shelter while the milking takes place. The livestock is let out again as soon as the milking is over, and the time consuming job of removing manure no longer exists. Not all of the mountain summer farmers have found the milking stable experiment satisfactory. One argument against it is animal welfare, since cold mountain nights can be harsh. According to anecdotal stories, cows belonging to farmers with a milking stable tend to mix in with other herds in an attempt to get shelter. The new cow barns which are being erected to house a normal herd of between 12 – 16 cows need to be bigger than the old cow barns to satisfy current directives. A few such barns are WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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extensions of old buildings with stipulated height requirements being met by digging down and constructing new foundations. However, most of the new cow barns differ from the old in construction, length, dimensions and materials. A local builder specialises in erecting buildings with cogged joints. He is himself a mountain summer farmer. When he needed to restore some of the buildings on his own summer farm, he took courses so he could restore his own buildings. Today he is running a small building business and has delivered two buildings to mountain summer farmers in the two local valleys. There seems to be local demand for this sort of specialised knowledge, but no apparatus for channelling the demand in the right direction. Plans for using old buildings in new ways are normally approved by the municipality’s Building Inspection Department. At the moment there are new plans to restore cookhouses. Another idea planned for some time in the future concerns restoring a collapsed barn and turning it into guest accommodation. The financial backing which makes such plans possible is sought from several sources. An annual subsidy is distributed at the county level to all mountain summer farmers and there also are several other grants. You need a wellestablished network and good advisors in order to be familiar with these possibilities. The rural advisor employed by the municipality plays an important role here and is referred to by most of the interviewees. Being a part-time mountain summer farmer himself, he has an insight into the nature of the job, which is now largely aimed at combining active use and protection. Many other challenges faced by farmers on a daily basis stem from regulations concerning hygiene and health directives for agricultural food production. Those farmers who are interested in placing more emphasis than before on specialised milk and cheese production, have to comply with directives which are unsuitable for these goals. As one of the farmers put it: “We have to follow the same procedures in these mountain areas as a chef in a gourmet kitchen in the capital”.
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A discussion of mountain summer farms in relation to eco-architectural principles
4.1 Influence and local participation The legislation that ensures the protection of valuable areas contains an inbuilt potential for conflict, regardless of whether one is talking about natural resources or cultural heritage assets. The formal decisions are primarily made at a state or county level, which creates a need for constructive dialogue to enable local opinions and suggestions to be taken into account. Without an understanding of local factors much of the effort to ensure protection is likely to fail. Not surprisingly the initial discussions about protection where met with a lot of scepticism in Budalen. The farmers were afraid that strict regulations would impede active summer farming which had survived during a long period of continuous adjustments. During a period dominated by discussions the scepticism has slowly worn off. Now the dominant viewpoint seems to be an WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
130 Eco-Architecture: Harmonisation between Architecture and Nature understanding of the potential being generated. This is due to the engagement of several parties, not least initiatives at the municipal and county level. Active farmers are involved in courses and inspire each other to try new methods in accordance with handed-down knowledge. Due to a greater awareness on a national level of the cultural landscape resources at stake, recent changes to the government’s rural policies have made it easier to direct grants and subsidies towards active mountain summer farming areas. Thus new initiatives have been created which have resulted in a new optimism among the farmers. 4.2 Ensuring harmony between built settlements and the surrounding landscape The interviewees have surprisingly uniform opinions when asked what the main assets of the valleys are. The primary value they mention is the harmony that exists between the landscape and the settlement, which make it unnecessary – and impossible – to rank one particular settlement above the others. The explanation given for this is the continuous and vital role it plays in ensuring their daily income. Seldom is a consensus concerning cultural values so easily reached. In this case it can be understood in light of people’s shared perspective due to active practice in today’s landscape. It is based on an understanding of the dialogue and dialects which exist between nature and culture. In this case the use of the Nature Conservation Act can be seen as one of the available means of ensuring the continuation of the long established harmony between the built environment and nature. By specifying the importance of continuous active use in relation to modern rural demands, the regulatory documents reveal an underlying shared understanding of the importance of maintaining the unity of time and space to which the dwellings situated in the landscape bear witness. 4.3 The need for a new perception of the past Today, there is renewed interest in reviving elements from the past in most western countries. Some of this interest is based on expectations that tourism will create new economic opportunities in rural areas struggling with migration. Other reasons may have a political and ideological origin at a time when European countries are becoming more tightly woven into the fabric of the EU. In Budalen however, it is not a question of reviving, but of maintaining a way of living which has proven to be highly adaptable. During the last few years the population level has been stable. Most of the people living there regard themselves mainly as farmers by profession, even though the family economy is often supplemented by other incomes, and they want to continue as farmers for as long as an opportunity to do so exists. Getting young people interested in spending a summer season in charge of the mountain summer farm is not a problem, one of the youngest is a 17 year old girl. However, farmers in Budalen are well aware of the renewed interest in rural traditions in the tourism market and have an open mind towards new ways of combining farming, tourism and cultural tourism. The uniqueness of these valleys lies in the interplay which takes
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place here between traditional buildings and a landscape which, though dominated by biodiversity, is still in active use. 4.4 Promoting ecological friendly building forms and methods (“green structures”) Knowledge of the old ways of building is no longer shared knowledge because the long process of specialisation has given rise to a wide gulf between the location of production and the local market. Local craftsmen are often used in Budalen when it comes to erecting new buildings and rebuilding. But, when it comes to deciding which building materials, oils and paints to use, financial considerations count more than ecological ones. Protected areas represent an ideal basis from which to promote ecologically based solutions (“green structures”) and test the potential of influencing the long time effects of technological progress in an ecologically accommodating way. These decisions however have to be made on a different level than the local market in which tight financial margins leave no room for risky experiments. A national strategic programme for testing out ecologically based solutions in protected mountain summer farming areas would be an interesting test case to promote.
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Concluding remarks
The main focus of this article has been how the conservation of cultural historic environments can be combined with the practical contemporary use of the buildings in a satisfactory way from a social, financial and ecological point of view. By choosing the situation which occurs in the somewhat “ideal” setting of a landscape protection area as an example, the article illustrates some of the milder practical problems which occur when farmers try to combine an historical interest with the obligations today’s farming directives set. The interconnectedness which exists between landscape and settlement in the example region of mountain summer farming has been underlined as the major quality by all the parties involved in activities in this area. Those actively participating in the development of modern “taskscapes” (Ingold [5]) can find a lot of inspiration from traditional ways of building. A continuous and constructive dialogue concerning the adaptation of new building types and styles in conservation areas should be a requirement, and we should encourage proponents of ecological architecture to participate in this discussion. There is a need for more pioneers to develop solutions that can work within the new financial, social and ecological limits today’s farmers encounter. The “repository of traditional wisdom” inherent in cultural historic environments can be seen as a rich source of inspiring new solutions.
References [1]
Bladh, Gabriel 1995: Finnskogens landskap och människor under fyra sekler – en studie av natur och samhälle i forändring. Göteborg University. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
132 Eco-Architecture: Harmonisation between Architecture and Nature [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16]
Butters, C & F.Østmo 2001.Bygg for en ny tid. Mot en miljøvennlig arkitektur – 127 norske eksempler. Oslo: Norsk arkitekturforlag. Egenberg, Inger Marie 2004a. Tre i tiden. Tradisjonsbaserte løsninger. Oslo: The Norwegian Institute for Cultural Heritage Research. Egenberg, Inger Marie 2004b. Timber for Today. In: NIKU Annual Report 2004. Oslo. Available at http://www.niku.no Ingold, Tim 2000. The Perception of the Environment. Essays in livelihood, dwelling and skill. London/New York: Routledge Municipality of Midtre Gauldal 2005. Forvaltningsplan for Endalen, Budalen, Forddalen. Landskapsvernområder. Phillips, Christine 2003. Sustainable place. A place of sustainable development. Chichester: Wiley-Academy. Norsk seterkultur 2003: Seterbrukaren. Skrift frå Norsk seterkultur, nr.34/2003. Richards, Greg & Derek Hall (eds.) 2000: Tourism and Sustainable Community Development. London / New York: Routledge. Statens Landbruksbank 1999. Prosjekt seterbruk i Norge. Status og virkemidler. Rapport for fase 1. Steel, James 2005. Ecological Architecture. London: Thames & Hudson Ltd. Sør-Trøndelag County Council, Department of Culture 1994: Verneplanarbeide Gauldalsvidda Forollhognaområdet. Trondheim. Sør-Trøndelag County Council, Department of Culture 2002: Nybygging i seterlandskapet. En mini-håndbok for eiere av setrer i Sør-Trøndelag. Thompson, Ian H. 2000: Ecology, Community and Delight. Sources of values in landscape architecture. London/New York: Spon press: Werne, Finn 1993. Böndernas bygge: traditionellt byggnadsskick på landsbygden i Sverige. Stockholm Williamson, Terry, Antony Radford & Helen Bennetts 2003. Understanding sustainable architecture. London/New York: Spon Press.
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A tale of two city halls: icons for sustainability in London and Seattle D. Armpriest & B. Haglund Department of Architecture, University of Idaho
Abstract Recently two great cities—London and Seattle—have built new city hall buildings with a green agenda inspired by activist mayors—Ken Livingstone and Paul Schell. Their political agendas include a focus on planning and design activities that will help transform their cities for continued viability and livability in the face of increasing environmental challenges. In London, Livingstone carved out a congestion zone to allay mounting, gridlocked automobile traffic in the central city; it costs eight pounds a day to drive into central London. Meanwhile in Seattle, the city has implemented a green building agenda (LEED silver) for all public facilities, and the city has “signed” the Kyoto Accord in defiance of the Bush administration’s stance. These new city halls are intentional symbolic icons marking their evolving visions for the future. Comparing the two buildings will reveal much about the commonalities and differences in approaches to sustainability in the United States and United Kingdom. Through the lenses of first-hand experience in the buildings, analysis of critical commentary, and comparative evaluation, we examine the mindsets of the two cultures. The analysis includes several key project characteristics that provide the basis of the comparison, including the design process, building image, public access, sustainable design strategies, and performance in these exemplar buildings. Keywords: sustainable architecture, building performance, city halls.
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Introduction
London and Seattle are both similar and different in ways we believe speak to cultural attitudes on sustainability. Both urban hubs have set an agenda for sustainable development and have used new city hall buildings as exemplars. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060141
134 Eco-Architecture: Harmonisation between Architecture and Nature However, London chooses to take the lead in a country committed to reversing global warming while Seattle pursues sustainability against the grain of national policies that frustrate efforts to address global warming. Greater London is larger (12 million to 2 million) and denser than the Seattle Metropolitan area and its mass transit is much more extensive and successful—all factors that make sustainability more palpable. On the other hand Seattle has strong visual connections to its beautiful natural setting—vistas of the Olympic Mountains, Puget Sound, and Mt. Rainier—that serve as reminders of the fragile natural environment to be sustained. Both cities are sited in mild northern climates dominated by ocean influence that moderates temperatures, provides rain and cloud cover, and places high value on daylight and sunshine. These are favorable climates for attaining energy-efficiency in office buildings.
Figure 1:
London City Hall viewed from the west and Seattle City Hall’s office tower viewed from the northwest, comparing image and shading strategies.
The mayor’s vision is for London to become an exemplary sustainable world city, based on the three balanced and interlocking elements—strong and diverse economic growth; social inclusivity, allowing all Londoners to share in London’s future success; and fundamental improvements in environmental management and use of resources [8]. The Sustainable Development Framework for London, drafted by the London Sustainable Development Commission in 2002, proclaims, “We will protect and improve the city’s natural ecosystems, its biodiversity, its open spaces and its built environment. We will help to protect the wider regional, national and international environments with which London has links.” To this aim City Hall was designed as a sustainability exemplar, a congestion charge was enacted to discourage automobile traffic in central WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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London, and new planning regulations for large-scale development in Greater London that require that 10% of its energy be provided by on-site sources. The mayor exhorts be lean, be green, be clean when chosing energy sources. Seattle mayor Greg Nickels’ Environmental Action Agenda sets three goals— to create a “lean, green city government,” “healthy urban environments,” and “promote smart mobility” [17]. In February, 2005, he announced, on the day the Kyoto Protocol took effect, that Seattle would commit itself to meet or beat the goals of the agreement despite the failure of the United States to join the treaty . At this time, he also appointed a Green Ribbon Commission consisting of environmental, city, and business leaders to assist him in developing the plan. The Commission is reported to be considering following London’s lead in charging a fee to drive into the city [20].
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Design process
2.1 London A competition resulted in selecting a developer/architect team. The building was developed by More London (CIT Group) and leased to the GLA for 25 years. Designed by Foster and Partners, with Arup as structural and services engineer, it employed the UK’s most renowned green design team. “We designed the building from the outside,” says Foster and Partners project director Richard Hyams. The design was revised from the architect’s original all glass concept, dubbed the fencing mask, in response to sophisticated computer modeling by consulting engineer Arup who produced a “thermal map” to show how the heat from the sun would travel over the building’s surface throughout the course of a year. To reduce the building’s cooling requirements and thus reduce the building’s energy load, the architect refined the building’s form to a shape that leans to the south, so as to limit the extent of façade exposed to the sun. The southern elevation, which has the greatest potential for solar gain, has also been stepped so that the floor above cantilevers to shade the floor below, fig. 1. On the northern elevation, however, free from excessive solar gain, the architects have indulged in an unshaded façade [18]. 2.2 Seattle The City Hall was designed by a collaborative team that combined the local talent of Bassetti Architects with the nationally recognized green firm of Bohlin Cywinski Jackson (BCJ). They were selected through a competition process, beating out the finalists, Antoine Predock and Patkau Architects. The design process included 50 public meetings and workshops and a web-based system for public input. Local architect and city councilman Peter Steinbrueck claimed “the process almost killed this design” due to the challenge of responding to the extensive criticism [22]. Architectural critic Sheri Olson claims the design, which is touted by the architects and city as being grounded in the site and regional, is actually the same scheme the architects brought to their interview
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136 Eco-Architecture: Harmonisation between Architecture and Nature and changed very little as a result of the process. The design team did consult with the Seattle Lighting Lab to refine natural and electrical lighting strategies.
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Building image
London City Hall is an iconic building that competes for attention with nearby Tower Bridge and the Tower of London and is framed by the reflective background of More London, a commercial project Seattle City Hall is more modest in appearance, serving as background for its iconic neighbour, the Seattle Public Library. Both city halls were designed not only to demonstrate sustainable design, but employ generous glazing to portray an open and accessible city government, fig. 1. 3.1 London According to Foster and Partners, “City Hall has been designed as a model of democracy, accessibility, and sustainability.” [1]. Its eleven stories and 185,000 square feet (18,000 m2) house both the Chamber of the London Assembly (25 elected members) and the offices of the Mayor and 500 staff of the Greater London Authority, providing about 370 square feet per person. Completed in May 2002, it cost about $64,000,000 or $345 per square foot. The building has achieved an excellent rating in the BREEAM assessment. 3.2 Seattle The new City Hall is a seven story, 200,000 square foot building that houses the mayor, city council and a staff of 320. There are two stories of parking below ground, the majority of which are reserved for alternative fuels and carpooling vehicles. It was completed in 2003 for a cost of $72,000,000 and recently received a LEED Gold rating. As designed, the building provides 625 square feet per person, and cost $320 per square foot. The language used by city officials to describe the Seattle City Hall stated aspirations similar to those used to describe the GLA: “to invite citizen participation in city government… celebrate the magnificence of our natural beauty…, incorporate public art…[be] a model for sustainable design and…serve the city for the next 100 years” [6]. The Seattle City Hall is one of five new or renovated buildings that form the Seattle Civic Center. It is a light and open structure with views to city, Puget Sound, and the Olympic Mountains. (It replaced the 1950s City Hall building that was characterized by small, dark, and cluttered spaces). BCJ describes the final building scheme as “a seven-story glass office block, a metal Council Chamber, and a lobby of transparent and translucent glass uniting the two. This transparency reflects the goal of an open, accessible city government, easily identified, where ordinary citizens can locate city services. The curved metal volume of the City Council Chamber is a modern form that evokes a civic dome.” [4].
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Public access
4.1 London “The ramps were conceived so that the public could see democracy in action by looking down at assemblies in progress. But in practice, when the assembly chamber is in use, people are barred from using the spiral ramps or even opening or shutting doors leading on to them because of the distracting noise.” [21]. Furthermore, except for occasional weekends, the general public is not welcome to the upper floors and when invited is subject to a security check. The lobby and lower floor are publicly accessible. The building is surrounded by public outdoor spaces that are paved in charcoal-gray limestone, exploit the riverbank site, and project a suitably civic character. On the west side lies a shallow amphitheatre, or “Scoop”, which can be reached from both the riverside walk above and the basement restaurant below. Tourists and local office workers find it an inviting bowl in which to take a break. Free musical events at lunchtime and dramatic performances in the evening are regularly staged for audiences of up to 1000 people. The Scoop is bounded on two sides by an external exhibition area and a model of the world. While the river walk and amphitheater are successful, the site’s large lawns are not inviting nor up to London’s expectations for parks [21]. 4.2 Seattle The Seattle City Hall was designed to be barrier free, and also includes a number of spaces designed specifically for social interaction and “community building.” [6]. The Grand Stairs provide seating as well as access to the Plaza and City Council chambers. City Council meetings can be televised to visitors in the lobby, and a fireplace and piano are also tucked away in a niche adjacent to a large meeting room. The lobby is large and open, providing visual and physical connections throughout the building, and the mayor’s office on the top floor is open to all comers. Public art is also highlighted in four installations at the lobby level. There are no security checkpoints in the building, so it is fully accessible to the public. The recently completed Fourth Avenue Plaza on the site’s southwest corner, together with the Grand Stair and Lobby provide a link and rest stop for people moving up the steep hill climb between a major public transit stop and the civic center. Like London, Seattle values its public parks and urban spaces, but the new Plaza has been criticized as a missed opportunity to be “a dramatic, all-things-to-all-people plaza that’s equally suited to private contemplation or noisy demonstrations.” [16].
5
Sustainable design strategies
5.1 London The design team’s intention was to cut energy consumption by a novel combination of architectural form and natural energy sources. Although the WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
138 Eco-Architecture: Harmonisation between Architecture and Nature building’s efficient spherical shape reduces the external envelope by 25%, it was originally conceived to be all glass, the most thermally permeable material. Arup’s solar studies convinced the architect to reduce the glazing to 25% of the façade of the east, south, and west-facing office floors. The remaining 75% is made of insulating panels with a glazed exterior face [2]. The shifted floor plates that form south-facing overhangs to cut solar gain in summer are less than moderately effective. The building’s more effective shading devices are the usercontrolled louvers housed between the panes of double glazing. The environmental system combines displacement and natural ventilation and perimeter heating. Cooling is provided by chilled beams that avoid conventional refrigerants and instead draw naturally cool water from two 50 m deep boreholes, which also greatly reduces electrical consumption and avoids CO2 emissions. It uses a quarter of the power needed for a conventional airconditioning system. The expended borehole water is used for flushing toilets and grounds irrigation purposes and excess is discharged into the Thames. In the GLA’s hybrid natural ventilation and air-conditioning scheme, the occupants can open the windows, to enjoy fresh air, providing them with some control over their environment. Opening the windows switches off the local air-conditioning, saving energy. On the fully glazed north façade, which affords spectacular views of the London skyline from the council chamber and the ramp above, cooling and heating are provided by cool ground water or heated water passing through the 300 mm diameter core of the horizontal primary steelwork of the structural diagrid, which becomes a series of giant tubular radiators. In the winter, some warmth is provided by recycling heat from people and office equipment. Air extracted from the offices passes through a heat exchanger that heats the incoming fresh air, supplied to the offices via a floor plenum at a low velocity to minimize the energy needed to power the fans. A gas boiler provides additional heat when required through trench heaters around the building’s perimeter [2, 9]. The curved office façade with user-controlled louvers puts all the workers close to apertures they can control for light and glare. The success of this daylighting strategy is highlighted by the occupants’ complaints about the contrasting, gloomy, un-daylighted committee rooms in the basement. Green transportation is encouraged by the site design. No apparent car parking is provided near the building (it’s under the green roof of the south lawn) nor do any roadways approach the building. The most obvious and attractive approach to the building is via the Thames-side walk. In 2005 “GLA facilities management received a £270,000 grant from the DTI to go ahead with the £500,000 scheme, which will convert light energy into electricity using the curved roof. Allan Jones, chief development officer for the London Climate Change Agency, which helps the mayor reduce carbon emissions in the city, said City Hall was built with the intention of installing photovoltaic panels at a later date.” [12]. These roof-mounted photovoltaics should generate up to 81 kW.
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5.2 Seattle The goals for sustainable design at the City Hall include providing connection to the outdoors, conserving energy and water, the use of sustainable materials, providing healthy indoor spaces, minimizing traditional effects of new buildings in an existing urban structure, “long-life, loose-fit,” and “smart mobility” [6]. More specifically, strategies include extensive use of natural light. Each façade is designed based on solar orientation and microclimatic factors. The north façade is fully glazed with translucent vertical fins that provide shade during the six month period it is exposed to direct sun. The lower council chamber’s south façade has wide horizontal louvers while the tower is shaded by a curving wall of fritted glass. The primary circulation space for each floor flanks the façade, providing public views to the green roof below while providing a buffer against solar gain. The west façade is protected by operable interior shading devices, and the east side which is shaded by the adjacent justice center features smaller punched openings. Small floorplates mean that most workers are able to sit close to a window. Strategies used to conserve energy include high efficiency HVAC equipment and a raised-floor displacement ventilation system. Electrical loads are minimized as a result of the design of the façade to optimize daylighting and reduce requirements for electrical lighting. Water conservation measures include waterless urinals, low flow lavatories and toilet fixtures. Rainwater run-off is collected in cisterns below the building, and used to water plantings and for toilet flushing. In addition, a large green roof detains rainwater during winter, reducing stormwater discharge, but also thrives without water during the dry summer months. Many of the materials came from local or regional sources and include recycled content. There has been some controversy; however, about the contra-sustainable use of titanium to clad the city council chambers (in an effort to pay homage to Boeing), and imported limestone cladding. In keeping with the concept of smart mobility, there is no public parking available on site; however, there are multiple connections to public transit and accommodations for pedestrian access.
6
Building performance
To assess building performance we have had to rely on evaluation by interested third parties—Building magazine [12, 21] for the GLA building and the Seattle Post-Intelligencer [13, 14] for the SCH. Meanwhile, in the UK after it comes in force on 6 April 2006 the Energy Performance of Buildings Directive will oblige public authorities to publish energy consumption data; and in Seattle an extensive post occupancy evaluation, now underway, will assess 20 environmental, social and economic indicators, providing a very broad view of City Hall’s performance. 6.1 London “City Hall does not meet its target of using one quarter of the energy for airconditioning required by comparable office buildings. Last year, it came in at 8% WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
140 Eco-Architecture: Harmonisation between Architecture and Nature above the government’s good practice guide for total energy usage, partly because the building is used more intensively than originally intended. (In the first three years of its life, the number of building occupants has grown to 650, well above the 426 for which it was designed) Even so, it still undercuts a similar prestige office building by 34%, and it exploits the renewable energy sources of ground water for cooling, and in the near future, photovoltaic cells for electricity.” [21]. The total energy in gas and electricity consumed during the financial year 2004/5 was 376 kWh/m2 of environmentally controlled floor area—50% above the energy consumption target of 250 kWh/m2 set at the design stage [21]. “City Hall is one of a number of high profile green buildings that have struggled to live up to their green credentials. Foster’s Swiss Re and Hopkins’ Portcullis House have also been found to perform better on paper than in practice. This discrepancy has been blamed on building managers, who critics say have yet to come to grips with how to run low-energy buildings. Energy experts at BRE blame a lack of communication between architects and facilities management for the shortfall in performance. A GLA spokesman said the building was using more energy for two reasons—first because it housed more people than it was designed to do and, second, because it was also used as a conference centre and tourist attraction.” [12]. 6.2 Seattle The Seattle City Hall was designed to achieve LEED silver certification, but after the building was completed and documented, it was found to have gained the higher rating of LEED gold even though photovoltaics, that were an original part of the design, have yet to be installed. However, the Seattle PostIntelligencer proclaimed “Seattle’s new City Hall is an energy hog” in the July 5, 2005 issue [13]. The article claimed, based on data provided by the local utility, that energy costs for operating the building ranged from “15% to 50% higher than for the older building that was replaced.” Closer review of the data indicates the new City Hall had lower overall electrical costs between May and mid-July, but was otherwise much more expensive to operate, especially in winter and spring. There has been much speculation about the causes of this situation—the building managers haven’t figured out how to run the system, there are many high ceilings and open spaces that must be heated in winter, and there are fewer occupants per square foot in the new city hall than in the old.
7
Conclusion
By examining these two buildings we’ve observed that even though the national political context (Kyoto and not) and architectural expression (internationalism vs. regionalism) contrasted, the strategies to attain sustainability are quite similar—a combination of low-tech strategies and advanced HVAC systems, attention to shading, incorporating daylighting, encouraging public use, and discouraging automobile access. Both buildings were initially praised for their ambitious green agendas. However, choosing to create an icon of sustainable WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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design attracted critical attention. After the initial honeymoon of public praise both buildings have encountered criticism for not truly attaining their lofty goals and both are undergoing assessment and evaluation for self-improvement. Should we be dismayed by this fall from public grace? No, not only do the two City Halls serve as exemplars of sustainability, but through public scrutiny, they also provide a template for a process that truly defines sustainable building. Sustainable buildings must be designed to be sustainable, must be commissioned to ensure that design intentions were met by the systems and features installed, must be assessed for fitness after they have be occupied for a year or two, and must be periodically re-evaluated. Both of these buildings have suffered “successful building” syndrome—their popularity and quality has attracted wider use than anticipated. So far design teams are fairly good at the design and improving on commissioning activities, but tend to walk away from the building after it’s completed, ignoring the lessons that could be learned from its occupancy. It is clear that when people occupy buildings they change the buildings’ behaviour and much of the criticism that both City Halls have encountered is as a result of their evolving patterns of use. Occupancy is not a predictable or constant state but changes continually over time, suggesting that a feedback loop is needed to determine the effects of occupancy on building performance (and coincidentally occupant performance). This evaluation can be accomplished by periodically assessing their performance as the building ages and each time occupancy patterns are significantly altered in order to adjust their operations and remodel their systems and features in response. The lessons learned from these assessments can also be used to improve future architectural and systems design. This system of stewardship and learning is the hallmark of long-term sustainability and is necessary to propel us into a future where the earth’s resources are not only sustained but regenerated, ensuring a joyful existence for future generations.
References [1] [2] [3] [4] [5] [6] [7] [8] [9] [10]
Arup, Designing City Hall, self-published brochure. Barker, Don, “Foster’s New City Hall.” Architecture Week, 26 March 2003. Bassetti Architects web page, www.bassettiarch.com. Bohlin Cywinski Jackson web page, www.bcj.com. Better Bricks, “Seattle City Hall Case Study” Northwest Energy Efficiency Alliance, www.betterbricks.com. City of Seattle, “Seattle City Hall” Brochure, 2003. City of Seattle, Seattle Municipal Civic Center Master Plan, June, 1999. GLA web site, “A Sustainable Development Framework for London,” www.london.gov.uk. Lane, Thomas, “Keeping Ken cool,” Building, October 12, 2001. Merkel, Jayne, “City Hall, London, England,” Architectural Record, 02 2003.
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142 Eco-Architecture: Harmonisation between Architecture and Nature [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22]
Miller, Brian, “Best Municipal Makeover,” Seattle Weekly, August 4, 2004. Miller, Vikki, “City Hall to add solar panels to boost green performance,” Building, September 16, 2005 Mulady, Kathy, “Seattle’s new City Hall is an energy hog,” Seattle Post Intelligencer, July 5, 2005. Mulady, Kathy, “Energy audit of Seattle City Hall sought,” Seattle Post Intelligencer, August 2, 2005. Office of Mayor Greg Nickels, “Mayor calls for Seattle, other cities to meet protocol goals” News Advisory, February 16, 2005. Olsen, Sheri, “On Architecture: Confusion trumps beauty at Seattle’s new City Hall”. Seattle Post Intelligencer, September 8, 2003. Paladino & Company, Inc. LEED Performance Evaluation Plan: Seattle Justice Center and City Hall, December 31, 2003. Pearson, Andy, “It’s a wrap,” Building, September 21, 2001. Seattle City Light, “City Hall Energy Usage” table published in Seattle Post-Intelligencer, July, 2005. Shogren, Elizabeth, “Seattle Tackles Greenhouse Gases” NPR Morning Edition, November 28, 2005. Spring, Martin, “Time has told,” Building, October 21, 2005. Steinbrueck, Peter, in an interview entitled “City Hall and the Legacy of New Public Architecture”, Arcade Magazine 22.2, March 2003.
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Poetic water images in architecture U. Kirschner Department of Cultural Studies, Lüneburg University, Germany
Abstract This essay identifies and examines uses of water imagery in architecture worldwide and through centuries. Architects have introduced imagery in their architectural design since antiquity. This analysis illuminates how the intensive interaction with nature, in this case with water, corresponds to an ever lasting spirit. As Thales of Milet declared: “Water is the source of all things” [1]. This element plays a unique role in the interaction of natural forces. During the Renaissance and particularly during the Baroque age resistance to social alienation was expressed in an abundance of ornamentation; the water foliage and wave formations on the colonnaded capital are analogous to the multitude of water images at times used extensively in lyricism. The water with its varying states of aggregation and mobility inspired many architects to spectacular designs. Keywords: design method, analogies in architecture, nature and architecture.
1
Introduction
In all cultures, rituals and symbolism are influenced by the evidence and unlimited abundance of the “element” water. “Water escapes the earth’s surface in the form of a spring, moves forward as a river, stands still as a lake and rests in eternal calmness, yet everlasting movement in the form of the ocean. It transforms itself to ice or to steam, it ascends through evaporation while it descends as rain, snow or hail ... it hovers as a cloud ... it is colourless, yet can take on all colours ... it is formless, yet can adapt to any given form; it is soft, yet stronger than stone. It creates contours in the form of valleys, coastlines and grottos” [2]. In mythology and legends, the oceans and rivers are inhabited by gods and goddesses, spring and water nymphs, sirens and mermaids. The water source, the spring, symbolizes the tears, blood and milk of Mother Earth. In the
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144 Eco-Architecture: Harmonisation between Architecture and Nature atmospheric lyricism of the 18th century, metaphors such as mentioned were often portrayed. Poets employ water as a metaphor for abundance and power, strength and movement, temptation and danger; an idyllic, on the other hand, uses water colour to create a peaceful and balanced atmosphere. According to Goethe “Poetry reveals the mysteries of nature and attempts to solve these mysteries through imagery” [3]. Water is one of the most archetypal images with which poetry attempts to do this [4].
2
The influence of water on space
“When water comes in contend with solid elements, is when it becomes imaginative. It creates forms, whirl pools and veils, drops and streams, rivulets and veins around every stone it comes in contact with. It endlessly swirls about the solid element, nestles itself up to it and hollows out a space within it” [5]. In the Wells cathedral the nave is connected to the main hall of the clerical chapter by a waterway, which divides itself into two different levels. This English church is otherwise designed according to rules of Gothic tradition with the influence of Roman cubes and Gothic curves. The attributed bold entryway has been guiding the course of a multitude of clerics for centuries. The hand-modelled stairway, constructed according to the architectural prerequisites, subtly bridges the altitude difference of the nave level and the foyer level, fig. 1. Its function as an entryway into the chapter hall seems secondary to the beautiful image of flowing water that it creates.”
Figure 1:
Cathedral of Wells [6].
Water appears to have left its footprints in the form of a hollow in the middle of each step. This illusion gives the steps of Wells a flowing rhythm, like that of waves [7]; their beauty lies in their resemblance to the natural movement of the water. An increase in kinetic energy creates vibrations on the waters’ surface. Waves are the result of the complex dance between water, wind and time. Antoni Gaudi built a school on the Sagrada Familia plot in Barcelona based on the idea of using stone to create wave sequences. Gaudi’s choice of the wave as the main motif of his design was religiously inspired; it is a temporary apparition. Additionally, the wave offers practical construction advantages: the curved structure increases the weight-bearing capacity of the facade as well as the WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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ceiling, which was built in the form of the sine curve, fig. 2.1. Thus, it was completely unnecessary to use any pillars or structural bearing walls in the interior space. The exterior is constructed in highly porous brick, suitable to the weather in northern Spain.
Figure 2:
1. School in Sacrada Familia, Gaudi, 2. Opera, Philippines, Locsin [8].
In contrast to Gaudi’s romantic portrayal of waves, the Philippine architect Leandro of Locsin designed the Theatre of Mount Makiling in Los Banos (1976), as a possible precursor for a storm tide of Homeric dimensions: “Like the storm of relentless wind.. ./. . .excites the flood and creates the breaking waves of the thunderous open sea...” [9]. As an architect, Locsin worked with similar expressiveness as Homer on the design of the theatre and opera house in which he had previously worked as singer and stage designer [10]. For this building, he chose the form of a threatening, somersaulting wave complemented by its mirror image in a flat pool of water, situated in front of the building, fig. 2.2. The inherent strength of the construction resembles a dancer, who requires every muscle in order to float as light as a feather across the stage. Time frozen in an image is the major factor characterizing these artistic portrayals. Time is frozen in the form of an edifice.
3
Water mythology – fantasies of space
A mirrored water image creates the centre of the 17th century Schah mosque in Isfahan. The mosque courtyard is laid out in the shape of cross. Four liwane or arched entryways symbolically support the canopy of heaven above the indoor courtyard and border the pool in its centre, fig. 3.1. The water mirrors the surrounding edifices and vaults. The mirror image reconstructs both the horizontal and vertical axes of the edifice, while at the same time creating a third vertical axis, connecting water, heaven and earth. The nature of the orthogonal grounds keeps the visitor on the centre line. The central entrances through the liwane into the courtyard lead the visitor to the focal point of a “kaleidoscopic vision”, which reveals the infinity of creation [11]. Many languages use only one word for the terms: soul, image and shadow. An image is considered to be a
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146 Eco-Architecture: Harmonisation between Architecture and Nature living representation and embodies the soul of its bearer. Much more value is attached to it than to the human body itself [12].
Figure 3:
1 Isfahan, Liwane;
2. Insurance Building, Ipswich, Forster [13].
“Narkissos fell in love with his own mirror image while drinking water from a spring. Because he could not attain this image, he was devoured by desire and transformed into a flower, the narcissus” [14]. In contrast to this well-known metamorphosis water can also provide a living dimension to lifeless matter, for example a building. Norman Forster chose, consciously or unconsciously, the smooth surface of pond water, as his design motif for the Willis Insurance Building in Ipswich, 1974, fig. 3.2. The amorphous floor plan is reminiscent of a lake that one can only walk around and can only set foot upon when frozen; the building is circumnavigated by traffic as if it were an island. The facade of the building is a mirror image of the surrounding city life, creating a magical point of attraction. Much like the mirroring waters of a garden, it seems to be the eye of the city.
Figure 4:
Admission Building, India, Correa [15].
From 1967-1972, Charles M. Correa built the administration building for the Electronic Corporation of India in Hyderabad, fig. 4. His idea was to create a sober and demystifying replication of the sea. Correa analyzed the ecological conditions in the depths of the sea and put his findings to work by creating an office building with optimal climatic conditions. The shape of the roof is amorphous, similar to Forster’s floor plan. Individual, crystalline-shaped threedimensional spaces are situated just under the roof. For cooling purposes, pools of water were installed above these closed spaces. These pools reflect sunrays, intensifying the comparison to a stilted sea surface with a rocky reef shimmering below. The rest of the roof consists mostly of segment bars, which partly cover WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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the courtyard and partly jut out, partially shading the underlying rooms. The interesting dance between light and shadows suggests the atmosphere of the underwater world. With these and other simple methods, Correa created the prerequisites for a salubrious climate without using any energy-wasting facilities.
4
Ice-, snow- and fog-architecture
Water exists in fluid form, in solid form or as steam. Under normal pressure conditions, at 100°Celsius water transforms into steam, at O°Celsius it freezes, and at 4°Celsius it possesses the highest density. Ice is water in its partcrystalline, part-solid aggregate state. Unlike ice, snow is not frozen fluid but rather water, crystallized through condensation. Water differs from most substances in that the transformation from the fluid to the solid state involves a reduction of density. The result of this is that ice floats on water, but it can also display explosive force when it is generated from water.
Figure 5:
1. Im Eismeer, C.D. Friedrich; 2. Opera, Skopje, Tange [16].
A well-known ice motif is Le Corbusier’s chapel roof of Ronchamp, modelled in the form of a voluminous, one-meter-thick snowdrift. Caspar David Friedrichs’ famous painting “In a sea of ice”, fig. 5.1, with its steeply erected, overlapping ice floes, served as the main atmospheric inspiration for Hamburg’s utopian cities, designed by students of various universities, among others [17]. Deconstructivists, in particular, especially like to implement this repertoire of forms. The Slovenian architecture group “Studio 7” constructed such a work of art in an Opera house in Skopje, located in the southern province of Macedonian, fig. 5.2. Following an earthquake that destroyed the city, Kenzo Tange worked out a concept for the restoration of the city in 1968. He situated the new opera house adjacent to the Vardar River, directly in the centre of the city. The opera house was built from 1972-1981 and is considered one of the most important post-war constructions of the country [18]. The architectural team described the edifice as follows: “Motion and vitality have been created by the purity of form and diversity of space reaching from the interiors to the exteriors. The play of light and shadows on the white walls additionally enhances the idea and expression of the space” [19]. In their design of the opera house, the architects adopted the tangible drama of Friedrich’s painting, with its virtual cracking and breaking sounds of shattering ice floes, and accentuated it with white colour. In
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148 Eco-Architecture: Harmonisation between Architecture and Nature the preceding examples, we have considered the forms that water can create as well as interpreted the movement and various states of water. Glass is a building material which is similar to water and ice in many ways. The physical correlation between glass and water lies in the fact that glass is solidified fluid.
Figure 6:
Kirchner Museum, Davos, Gigon and Guyer [20].
The entire facade of the Kirchner museum building complex in Davos, Graubünden (Northern Switzerland) is seemingly constructed entirely of glass and gives the impression of water in its aggregate states, fig. 6. The Zurich architects, Anette Gigon and Mike Guyer, erected the museum in 1992, which is comprised of four massive cubicles, the exhibition rooms and the entry hall. All constructional components, with exception to the entryways, are panelled with matted, i.e. cauterized glass plating. The fibrous surface structure of the insulation material shimmers through the glass plating, leaving the impression of a glittering, non-transparent ice surface. With its diffuse reflections, the house seems to adapt to the seasons like a chameleon. It is as if the building puts on a cape of fog when the mountain summits are buried in the clouds; when the landscape is covered in snow, the glass front shimmers in a light shade of green, like glacier ice; the glass cubicles glimmer in the falling rays of sunlight. The roof of the museum with its diffuse reflecting glass-splinter surface, complements the building facade. Despite the amount of glass incorporated into its facade, the building offers only a minimal view from the outside into its interiors; similarly, from the inside, one can see only little of the surrounding high mountain landscape. The exhibition rooms exclude the outside world. Only three-meter-high small, angled ceiling windows provide indirect light exposure, allowing the daylight to stream in at a side angle. Traditional ceiling windows are too readily darkened by falling snow. The raw concrete walls of the connecting hall correlate to the outside world. Correspondingly, the sculptures are intentionally situated to seemingly be a part of the surrounding mountain landscape [21].
5
The relationship between water and location in architecture
Since primeval time man has dreamed of controlling the forces of nature. C. N. Ledoux designed a home for the Director of the Department of Water Control in the form of a pipe connected to a massive underground foundation, WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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fig. 7.1. Retained by the pipe walls, the wild mountain water of the Loue River rushes through the house. This design was never built and was often criticized because it did not meet the prerequisites of a residential home. Nevertheless, it was a project that fully incorporated the force of water and the spectacular image is still frequently referred to today.
Figure 7:
1. Livinghouse, F. L. Wright [22].
Ledoux;
2. and 3. Fallingwater
house,
The “Falling Water” house from Frank Lloyd Wright is the perfect example of a man-made imitation of the phenomena of water and nature. Wright built this vacation home above a waterfall, a constant cascade of falling and flowing water over massive rock formations ending in the Ohiopyle Valley below. Using glass and concrete, he seemingly extended the waterfall in an upward direction, fig. 7.3. From the foot of the waterfall by day, the whitewashed basins seem more like falling water and the dark glass components look like water-covered stones. At night, the opposite effect occurs. The reflection of artificial lighting makes the glass seem bright and pattering, while the basin edges disappear in the darkness. In the winter, the terraces lose their gleam next to the snow-covered stone landscape and now-frozen water. In the winter months, not only the visual impression but also the functionality of the house is reduced to its stone towers and glass volumes. This project was constructed using only horizontal surfaces, i.e. the surface of water, and perpendicular lines, i.e. falling masses of water. Wright avoided the use of diagonals where possible; not even one handrail or banister exists in the entire house. The stairways are suspended from vertical poles or built between two parallel walls, fig. 7.2 [23]. My personal choice for the theme of an architectural project was the encounter between water and stone. On the northern island of Germany called Helgoland, the ocean is the dominant force versus the red sandstone cliffs. A boarding school for children suffering from allergies was to be built on a strip of man-made land between the northern jetty and the edge of the cliffs. The exposed setting and the unique location of the windy island offered the perfect architectural stage. The complex is composed of five residential houses, a combined school building and sports hall, as well as a stone garden and an underwater garden. The architecture and layout of the complex reflects the emergence of Helgoland, fig. 8. Through a crack in the stratum layers, water poured into the salt masses lying deep below the surface. Over time, the osmotic pressure pushed the new red sandstone layers from southwest to northeast. At the WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
150 Eco-Architecture: Harmonisation between Architecture and Nature 27° angle of inclination found today, the move stopped as the water had become saturated with the accumulated salt masses [24]. In the design the stone garden is a ground relief created by the exposed stratum layers. Within the five boarding houses, the rock layers form a great mass, raising up the oceans here in the form of a skin of glass and opening the gate to the underwater world. The “underwater garden” is also used by a neighbouring biology institution. With its aquariums, it serves as a space for experiments and exhibitions, illuminated by the light shining through the skin of glass above it. This “skin of glass” also serves as the floor for observers to walk on as they steal a view into the underwater world. The boarding school children have access to this virtually allergy-free world through the connecting multi-purpose rooms of the residential building. The garden serves as an entryway to the joint boarding school and sports hall. It is as though this building were a cascade on the mountainside making the stratification and crystalline quality visible. The boarding school is built as a stilted terrace above the sports hall with a splendid view of the ocean beyond the roofs of the boarding houses. The school courtyard is situated on the roof of the sport hall and bordered by carefully placed flood lights.
Figure 8:
6
Design for a boarding school, Helgoland, Kirschner, photo of the cliff.
Conclusion
Metaphors, which act as ideas for architectural designs are analysed in this paper. In nearly the same way as styles pictures can act as leitmotif, their perception touches the depths before moving the surface [25]. Architecture ought to address more than functional constraints; and instead engage in and adapt an interactive exchange with other arts and issues. While painting, sculpture and literature may depict – but do not really have to – architecture, like music, has to create its own topics. This is the principle task of architectural design. Here in particular the element of water with its figurative polarity may serve as a metaphor for mythic death as tide and at the same time as the source of life itself. The church like a ship with Christ as its captain on the rough sea is an essential Christian image. In the use of religious symbols in sacred buildings or the representation of operational sequences in functional buildings their design idea becomes obvious. This holistic approach is described by Walter Benjamin this way: “Humans have a primal urge, to correlate the objects and phenomena of their world” [26]. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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References [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25]
Thales-Zitat 6. Jh. v. u. Z., ed. Böhme Hartmut Kulturgeschichte des Wassers, Frankfurt a. M. pp. 52-53, 1988, Böhme Hartmut (eds). Kulturgeschichte des Wassers, Frankfurt a. M., pp. 12-13, 1988 Trunz v. E. (eds). Maximen und Reflektionen, No. 904, Goethes Werke, Hamburg 1948, XII, 493. Blume Bernhard, Existenz und Dichtung, Frankfurt a. M., p. 152, 1980 Schwarz Rudolf, Von der Bebauung der Erde, Heidelberg, p. 53, 1949 Peter Sager, DuMont Kunst-Reiseführer Südengland Köln p. 227, 1989 Sager Peter, DuMont Kunst-Reiseführer Südengland, Köln, pp. 251-252, 1989 2.1. Zerbst Rainer, Antoni Gaudi, Köln, p. 214, 1987; 2.2. Polites Nicholas, The architecture of Leondro V. Locsin, New York + Tokyo S 108, 1977 Homer, “Ilias”, in Bernhard Blume (eds), Existenz und Dichtung, Frankfurt a. M., p. 150, 1980 Udo Kultermann, Architekten der Dritten Welt, Köln, p. 157-158, 1980 Henry Stierlin, Isfahan, Orbis Terranun, Genf, pp. 78-83, 1976 Martin Ninck, Die Bedeutung des Wassers im Kult und Leben der Alten, Darmstadt, p. 58, 1960 3.1. Stierlin Henri, Isfaha, Genf, pp. 112, 83, 1976; 3.2. ChaslinFrancois, Hervet Frédérique, Lavolou Ammolle, Norman Forster, Paris, pp. 56-57, 1986 Ovid, Metamorphosen 3, Frankfurt a. M. 1998. Cantacuzino Sherban, Charles Correa, Singapore, pp. 36-37, 1984 5.1. Friedrich C. D., Im Eismeer, www.Onlinekunst.de/september/05_ eismeer _friedrich.jpg; 5.2. Kultermann Udo, Zeitgenössische Architektur in Osteuropa, Köln, p. 198, 1985 Held-Schäfer Andrea, in Bauwelt 40/1987, Dissertation, Gütersloh, pp. 1508-1509 Kultermann Udo: Zeitgenössische Architektur in Osteuropa, Köln, pp. 197-198, 1985 Udo Kultermann: Zeitgenössische Architektur in Osteuropa, Köln, p. 200. 1985 Kirschner Ursula, 2002; Binder Hans, db, Stuttgart, pp. 64, 4, 8/1994 Binder Hans, db, Stuttgart, pp. 64-69, 8/1994 7.1. Vidler Anthony, Claude-Nicolas Ledoux, Massachsetts, p. 320, 1990; 7.2., 7.3. Hoffmann Donald: Frank Lloyd Wright´s Fallingwater, New York, p. 94, 1978 Hoffmann Donald: Frank Lloyd Wright´s Fallingwater, New York, p. 59, 1978 Geologisches Jahrbuch, Reihe A, Heft 62 Barchelard Gaston, Poetik des Raumes, München, p. 17, 1975
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152 Eco-Architecture: Harmonisation between Architecture and Nature [26]
Benjamin Walter, Die Lehre vom Ähnlichen, in: Siegfried Unseld, Zur Aktualität Benjamins, Frankfurt a. Main, p. 23, 1972
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Section 3 Design with nature
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The 2005 Solar D house M. Garrison School of Architecture, The University of Texas at Austin, USA
Abstract The Solar Decathlon provided an international forum for competition among eighteen university student teams, each of which designed, built, and operated a totally solar-powered home with a home office and their transportation needs using a solar-charged vehicle. Organized by the U.S. Department of Energy and the National Renewable Energy Laboratory, the Solar Decathlon competition challenges university teams to design and build an 800 ft2 (74.3 m2), totally solar-powered house. The competition took place on the National Mall in Washington D.C., where each house was constructed and operated from September 28 to October 19, 2005. The competition consisted of ten contests focusing on ingenuity, energy production, energy-efficiency, design, thermal comfort, refrigeration, lighting, communication and transportation. Professor Michael Garrison, Assistant Professor Samantha Randall and Lecturer Elizabeth Alford of the School of Architecture were the faculty advisors for the University of Texas at Austin (UT) Solar Decathlon student team, which included more than 40 graduate and undergraduate architecture, landscape architecture, and engineering students. The team developed a design that features four pre-fabricated modules that can be snapped together in order for the house to be transported from Austin, Texas to Washington D.C. and constructed in just four days, operated for two weeks, and then deconstructed and sent back to Austin, Texas again. An innovative foundation system of rails and rollers allow each module to be lowered off a truck and rolled onto the rails and the fours sections of the house snapped into place.
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Design
The University of Texas 2005 Solar Decathlon House is limited in size by rules of the competition, which, require that the roof “foot-print” must be less than WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060161
156 Eco-Architecture: Harmonisation between Architecture and Nature 800 ft2. To provide our modest 1-bedroom/1 bath house with a spacious feel, the team utilized three design techniques. 1) The spaces are multi-use, so the bathroom is also the laundry room; the bedroom has a foldaway bed so it can function as an office/study during the day; and a central main room contains the kitchen, dining and living room in an open plan configuration. 2) The main room connects to a patio deck space along the entire south elevation to expand the interior space to the outdoor deck space. 3) The combination of a cathedral ceiling and generous amounts of daylighting enhance the sense of spaciousness in the modest sized house.
Figure 1:
2005 UT Solar D house on the National Mall in Washington D.C.
Figure 2:
UT Solar D house south elevation.
The design of the house stressed four fundamental principles including, 1. Well constructed and tightly sealed thermal envelope with appropriate ventilation. 2. Proper design and installation of heating and cooling systems (properly sized, high-efficiency, good ventilation and sealed ductwork). 3. Energy-efficient doors, windows, and appliances. 4. Home orientation and placement of building elements to maximize natural heating and cooling efficiency. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Figure 3:
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Interior of the UT Solar D house with Congressman Lamar Smith.
Energy systems
The Texas solar decathlon house is solar-powered and utilizes the latest energy efficiency technologies and sustainable building materials. The Energy saving features of the house include, a 7.9 kW photovoltaic solar power system, evacuated tube “heat pipe” solar water collectors, a high efficient HVAC system and an energy conserving design that achieves a ratio of one ton of air conditioning per 933 ft2 (86.7 m2) of conditioned space. The HVAC system combines a variable-speed Inverter compressor mini-split heat pump with an energy recovery ventilator, a separate refrigeration whole-home dehumidifier and horizontal direct-drive chilled water DHW/Air Coil heat exchanger. The four components work together to assure a narrow interior comfort zone of between 72˚F and 76˚F (22˚C and 24.4˚C) and a humidity range of between 45 and 50% relative humidity. To control the components the team developed a computer controlled smart building technology that allows the building to be controlled on the Mall from Austin, Texas. 2.1 Photovoltaic solar system The Texas 2005 solar decathlon house is designed to be energy efficient and is a stand-alone system, which does not use electric utility power. PV’s provides direct DC power when sunlight is available. If power is needed when sunlight is not available, batteries will be required to store power for the times when the sun is not shining. The Texas 2005 solar decathlon house has 42-175 W BP polycrystalline panels and 4 Romag-BP custom-translucent thin film panels that comprise the 7.9 kW PV system. For our area, we multiplied the rated wattage by 5.1 to get the average Wh (watt hours) amount produced in one day. The 5.1 factor equals WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
158 Eco-Architecture: Harmonisation between Architecture and Nature the viable operating hours per day and accounts for the fact that there will be more sun available in the summer and less in the winter (7.9 kW x 5.1 = 40.29 Wh). The 42 BP 4175 modules are mounted on the roof canted at 20 degrees. The 4 BP-Romag custom modules are cantilevered off the roof, shading the southern glazing. Single insulated conductor MC USE-2 cables are used to connect the modules in free air to roof-mounted fuse/combiner boxes. The PV array is divided into three inverter groupings; 4 parallel/8 series BP 4175B modules for the SB6000U inverter and 10 series BP4175B modules for the SB2500U inverter. All series strings first go through fuses in pullout holders before any combing of parallel circuits through a terminal block. After the combiner boxes, conductors are run from the roof to the electrical closet. The electrical section of the closet contains the disconnect switch and over current devices for the PV array, the inverters, the DC circuit breakers, and the AC distribution panel. A contiguous, but separated section of the closet is used to store the 32-Marathon 12V batteries. The system is dependent on the inverters to perform all necessary ground fault detection and interruption (GFDI) of ungrounded and grounded conductors to prevent fire on the roof mounted system. Although the solar decathlon competition requires a stand-alone system for the competition on the National Mall, this system will be adapted to a grid connected system upon the redeployment of the house in Austin, Texas after the competition. In the grid connected system PV’s can, provide power directly to the user and to the centralized power grid when PV power exceeds the user’s requirements. The Austin solar decathlon house will use power from the central utility when needed and supplies surplus home-generated power back to the utility. It is termed a “parallel” system by Austin Energy. The power produced will be metered so that when power is produced by the PVs and sent into the grid the meter will run backwards, thus allowing for a discount in consumption costs. 2.1.1 Evacuated tube solar water heating The 2005 Texas solar decathlon house utilizes Sunda’s Seido evacuated tube solar water collectors, which function as heat pipes. A heat pipe acts like a lowresistance thermal conductor. Due to its thermal-physical properties, its heat transfer rate is a thousand’s times greater than that of the best solid heat conductor of the same dimensions. Sunda’s Seido heat pipe is a closed system comprised of two meters of copper tubing, an evaporator section, a capillary wick structure, a condenser section and a small amount of vaporizable fluid. The heat pipe employs an evaporating-condensing cycle. Heat pipes are inserted into the aluminum absorbers forming assemblies, which in turn are inserted into the glass tubes. The tubes are made of borosilicate glass, which is strong and has a high transmittance for solar irradiation. In order to reduce the convection heat lost, glass tubes are evacuated to vacuum pressure. By evacuating air out of the glass tube the absorber material and selective coating are protected from corrosion and other environmental influences.
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2.1.1.1 Energy conservation The 2005 Texas solar decathlon house utilized a number of energy conservation design standards to improve thermal performance, including site planning and building configuration, thermal capacitance; thermal insulation; glazing type, amount and orientation of windows and air flow. The UT solar decathlon house is elongated on an east-west axis which is the most efficient shape for most U.S. climates because it captures low-angled solar radiation in winter, which minimizes heating requirements and, with a properly designed shading overhang, minimizes cooling requirements in the summer. Because the diurnal temperature swing during the summer months in Washington D.C. and Austin, Texas is relatively low, the likelihood of inadequate night time flushing of a high thermal capacitance design led our team to a strategy of light frame construction. Light frame construction also allows the HVAC system to respond more adequately to a rapidly changing exterior climate. The next consideration is the type of wall, roof, and foundation system to be used and the R-value that will be achieved. R-value represents resistance to heat flow, the higher the R-value, the better a wall’s efficiency. High R-values can be achieved with any type of construction: standard “stick-built” or alternative wall construction methods such as structural insulated panels, insulating concrete forms, or straw bale construction. Our team chose to use 6-inch thick structural insulated panels, which are rated at R-30. Windows, which have a much smaller R-value than walls, can have a large impact on the energy efficiency of a building. For this reason, one step towards efficiency is to minimize window area, which for our building represents less than 13% of our wall area. There are several other factors to consider when choosing windows including, frame material, glass coatings (such as low-e), gasfill between the panes, overall U-value, solar heat gain coefficient (SHGC), and ultraviolet (UV) and visible light transmittance (VLT). Windows specified for the Texas Solar Decathlon House are Comfort Line fiberglass Low-E, argon filled. These windows have a typical U value of .24 and a SHGC value of .38. The fiberglass frames do not expand and contract with water or differences in temperature, they have a strong strength to weight ratio, do not degrade due to sunlight and contain a recycled glass content. Keeping air from leaking in and out of a building can dramatically reduce energy needs. Air infiltration, which occurs naturally through small gaps and cracks between a wall and foundation, around windows and doors, and through utility penetrations between conditioned and unconditioned spaces, can be a big source for energy loss. Air infiltration can draw in humidity during the cooling season, and create uncomfortable drafts during the heating season. To improve comfort and reduce energy use created by air infiltration, our team caulked and sealed all the air leaks of the house during the framing and finishing process of construction. Taken together the energy conservation techniques utilized in the UT solar decathlon house provided an energy efficient design with a ratio of 933 ft2 (86.7 m2) of space per ton of air conditioning. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Material systems
The UT Solar D Team has chosen to think beyond the competition requirements of solar power and energy efficiency by embracing the full spectrum of sustainable design. This strategy includes resource efficiency and the use of recyclable, recycled, reused, and local underutilized materials. Recyclable materials include the house’s exterior zinc siding, the galvalume roofing, the stainless steel trim and the structural steel foundation rails. Building materials made from recycled materials include, the exterior decking, which is made from recycled plastic and wood scrap, the bathroom tile, which is made from recycled class and granite scrap, the bathroom wall panels made of Ecoresin recycled plastic and the redwood trellis rain screen made from reclaimed redwood. Examples of reused materials include aluminum shingles, which are reused newspaper litho plates from our school newspaper the Daily Texan. Local and underutilized green materials are also used as well. These include the use of mesquite wood flooring, cabinets made from MDF agricultural waste straw fiber and trim made from local reclaimed cypress. In addition to using green materials to construct the house the team recycled all the jobsite construction wastes. Structural Insulated Panels (SIPs) are an innovative green-engineered material system used to construct the UT Solar D House. SIPs replace conventional stud or “stick frame” construction. They were made in a factory and shipped to our job site where they were connected together to frame the walls, floor and roof of the house. A SIP consists of an engineered sandwich or laminate with a solid expanded polystyrene foam core 6” thick and structural galvalume facing on each side. The facing is glued to the foam core and the panel is pressed in a vacuum to bond the sheathing and core together. SIPs structural characteristics are similar to a steel I-beam. The skins act like the flanges of an I-beam, and the rigid core provides the web of the I-beam configuration. This composite assembly yields stiffness, strength, and predictable performance
Figure 4:
Metals USA SIP wall and floor panels.
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The greatest advantage of these panels is that they provide superior and uniform insulation in comparison to more common methods of house construction. SIP walls are superior to conventional walls in a number of ways. SIPs combine a high insulation R-value with speed and ease of construction. The solid foam core eliminates air movement within the walls and minimizes thermal bridges through wood studs. Together, all these reduce air infiltration, and make a tightly sealed/easy to build structure. This makes the building more comfortable, energy-efficient, and quieter.
Figure 5:
Metals USA SIP panels.
In regard to Fire safety, SIPs have performed well in combustion tests. When the interior of the SIP is covered with a fire-rated material such as gypsum board, the fire resistance of gypsum board protects the SIP facing and foam long enough to give building occupants a good measure of escape time.
4
Process conclusions
To provide for a pedagogical method to link architectural theory to practice, the hands on experience of the solar decathlon gave architecture students proper grounding in action and immediate experience and argues in favor of experiential knowledge over ungrounded abstract knowledge. This experience allowed students to develop the knowledge of how to apply and test out their ideas and theories on sustainable design. This kind of knowledge is rooted in the realms of value. And these kinds of values and consequences are acquired through the actual building experience. In this way the students are able to evaluate the performance of design decisions. Hands-on learning seeks to re-establish the continuity and inter-relationship between the processes of conceiving, making, and using buildings. In architect Samuel Mockbee’s words, “its the importance of making and thinking at the same time.” The “hands-on” process fosters a pedagogical approach that encourages faculty and students to discover how buildings really work as they are constructed and occupied. Through observation, simulation, and data gained by WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
162 Eco-Architecture: Harmonisation between Architecture and Nature designing and then building the design, students discover lessons on the success and failure of different design approaches. Analysis of the material observed in the field, along with comparisons to values derived by model studies, computer simulation and calculations, gives students an opportunity to assess whether the stated design intent has been achieved and to understand and describe the variety of ways occupants actually experience a building. This level of understanding involves both disciplinary and interdisciplinary learning. It is this area that the solar decathlon experience is especially potent as the forum in which disciplinary knowledge and interdisciplinary understanding take place.
References [1] [2] [3] [4]
[5]
Rating System For Pilot Demonstration of LEED ® for Homes Program US Green Building Council, Washington D.C., 2004. NAHB Green Home Building Guidelines User Guide NAHB MODEL GREEN HOME BUILDING GUIDELINES, Part Two, Washington D.C., 2005. Sustainable Building Sourcebook: by Austin Energy Green Building Program, Austin, Texas, 2003. Solar Decathlon 2002: The Event in Review, by Mark Eastment, Sheila Hayter, Ruby Nathan, Byran Stafford and Cecile Warner, National Renewable Energy Laboratory, U.S. Department of Energy, Washington, D.C. 2002. Building Envelope, by Randall Stout and Michael Garrison, National Council of Architectural Registration Boards, Washington D.C., 2004.
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Fractal geometry and architecture: some interesting connections N. Sala Accademia di Architettura, Università della Svizzera italiana, Mendrisio, Switzerland
Abstract Some man-made objects are geometrically simple in that they resemble idealized forms such as lines, planes, cubes, or polyhedra. Ever since Euclid invented geometry, people have been content with the idea that all objects can be classified as compositions of regular geometric shapes. The architecture found inspiration by the Euclidean geometry and by the properties of the symmetry. The analogy between natural and architectural forms sometimes catches us profound impressions. Some architectural styles, for example the Baroque, found inspiration in nature, and it is not possible to describe nature using simple lines and curves. Nature is manifestly irregular and fractal-like. So perhaps we should not be so surprised to find fractal components in architecture. As we shall demonstrate, fractal geometry appears in architecture because it permits one to reproduce the complex patterns and the irregular forms present in nature. The aim of this paper is to present a fractal analysis applied to different architectural styles. We shall also introduce the fractal geometry applied in the large scale, describing some examples in the African and in the Oriental settlement architecture. Keywords: fractals, architecture, self-similarity, urban organisation.
1
Introduction
In architecture it is usual to search the presence of geometrical and mathematical components. For example, the Euclidean geometry, the golden ratio, the Fibonacci’s sequence, and the symmetry [1–7]. We can also observe the architecture using a different point of view, for example to find some complex or
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164 Eco-Architecture: Harmonisation between Architecture and Nature fractal components that are present in the buildings or in the urban planning [8–11]. The fractal geometry appears in architecture because it helps to reproduce the forms present in nature. Our fractal analysis has been divided in two parts: • on a small scale analysis (e.g., to determine the fractal components in a building); • on a large scale analysis (e.g., to study the urban organisation). In the small scale analysis we observed: • the building's self-similarity (e.g., a building’s component which repeats itself in different scales), • the Iterative Function Systems, IFS, (e.g., iterative fractal processes present in architecture). In the large scale analysis we observed: • the self-similarity in the settlement architecture, • the fractal components present in the urban tissue. Fractal components are present in different Gothic buildings, for example in the “Fractal” Venice [12], in the Gothic Cathedrals, and in the Baroque Churches, for example in the church of San Carlo alle Quattro Fontane (Rome), conceived by the Swiss architect Francesco Borromini (1599-1667). In this paper we present our analysis applied to different architectural styles. We shall also introduce the fractal geometry applied in the large scale describing some examples present in African settlement architecture (e.g., Mokoulek, Cameroon) and in the Oriental settlement architecture (e.g., Borobudur, Indonesia).
2
Fractal geometry
Fractal geometry is one of the most exciting frontiers in the fusion between mathematics and information technology. A fractal could be defined as a rough or fragmented geometric shape that can be subdivided in parts, each of which is approximately a reduced-size copy of the whole. The term fractal was coined by the Polish-born French mathematician Benoit B. Mandelbrot (b. 1924) from the Latin verb frangere, “to break”, and from the related adjective fractus, “fragmented and irregular”. This term was created to differentiate pure geometric figures from other types of figures that defy such simple classification. The acceptance of the word “fractal” was dated in 1975. When Mandelbrot presented the list of publications between 1951 and 1975, date when the French version of his book was published. The people were surprised by the variety of the studied fields: noise on telephone lines, linguistics, cosmology, economy, games theory, turbulence. The multiplicity of the fields of application has played a central role to the diffusion of Mandelbrot’s discovery. Fractals are generally self-similar on multiple scales. So, all fractals have a built-in form of recursion. Sometimes the recursion is visible in how the fractal is constructed. For example, Cantor set, Sierpinski triangle, Koch snowflakes are generated using simple recursive rules.
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2.1 The self-similarity The self-similarity is a property by which an object contains smaller copies of itself at arbitrary scales. A fractal object is self-similar if it has undergone a transformation whereby the dimensions of the structure were all modified by the same scaling factor. The new shape may be smaller, larger, translated, and/or rotated. “Similar” means that the relative proportions of the shapes’ sides and internal angles remain the same. As described by Mandelbrot [13], this property is ubiquitous in the natural world [13]. Oppenheimer [14] used the term “fractal” exchanging it with self-similarity, and affirmed: “The geometric notion of selfsimilarity became a paradigm for structure in the natural world. Nowhere is this principle more evident than in the world of botany”. Self-similarity appears in objects as diverse as leaves, mountain ranges, clouds, and galaxies. Figure 1(a) shows a Koch curve, created using simple geometric rules. In the figure 1(b) is reproduced a broccoli (Brassica oleracea) which is an example of self-similarity in nature.
a)
Figure 1:
b)
Koch curve (a) and the broccoli (b) are fractals.
2.2 The Iterated Function System Iterated Function System (IFS) is another fractal that can be applied in the architecture. Barnsley [15, p. 80] defined the Iterated Function System as follow: “A (hyperbolic) iterated function system consists of a complete metric space (X, d) together with a finite set of contraction mappings wn: X→ X with respective contractivity factor sn, for n = 1, 2,.., N. The abbreviation “IFS” is used for “iterated function system”. The notation for the IFS just announced is { X, wn, n = 1, 2,.., N} and its contractivity factor is s = max {sn : n = 1, 2, …, N}.” Barnsley put the word “hyperbolic” in parentheses because it is sometimes dropped in practice. He also defined the following theorem [15, p. 81]: “Let {X, wn, n = 1, 2, …, N} be a hyperbolic iterated function system with contractivity factor s. Then the transformation W: H(X) → H(X) defined by:
W ( B ) = ∪ nn = 1 w n ( B ) WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
(1)
166 Eco-Architecture: Harmonisation between Architecture and Nature For all B∈ H(X), is a contraction mapping on the complete metric space (H(X), h(d)) with contractivity factor s. That is: H(W(B), W(C)) ≤ s⋅h(B,C)
(2)
for all B, C ∈ H(X). Its unique fixed point, A ∈ H(X), obeys
A = W ( A) = ∪ nn=1 wn ( A)
(3)
and is given by A = lim n→∞ Won (B) for any B ∈ H(X).” The fixed point A ∈ H(X), described in the theorem by Barnsley is called the “attractor of the IFS” or “invariant set”. Bogomolny [16] affirms that two problems arise. One is to determine the fixed point of a given IFS, and it is solved by what is known as the “deterministic algorithm”. The second problem is the inverse of the first: for a given set A∈H(X), find an iterated function system that has A as its fixed point [16]. This is solved approximately by the Collage Theorem [15, p. 94]. The Collage Theorem states: “Let (X, d), be a complete metric space. Let L∈H(X) be given, and let ε ≥ o be given. Choose an IFS (or IFS with condensation) {X, (wn), w1, w2,…, wn} with contractivity factor 0 ≤ s ≤ 1, so that
h( L,∪ nn =1 wn ( L )) ≤ ε ( n =0)
(4)
where h(d) is the Hausdorff metric. Then
h( L, A) ≤
ε 1− s
(5)
where A is the attractor of the IFS. Equivalently,
h ( L , A ) ≤ (1 − s ) − 1 h ( L , ∪ n =1 w n ( L )) (n=0)
(6)
for all L∈H(X).” The Collage Theorem describes how to find an Iterated Function System whose attractor is “close to” a given set, one must endeavour to find a set of transformations such that the union, or collage, of the images of the given set under transformations is near to the given set. Next figure 2(a) shows a fern created using the IFS. The IFS is produced by polygons that are put in one another and show a high degree of similarity to nature. The polygons in this case are triangles. Figure 2(b) illustrates the Collage Theorem applied to a region bounded by a polygonalized leaf boundary [15, p. 96].
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(a)
Figure 2:
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(b)
Fern created using the IFS (a). Collage Theorem applied to a region bounded by a polygonalized leaf boundary (b).
Fractal geometry in architecture
A discussion of fractal geometry applied in architecture can lead to ambiguous territory [17–19]. It is worthwhile mentioning that an architectural element is only approximately fractal, since it cannot have details that are infinitely small; thus, we prefer not to speak of “fractal architecture,” but rather of architecture “with fractal components.” This is in agreement with other studies [20]. 3.1 Self-similarity in architecture When we write about the presence of the self-similarity in architecture, we refer of a same shape repeated in different scales more than four times. We can classify the presence of the self-similarity in architecture in two different ways: • unintentional, when the fractal quality has been chosen for an aesthetic sense (e.g., in the Hindu architecture); • intentional, when the fractal component is, in every case, the result of a specific and conscious act of design (e.g., in the modern architecture). It is interesting to analyze the self-similarity in different cultures and in different architectural styles (e.g., Hindu, and Gothic styles) and in different cultures (e.g., African and Oriental cultures). Hindu temples present a fractal structure. The temple is the most characteristic artistic expression of Hinduism. The temple reflects the ideals and way of life of those who built it and for whom it was intended to operate a link between the world of man and that of the gods. In order to understand the architectural forms of the Hindu temple it is necessary to investigate the origins and development of the civilization that produced it. In older cultures the mountains prefigure the sacred sanctuaries around the world. In the Hindu experience the idea of the archetypal mountain of existence is mythologized in the cosmic mountain named Meru, the mythological center or navel of the WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
168 Eco-Architecture: Harmonisation between Architecture and Nature universe. George Mitchell (1988) writes: “In the superstructure of the Hindu temple, perhaps its most characteristic feature, the identification of the temple with the mountain is specific, and the superstructure itself is known as a “mountain peak” or “crest” (shikhara). The curved contours of some temple superstructures and their tiered arrangements owe much to a desire to suggest the visual effect of a mountain peak” [21, p. 69]. Figure 3(a) shows an Indian temple, which presents fractal components. In the Western architecture we can find the oldest handmade fractal object in the Cathedral of Anagni (Italy). Inside the cathedral, built in the year 1104, there is a floor, which is adorned with dozens of mosaics, each in the form of a Sierpinski gasket fractal. The self-similarity is also present in the Gothic Cathedrals, as shown in figure 3(b). The Gothic is a style developed in northern France that spread throughout Europe between the 12th and 16th centuries. The term “Gothic” was first used during the later Renaissance by the Italian artist Giorgio Vasari (1511-1574), as a term of contempt. He wrote: “Then arose new architects who after the manner of their barbarous nations erected buildings in that style, which we call Gothic”. Fulcanelli, the 20th century most enigmatic alchemist, gave another explication of the term Gothic, which is connected to the language of the alchemy [18, p. 84].
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Figure 3:
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Hindu temple (a) and Gothic Cathedral (b) show the self-similarity.
The fractal geometry is present in the African culture. Ron Eglash, in his book entitled African Fractals (1998), presents a wealth of examples of fractals in African architecture, and design. Eglash points out that the African WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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architecture reflects both the social and religious structure of the settlement. All the architectural examples exhibit fractal components as a consequence of some structural or organisational feature of the settlement. From a political perspective, Eglash writes: “Thus fractal architecture was used as colonial proof of primitivism. This debate over the urban status of non-Euclidean settlements continues in the postcolonial era” [22, p. 196]. He suggests that European settlers considered most African settlements to be large villages instead of cities, because instead of the Euclidean arrangements of European cities, they found complicated fractal arrangements. Figure 4(a) shows an aerial photograph of Ba-ila settlement, before 1944, situated in the Southern Zambia (Africa) [22, p. 27]. The settlement as a whole has the same shape: it is a ring of rings. Each extended family’s home is a ring-shaped livestock pen, with a gate on one end. Progressing around the ring, the buildings become progressively larger dwellings, until the largest, the father’s house, is opposite the gate (hence at the back of the pen). Figure 4(b) illustrates its fractal generation [22, p. 27]. Self-similar organisations are present in Mokoulek (Cameroon), one of the Mofou settlement, and in some Senegalese settlements. Fractal components are also present in the Buddhist temples. Borobudur, the great Buddhist stupa on Java (Indonesia), built and decorated perhaps before 800AD, should be on anybody’s list of the ten greatest art-complexes in the world for its size, quality, sophistication and excellent state of preservation. The structure, composed of 55,000 square meters of lava-rock, is erected on a hill in the form of a stepped-pyramid of six rectangular storeys, three circular terraces and a central stupa forming the summit. The whole structure is in the form of a lotus, the sacred flower of Buddha. The temple at Borobudur shows some fractal components, in particular the self-similarity (figure 5(a)). It is certainly the world’s largest mandala. Mandalas are sacred circular diagrams from the Tibetan tradition; an example is shown in figure 5(b).
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Figure 4:
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Ba-ila settlement (a) and its fractal organisation (b).
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Figure 5:
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Borobudur (a) and the mandala (b) show the self-similarity.
3.2 Iterated Function System in architecture Gothic architecture can be observed using the iterative function system. Figure 6(a) illustrates an attempt to find an IFS which could generate the ideal Gothic Church conceived by Eugène-Emmanuel Viollet-le-Duc (1814-1879). Figure 6(b) shows a fern generated by the computer using algorithms based on IFS.
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Figure 6:
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Ideal Gothic church (a), and the fern (b) could be generated using IFS.
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The Duomo (1386-1577, Milano), shown in figure 7(a), is the biggest and greatest late gothic architecture in Italy. The cathedral is white marble, over a brick core, and has a cruciform plan. One of the largest cathedrals in the world (14,000 square yards) it was designed to accommodate 40,000 worshippers. Figure 7(b) shows a Celosia Plumosa, which has the same fractal-like organisation of the facade of the Duomo.
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Figure 7:
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Duomo (Milano, Italy) (a), Celosia Plumosa (b) show the same fractal-like organisation.
Figure 8:
Santa Croce (Florence, Italy) an attempt to find the IFS.
Santa Croce, the church of the Franciscans in Florence, is one of the finest examples of Italian Gothic architecture. It was begun in 1294, in the period that served as the transition from Medieval times to the Renaissance. It was designed by Arnolfo di Cambio (1240-1302), and it was finished in 1442, with the exception of the 19th century Gothic Revival facade and campanile. The church WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
172 Eco-Architecture: Harmonisation between Architecture and Nature is simple basilica style with a nave and two isles. Figure 8 illustrates the west facade of Santa Croce, and an attempt to dissect it in triangles to find the IFS connected to the church. The iterated function system applied to the Gothic cathedrals could help us to understand the generative processes of these complex buildings.
4
Conclusions
In the field of architecture, the fractal geometry is used in many ways: unintentionally and intentionally. In architectural design is important to provide harmony between old and new. Fractal geometry can be used in the process of supporting creativity in the ideation of new forms and for testing harmony between old and new. It is helping to define new architectural models and an aesthetic that has always lain beneath the changing artistic ideas of different periods, schools and cultures [9, 10, 17–20, 23–25]. The use of the iterated function system (IFS) for generating town-like patterns has been described by Woloszyn [26], who illustrates how the iteration of a simple substitution rule from an initial and basic pattern leads to an image that looks like an urban structure. Recent studies introduce a genetic-like approach, allowing interpolation, alteration and fusion of different urban models, and leading to global or local synthesis of new shapes. These studies reveal that the IFS could help to create new pseudo urban models based on fractal algorithms [27]. Thus, it could be possible to encode simplified 2D½ city models using an IFS compression technique.
References [1] [2] [3] [4] [5] [6] [7] [8] [9]
Blackwell, W., Geometry in Architecture, John Wiley & Sons, London, 1984. Hargittai, I. & Hargittai, M., Symmetry: A Unifying Concept, Random House, New York, 1996. Williams, K. (ed.), Nexus 1, Mathematics and Architecture, Edizione dell’Erba, Fucecchio, 1998. Badaway, A., Ancient Egyptian Architectural Design, University of California Press, Berkeley, 1965 Williams K. (ed.), Nexus I1, Mathematics and Architecture, Edizione dell’Erba, Fucecchio, 2000. Sala, N. & Cappellato, G., Viaggio Matematico Nell’Arte e Nell’Architettura, Franco Angeli, Milano, 2003. Dunlap R.A., The Golden Ratio and Fibonacci Numbers, World Scientific, Singapore, 1998. Venturi, R., Complexity and contradiction in architecture, The Museum of Modern Art, New York, 1992. Jencks, C., Complexity definition and nature’s complexity, Architectural Design, n. 129, pp. 8-10, 1998. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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[10] [11] [12] [13] [14] [15] [16] [17]
[18] [19] [20] [21] [22] [23] [24] [25] [26] [27]
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Eaton, L.K., Fractal Geometry in the Late Work of Frank Lloyd Wright: the Palmer House. Nexus II: Architecture and Mathematics, ed. K. Williams, Edizioni Dell’Erba, Fucecchio, pp. 23-38, 1998. Sala, N., The presence of the Self- Similarity in Architecture: Some examples. Emergent Nature, M.M. Novak (ed.), World Scientific, Singapore, pp. 273-283, 2002. Fivaz, R., L’ordre et la volupté, Press Polytechniques Romandes, Lausanne, 1988. Mandelbrot, B., The Fractal Geometry of Nature, W.H. Freeman and Company, 1988. Oppenheimer, P., Real time design and animation of fractal plants and trees. Computer Graphics, 20(4), pp. 55-64, 1986. Barnsley, M.F., Fractals everywhere. Academic Press, Boston, 2nd edition, 1993. Bogomolny, A., The Collage Theorem. Retrieved September 15, 2005, from: http://www.cut-the-knot.org/ctk/ifs.shtml Ostwald, M.J., “Fractal Architecture”: Late Twentieth Century Connections Between Architecture and Fractal Geometry, Nexus Network Journal, vol. 3, no. 1 (Winter 2001), http://www.nexusjournal.com /Ostwald-Fractal.html Sala, N. & Cappellato, G., Architetture della complessità, Franco Angeli, Milano, 2004. Bovill, C., Fractal Geometry in Architecture and Design, Birkhäuser, Boston, 1996. Capo, D., The Fractal Nature of the Architectural Orders, Nexus Network Journal, vol. 6 no. 1 (Spring 2004), http://www.nexusjournal.com/ Capo.html Mitchell, G., The Hindu Temple: An Introduction to Its Meaning and Forms, University of Chicago Press, Chicago, 1988. Eglash, R., African Fractals, Rutgers University Press, New Brunswick, 1999. Jencks, C., The New Paradigm in Architecture. The Language of Postmodernism, Yale University Press, New Haven, USA, 2002. Soddu, C., Gencities and Visionary Worlds, C. Soddu (ed.), Generative Art 2005 Proceedings, pp. 11-24. Salingaros, N., Fractals in the New Architecture, Archimagazine, (2001), http://www.archimagazine.com/afrattae.htm Woloszyn, P., Caractérisation dimensionnelle de la diffusivité des formes architecturales et urbaines, Thèse, Laboratoire CERMA, Nantes, 1998. Marsault, X., Generation of textures and geometric pseudo-urban models with the aid of IFS, Chaos and Complexity Letters, vol. 1, n.3, Sala N. (ed.), Special issue dedicated to the Chaos and Complexity in Arts and Architecture, 2005, pp. 109-126 (in print).
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Symbols, metaphors, analogues: seeding, modelling and achieving sustainable design R. J. Koester Ball State University, USA
Abstract This paper describes the role of abstraction in providing informational structure to the complex tasks of the design-for-sustainability process and the use of that abstraction in facilitating the participation of the many players needed to assure the successful execution of projects. The distinction is made between “seeding” and “modelling” as parts of an iterative function in service to design-for-sustainability. Distinctions are drawn between the trappings of the labelling and symbology associated with systems used to index sustainable performance (such as the US Green Building Council LEED Rating System), the role of both computer-based and hands-on simulation/emulation tools used to quantify sustainable performance, and the inspirational evidence to be found in nature as exemplary embodiments of sustainable performance—all of which can contribute support to the integrative process needed to assure the effective pursuit of design-for-sustainability. Specifically, discussion is provided of the distinctions between symbol, metaphor, and analogue. In addition, critique is made of Ecological Design and Open Building Design as used to promote sustainable design. Only by clarification of the respective distinctions and with a thorough understanding of the strengths and weaknesses of each of these, as a tool, can we be prepared as designers to seed and model—and thereby effectively achieve—a sustainable architecture. Keywords: symbol, metaphor, analogue, modelling, design process, green design, ecological design, open building, sustainable design.
1
Introduction
In the face of the pervasive social concern for environmental, social and economic sustainability and the need to find ways to integrate this content into WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060181
176 Eco-Architecture: Harmonisation between Architecture and Nature the design, delivery and operation of sustainable facilities, numerous ideas are put forward; terms of definition are invoked and references are made to describe the complexity of this challenge. Nonetheless, confusion readily occurs. Terms such as green design, sustainable design, and ecological design are used interchangeably. Well-intentioned rating methods such as LEED, Green Globes, and BREEAM equally can serve to cloud the conversation. As designers, our first response to the confusion is to find ways to gain control over the overwhelming nature of this information. The use of design guidelines, lists of issues, performance diagrams and singular terminology all reflect an effort to gain that control. This paper examines this landscape to propose a specific, rather simplified means by which conceptual abstractions can serve to clarify and give informational structure to this otherwise confounding new field. More specifically, the interest is to preserve the useful operation, intent and understandings of the traditional design activity so as to leverage the proposed abstraction as a service to the looming goal of design-for-sustainability. 1.1 Abstraction as Informational Structure The most common operational tool used by architects and allied design professionals to give structure to complexity is the infamous “back of the envelope” diagram. Such a diagram often illustrates proposed performance and employs what are best described as “smart” arrows. The illustration typically patterns the flow of environmental forces in desirable ways but is not necessarily derivative of an actual mapping of the true effect of the built-form-influence on such environmental force flow. In addition to the diagram of course, design professionals frequently use the “back of the envelope” label which seeks to capture core ideas not only for talking with clients and consultants, but also to ‘spirit’ the project by painting a mental image to which participants can aspire. In either case, whether using a diagram or label—or even a sentence or paragraph imagining of the design intent—the purpose is to give structure to information. The challenge to design-for-sustainability is to systematize the conventions of abstraction so as to better support the design process; and especially to assure the clarity of roles, and active participation, by all players. 1.2 Sustainable design in all its complexity Sustainability as a topic and the design of sustainable facilities as a task allude to a complexity that exceeds the fundamental understandings of building construction; this is true as well in landscape design. Quite separate from the complexities of material choice, assembly and operation, which comprise the standard accountability in facility or landscape design, the invocation of the sustainability mantra necessitates even more careful monitoring of the metrics— with specific attention to the expected behaviour of day-to-day, life-long operational performance. This necessary obsession with tracking flows and balances so as to assure sustainability, frequently involves the use of computer software modelling and/or hands-on simulation techniques by which the predictability of operational behaviour is given some sense of certainty. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Such complexification of the process demands evermore clarity in the informational abstraction and organizational structure used to affect the process of design and the delivery of a fully functioning final project. This is exacerbated even further when considering the need to move from the more sequenced (asynchronous) contribution by the players to the more simultaneous (synchronous) interaction of the many allied professionals. 1.3 Early participation by all The sequence of conventional design service delivery which aggregates activity in phases from site selection and analysis, to programming, to schematic design, to design development, to construction documentation, to bid supervision and even post-occupancy evaluation necessitates a new look when faced with the complexities of sustainability. A more appropriate approach recognizes that all participants should be at the table from Day 1 so that the overlapping influence of concerns on the wholeness of the project can be examined, debated, and cyclically edited in an expansionist/contractionist charette process. This needed participation by all players throughout the process emphasizes the utility of simplified abstraction in giving structure to the communication of interaction.
2
Narrative
In many ways the challenge we face in seeking to design sustainable facilities is the challenge of picking a starting point in the process. The conventions of design practice and the staged sequencing of design development as mentioned above typically point toward the use of checklists to enrich the standard model of design service delivery while not changing it fundamentally. But the integrated nature of sustainable performance argues in favour of changing the process; the sections which follow present the means by which such change can occur. 2.1 Seeding is not modelling The starting point for any design is a ‘seeding’ exercise; that is to say one must have some notion of organizational purpose, diagrammatic arrangement, material selection, and/or mandate from the client that sets in place a first definition of the fixed and the variable in the decision making tree. ‘Seeding’, however, is not the same as ‘modelling’ and it is important to get at the distinction between the two. They are linked, even closely aligned; but, they are radically different. For purposes of this paper, ‘seeding’ is defined as having to do with ordering ideas and ‘modelling’ is defined as having to do with operational behaviour. 2.1.1 Seeding Many stories are available regarding the beginning point of design. Architects have been known to start with a building (as a type) that they have designed before and to look toward modifying its plans and sections as a new fit in a new circumstance (client, context, site, etc.). This approach reflects a kind of artificial structuring of problem complexity in that the imposition of the seeding WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
178 Eco-Architecture: Harmonisation between Architecture and Nature idea although seeming somewhat arbitrary intentionally begins as a “bad” fit (in detailed terms) so as to make it possible to enter the complexity of the problem space at a high level of organizational control—thereby leading to the meaningful genesis of a subsequent “good” (more sophisticated) design fit. The blessing of such approach is that one starts quickly; the accompanying curse is that one may lose the histories of rationalization embedded in the seeding idea. Nonetheless, this is a tremendously useful technique to kick-start a new project. Many stories can be told. In tracing the work of any great architect we can see in subsequent work the seeds of design ideas embedded from prior projects. These show up often in literal terms—in the plan and/or section footprints of the buildings, the choice of materials, the proportionalities of space, the geometries of alignment and/or the placements of the buildings on the land. Often these reflect a continually evolving basis by which specific responses to environmental forces are made. 2.1.2 Modelling In contrast, the modelling of problem solutions and ramifications of design decision-making can be carried out using accepted “tools of the trade” such as checklists, design guidelines, code-based mandates, strictures for established best practices, and/or computer software. In these cases, the modelling is actually a projection of expected operational performance based on the known behaviour of the pre-existing proven design. A consultant, who applies this approach as an energy-system modeller, for example, will frequently start with a go-to model of a known building (by type) and simply ‘tweak’ it to approximate a proposed design; informing and challenging the conversation about the engineering of force flows and the management of systems behaviour. The point to be made involves the distinction between ‘seeding’ as a real-time action meant to precipitate real-time behaviour of participants in the design process and ‘modelling’ as a virtual-time emulation (or mimicking) of the expected real-time behaviour of the building. It is important also to discuss how the design process can be driven by a visionary inspiration. 2.2 Inspirational evidence in nature Nature herself is one of the best teachers regarding the visualization of design process and the interactive characteristic of limits and expression. We could discuss the inspirational aspect of nature by connecting the potentiation of DNA to expressions of cellular (read built) growth in response to environmental constraint. We could expand this to include a Darwinian observation regarding the development of species (read building type) and the differentiation of each of these relative to their respective operational islands (read biomes, climates, and building sites). More generally though, the invocation of nature is helpful in talking about operational principles. 2.2.1 Location, form, metabolism Nature teaches that animals and plants function in response to environmental force by modifying location, form and/or metabolism. Animals, for example, WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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migrate from point A to point B to escape the less favourable, or to enjoin the more favourable conditions; both animals and plants differentiate form to expand or contract exposure to the elements; and animals activate metabolic function to compensate for environmental stress. These rather straightforward teachings are found in the migrations of birds or butterflies from winter to summer seasons; the form (and size) of Elephant ears used to promote thermal exchange; the on-the-spot shivering by animals as a metabolic activity in direct response to the environmental constraint. 2.2.2 Form, operation, appearance These factual aspects of physiologic fit of a species to environment can be contrasted also against the more poetic inspirational evidence in nature. It is not uncommon for designers to invoke themes of form, operation, and/or appearance in that regard. The bird-wing quality of the Milwaukee Art Museum by Calatrava (Aldersley-Williams [1]), the differentiation of the skin of the Phoenix Public Library by Bruder (Wigginton and Harris [2]), or the physical form of the Fish Dance Restaurant by Gehry (Aldersley-Williams [3]), exemplify this point.
3 Trappings The conventions of practice as referenced in the introduction yield a kind of trap for the designer; when burdened by the labels and symbols invoked. 3.1 Labelling One example of labelling, established as a formal evaluative system, is the US Green Building Council Leadership in Energy and Environmental Design (LEED) scoring technique. With this method, one can obtain designation for a building as operating at levels of performance meriting the ratings of certified, silver, gold, or platinum. Proponents of the system even argue in favour of “exceeding LEED” by achieving living building performance. The simplified scoring system which involves a substantial interactive review process reflects a disassociation of actual performance and operational behaviour at the level of content and supplants that measured performance with the simplified terminology of the label itself. In fact, the most recent literature is reporting that some of the LEED certified buildings are not performing as intended (Schendler [4]); in part because some have achieved their scores while paying minimal attention to energy flows—an important element of sustainability. 3.2 Symbology In contrast to the scoring method and the trappings of the certification labels, there is a latent symbology embedded in popular design terms such as green, ecological, sustainable and even regenerative design. These are used often in overlapping and interchangeable ways and lack clear agreed-upon definitions. Is a green building a sustainable building or is a sustainable building green? Can a living machine alone make a building green? Is a building green only when WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
180 Eco-Architecture: Harmonisation between Architecture and Nature measured in terms of materials or is it green because of its energy behaviour? Is a sustainable building only sustainable because of the sourcing of material or because of its operational performance? The confusions aggregate quickly. The point to be made is that we must guard against the trappings of language and we must be careful not to invoke symbology as a substitute for content when faced with the tasks of design-for-sustainability. One of the most tried and true examples of symbolic invocation is the use of the sun path diagram on a building plan or section. The minute one puts this on the sheet, the building is ‘labelled’ a solar building and the presumption is that it will perform at some level of accepted best practice. What the labelling does not do is explain in any detail what the 8760 hour track of performance will be during a typical meteorological year, nor does it get at the interaction of the various systems or design strategies used to assure some level of expected operational performance.
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Tools
There is a wide range of computer software on the market by which one can simulate the behaviour of intended building performance. This includes energy, lighting, acoustics, finances and the life-cycle evaluation of material impacts. 4.1 Thermal The most robust energy modelling tool in the United States is DOE-2 which requires a complex description of building energy components; it uses sophisticated thermal network modelling to mimic the trade-off of energy gains and losses in the capacitance of a building’s spaces and materials over the course of days, weeks, and months—as influenced by the dynamic occupant and climate loads. Other tools, such as Energy Plus, Energy-10, Energy Scheming (a more qualitative inferencing tool), and Eco-Tec all utilize similar network modelling of energy flows as thermal capacitance trade-offs. Nonetheless, even the most sophisticated application of these modelling tools does not yield absolute assurance of final performance. The tools simply put a design idea “in the ballpark”; more importantly they give reasonable assurance that the system choices made have a mutual, internal integrity of performance as they interact. 4.2 Luminous The most prominent tool in lighting simulation is Radiance which is used to create pictorial imaging of rendered computer models with a back-up technical accounting of performance metrics. The software offers effective visualizations of expected final appearance of light behaviour in a space based on known reflectivity and co-efficiencies of absorption for materials selected as room surface finishes. Factored into such models are fairly accurate predictions regarding the influence or impact of hard light from the sun and the inter-reflective light from the sky-vault. The sophistication of these rendering capabilities, however, falls short of the need for quick iterative feedback during the process of design. As a result, many lighting designers use more immediate WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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modelling techniques such as Heliodon and/or Sky Chamber Daylight emulators which enable the participants to work in real time to make quick decisions and test options ‘on the fly’. Most importantly, these modelling tools are useful in feeding and/or otherwise supporting conversation among the allied professionals contributing to the work, since all of them can be at the table at the same time. 4.3 Acoustic A popular software tool for acoustical evaluation is CATT-Acoustic, which calculates the reverberation effect and inter-reflective accumulation of wave phenomena in a physical space based on material choices, space geometry and contained air volume. The tool is quite helpful in emulating the acoustical quality and can lead to an understanding of the expected technical regimes for reverberation and the noise deadening effects of materials and space geometry. Nonetheless, in the end, acoustical spaces are only able to be fine-tuned (perfected) using more empirical trial-and-error methodologies in the field; “sparking” a point signal, measuring actual reverberation time and profiling the frequency response of a space can only be made on location in real-time. 4.4 Financial Numerous tools are available for doing life-cycle cost (LCC) analysis and/or day-to-day return on investment (ROI) profiling using assumptions about capital costs, discount rates, longevity of the project, annual operating expenses, and other variables of influence. These financial models can be used to track the trade-off of higher front end costs against lower operational costs yielding a cost-benefit over time. Interestingly, these modelling tools enable the capture of the interactive nature of system design; buildings that score LEED Silver often cost less to effect than those meeting Certified rating. The internal trade-offs and multiplying effects of the conservation efforts accumulate with the greater level of sophistication indicated by the higher performance rating. 4.5 Life Cycle In contrast to costs, tools are available for determining a Life Cycle Assessment (LCA). These measure the net environmental impact of materials as tracked from the point of sourcing through manufacture to delivery and operation. The more notable software tool on the market that engages this kind of profiling is that of the Athena Software Group. Life Cycle Assessment also looks at operational use in place and tries to establish the benchmarks for replacement or repair needed during the ongoing maintenance and operation of a facility. Both of these involve a sophistication that exceeds conventional architectural service.
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Discussion: a wilful simplification
In the light of the discussion above, there is need for clarity of conceptual structure. The three terms discussed below are offered as that device. They WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
182 Eco-Architecture: Harmonisation between Architecture and Nature comprise a kind of graded invocation of understandings that distinguish the trappings, inspirations, and metrics of design ideation—especially as these involve all contributing parties working in service to design-for-sustainability. 5.1 Symbol For sake of definition, the symbol is seen as iconographic; a signal of intent, a marker of content, but is not itself considered operational. As described above, the symbol “stands for” operational performance as a measure of sustainability. The LEED rating system, the sun-path diagram, or even the labelling of a plan and/or building cross-section with so-called smart arrows, tend more to be “calls for” intended performance rather than measurable predictions. Such symbols need to be qualified for what they are to distinguish their more superficial level of information structuring from those which are more penetrating. 5.2 Metaphor For the sake of definition, the metaphor is seen as an allusion and is used to establish a spirit for the project. A building can be imagined to be “as a bird on a nest”; or seen to be structured “as a spider’s web”, or could have experiential qualities “as in the space of a cave”. Metaphors allude to a qualitative feel as well as an organizational inference, but do not talk to specific operational practice or expected (let alone, measured) performance. 5.3 Analogue By contrast, the term analogue is used to talk about the operational aspects of models—especially those in nature—that can be used to inform design. Analogues are those physical performances that can be mimicked in built form. The chimney-effect ventilation of a tall building as analogous to the natural stack-effect ventilation of the termite mound is a profound example.
6
Critique
The proposal herein is to use the three terms above to describe, interpret, and/or otherwise employ the widely-available labels, diagrams and tools of design-for-sustainability. Moreover, the goal is to leverage other bodies of architectural work and schools of thought whose origins and/or histories do, or do not, have an immediate connection. To emphasize this point, the following two critiques are made of Ecological Design and Open Building, respectively. 6.1 Ecological design Much of the concern for sustainability in architecture and allied design fields operates under the rubric of ecological design. A simple web search yields all manner of definitions and/or interpretations of the term. There are numerous practicing professional groups and individuals that weave this into the titling of WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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their company; design-build and professional schools of architecture throughout the world invoke the term as part of their curricular descriptions, if not degree titles; and various manufacturers invoke the term to describe their products. Organizations, institutes and centers use this term as well; one of the most notable is The Ecological Design Institute (Van der Ryn [5]) which offers namesake guidelines: (1) Solutions grow from place (2) Make nature visible, (3) Design with nature, (4) Ecological accounting informs design, and (5) Everyone is a designer. Another checklist example comes from Malcolm Wells, the so-called underground architect whose work predated much of the contemporary concern for environmental, economic and social equity formalized as the sustainability interest; Wells compiled an intriguing matrix by which designers could score their projects—whether buildings or landscapes. The list provides a simple polarity of qualitative measures regarding how a design “contributes” to the creation of pure air or destroys it, “creates” pure water or destroys it, etc. (SBSE [6]). A forest landscape, of course, merits a perfect score. 6.2 Open building Of the many schools of thought that have bearing on the process of facility delivery as well as use, Open Building is perhaps one of the more internationally recognized in the literature. Open Building aggregates design decisions in time and space on five levels — urban structure, urban tissue, base building, fit-out, and furnishings. And between each of these, defines the territorial units of town, neighbourhood, functional areas (or departments), and rooms. The concepts grow from the early writings of Habraken [7] regarding supports and infill as a means of conceiving elements of a building which have differing physical lives. Open Building aligns itself with the idea that since base buildings and urban infrastructure have the longest lives of the systems, they can be designed and evaluated using a 100 year life-cycle. The literature on Open Building is well developed, but the integration of sustainability factors is not fully developed or well refined (Koester et al. [8, 9]). The categorizations of symbol, metaphor and analogue can help Open Building designers address more effectively the issues of environmental fit at each of the levels, and appropriately import the resource materials needed to support the nested levels of decision-making.
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Conclusion
In the face of the sustainability concerns, the challenge is to find ways to bring all players to the table using a language of categorization by which discussion can be anchored. The proposal in this paper is to use the simple hierarchy of symbol, metaphor, and analogue as a way to stimulate kinds of discussion, categorize available resources, identify design process activities, and inventory design documentation. The simplicity of the terms and the clarity of their definition will promote dialog and establish a hierarchy of appreciation for the complexity of the task of achieving sustainable design. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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References [1] [2] [3] [4] [5] [6] [7] [8] [9]
Aldersey-Williams, H. Zoomoorphic: a new animal architecture. HarperCollins: London, pp. 50-51, 2003. Wigginton, M and Harris, J., Intelligent skins. Elsevier, Amsterdam, pp.99-102, 2002 Aldersey-Williams, H. Zoomoorphic: a new animal architecture. HarperCollins: London, pp. 47, 2003. Schendler, A and Udall, R., LEED is broken; let’s fix it., 2005 http://www.grist.org/comments/soapbox/2005/10/26/leed/index1.html. Van DerRyn, Sim., The ecological design institute., 2005 http://www.ecodesign.org/. SBSE, A regeneration-based checklist for design and construction., 2005 http://www.sbse.org/resources/index.htm. Habraken, N.J. The structure of the ordinary: form and control in the built environment. MIT Press: Cambridge, pp. 1-100, 9999, 1998. Koester, R., Open building and community harvest: new definitions of what can comprise a base building. Proceedings of the 2005 World Sustainable Building Conference, Tokyo, pp. 2976-2982, 2005. Koester, R., Dettbarn, D., and Riegle, E., Tectonic constraint: harvesting material(s) -- and building(s) -- to seed sustainable architecture. Proceedings of the 21st International Conference Passive and Low Energy Architecture (PLEA), Eindhoven, pp. 571-576, 2004.
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A methodology for sustainable design analysis of large scale buildings R. Richarde1 & R. Ibrahim2 1
Department of Architecture, California Polytechnic State University, USA 2 Construction Engineering & Management Program, Stanford University, USA
Abstract Long-term sustainability—including maintenance, operation, and life cycle cost analysis—should start during the concept design stage where most critical decisions are determined. This paper provides advice for owners, facility managers, and designers to optimize sustainable design options. Furthermore, by front ending the costs for implementing those design options, owners return on their investments are likely to be long term, they are likely to have reduced operational maintenance costs, and are likely to have an increase in global energy conservation. This paper proposes how to formalize a “Sustainable Methodology” (SM) to facilitate effective contributions by decision makers during the early concept design stage of a facility development project. The SM framework has five phases: input, evaluation, summarization, synthesizing, and output. These phases are initiated by the owner’s preliminary architectural program and sustainable design goals, starting with site planning. The site planning elements are climate (macro- and micro-climate), orientation, use, function, shape/form, and surrounding (landscaping and buildings). The SM framework evaluates planning elements and suggests implementation options in harmony with environmental sustainability objectives. In addition, this paper describes how the SM framework was tested on a multi-story mixed-use development project during its site planning. Further studies can extend the SM framework to include other aspects of facility design such as envelope, structure, services, and space planning. Keywords: concepts, elements, phases, layers, components, scenario, strategy.
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1
Introduction
According to Knowles [1], given that a building has a forty years life span, the cost of the design process usually is about 10% of the initial budget cost, the cost of construction is 30-40% of that budget, and the remaining 60% is usually spent on maintenance and operations. Large scale buildings contribute significantly to resource consumption, as well as to other environmental impacts, such as air emissions and solid waste generation and 17% of the total year-2000 US primary energy consumption [2]. Fossil fuel production has already peaked, and it is generally agreed that we are now in an era of declining oil production. With the resultant higher fuel costs, and the uncertainty surrounding energy sources, the need for energy conservation will be a key issue for making economic decisions. In particular, it is reasonable to assume that an objective of building design is to create the best possible facility for a given level of expenditure that utilizes the least amount of embodied and life cycle energy. The objective during the initial development stage of a project should be to establish an effective set of design guidelines. Therefore, if a particular design constraint is essential to the proposed facility, such as incorporating sustainability issues, then the issues surrounding that constraint must be identified and provided to the designer prior to the initiation of building design. Fig.1 shows in general terms the extent to which the influence of design decisions diminishes as the building project moves forward in time. Obviously, some degree of iteration occurs during all design and construction phases but the impact of design and construction changes decreases dramatically the closer the project moves to the bidding cycle. After bidding and during construction only minor changes can occur.
Figure 1:
Time influence on design decisions.
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In order to demonstrate the importance of these design guidelines, this paper proposed an organization of a knowledge base “Sustainable Methodology” (SM) for dealing with the green design and sustainable principals. The primary concept is to provide design strategies directed to minimize future energy consumption and environmental impact. In addition, another reason for such organization is to simplify the way the design concepts are formed and generated. This study uses Stewart’s [3] model of concepts as a framework for evaluating various components of a building design. In this study, the paper builds upon a methodology using the five layers, with each layer called a concept, with elements representing different components. However, in application it suggests first to consider the site concept as the key to the successful use of the other concepts. Below are the five concepts and their elements, to be considered as tools for sustainable design in preliminary stage for multi-use building: Site: climate, orientation/solar access, shape/form, size, use, and function. Envelope: glazing, heat gain, heat loss, insulation, roof, energy efficiency, and apertures/windows, skylights, atriums. Structure: types, materials and its use, longevity, and recycled content vs. waste. Services: mechanical HVAC systems, electrical, pluming, lighting, passive heating and cooling. Space Plan (Interior): interior layout of floors, ceilings, walls, movable furnishings, and finishes.
2
Overview of the Sustainable Methodology (SM)
The SM is divided into five phases: Input, Evaluation, Summarizing, Synthesizing, and Output. Each phase provides data input for the succeeding phase, which eventually will provide the final recommendations for appropriate design options in the Output Phase, fig.2. Following is an overview for the five phases: Phase I – Input Phase: This phase identifies an owner’s initial project idea. It introduces a preliminary architectural program at the pre-design phase that leads to prioritizing the owner’s design goals in regards to sustainability. This process usually leads to identifying a specific site that may meet the above goals, and specific guidelines to consider for sustainable site development and evaluation. Phase II – Evaluation Phase: After a site has been selected, the evaluation of all available options for envelope, structure, services, and space planning elements follow. This evaluation is based on sustainable design options and the choice of the elements refers to the original sustainable design goals. Phase III – Summarizing Phase: This phase involves summarizing the evaluations of available options, and performing a prioritization process
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188 Eco-Architecture: Harmonisation between Architecture and Nature based on sustainable design goals. The product of this phase is a ranking of the options that were evaluated from Phase II. Phase IV – Synthesizing Phase: This phase involves using the most appropriate combined and ranked interchangeable elements from the Summary Phase, then identifying synergetic elements that enable optimized design and producing strategies for envelope, structure, services, and space planning concepts. Phase V – Output Phase: In this phase, the user selects the final strategies and produces formal sustainable design recommendations that are most appropriate to the client’s goals and priorities.
Figure 2:
3
Overview of the SM Framework.
The site concept
The primary Site concept is measured, formalized, and tested because it is considered the basis on which a design will develop. The selection of the proper site and facility can make a valuable contribution to a project’s profitability. Real estate costs are a business expense, and as such affect profit. Therefore, it is vital that real estate needs are carefully analyzed to determine what is needed and not needed in terms of, use of site, physical facility requirements, physical site requirements, and regional/local considerations. In order to optimize integrations with natural ecosystems, the SM site analysis will focus on the following site elements: climate, orientation, shape/form, size, use, function, and surroundings.
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When selecting a site, it is important to consider the impact on the community planning and the environment, such as contaminated sites, agricultural sites, and conservation of environmentally sensitive sites. The object of the site analysis is to guide the creation of the shape, structure, geometry, and scale of the building so that it can maintain equilibrium under the stress of the cyclic changes of nature (seasons change, precipitation, insolation, etc.). In addition, when site elements are considered and evaluated, the site analysis will guide the conception of a building of multiple components, including envelope, structure, services, and space planning, which determine the building longevity, life cycle, maintenance, and operations. Furthermore, each one of those site elements enables the selection of appropriate components. For example, once a site location and climate consideration with solar access is identified, then form and orientation can be established, which then lead to use and function, fig. 3.
Figure 3:
4
Overview of sustainable methodology.
Case study
This paper investigates the decision process and key criteria owners and facility planners use to assess the pre-design phase, when given a preliminary program and a set of design goals. The proposed sustainable methodology (SM) for predesign analysis of large scale buildings is tested at a student housing project at one of the CalPoly campuses in Central California. The SM case study provides advice to minimize environmental impact, increase energy conservation and resource efficiency, and reduce cost over the life cycle of the project. 4.1 Background The CalPoly student housing project will provide apartment units, parking and a village centre with recreation and retail facilities for 2,700 students. The project will be comprised of 902 one, two and four-bedroom apartments and adjoining WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
190 Eco-Architecture: Harmonisation between Architecture and Nature 2,000 parking spaces. This will be the largest student housing project ever built on a public California university campus. 4.1.1 Research methodology This research is a case study research that has the following three objectives. First, to map out the decision process that occurred during the pre-design phase of SHN; second, to identify points in the decision making process where the SM can be useful; and third, to attempt to use the SM at those points and reinterpret the results as if the questions in the SM were seriously applied. The first author interviewed seven of the major space planning decision makers that had authority over the development of the CalPoly student housing project. The data of each interview were entered in a table that presented thirteen questions and answers. The results were defined by comparing the responses and by looking for internal contradictions and consistencies. Then a strategy was developed based on the client’s goals and priorities for the project, as well as the interviewer’s responses and comment (Transcribed Interviews). Finally, an assessment was made on how that strategy, fits into the proposed SM. 4.2 Recommendations 4.2.1 Identification of SM intervention There is a significant difference between the client’s early design process and goals, and the SM. The client’s priorities emphasized barbecues and attractive design versus those of SM, which emphasized human preference and energy efficiency. As shown in fig.4, when the SM was inserted in the pre-design process of the housing project, it had the potential to provide an improved process and improved results.
Figure 4:
Identification of SM intervention.
4.2.2 Orientation After careful review of the project’s site plan, it has been shown through light studies and solar analysis that the orientation of this development is rather poor. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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According to Haggard and Niles [4], cost savings of about 70% might occur with proper calculations for building orientation and thermal mass. In order to achieve such savings the following are the guidelines for natural heating and cooling: Building oriented toward the equator with a maximum deviation allowed of + or - 20 degrees. 12 to 20% of floor area in south glass. If low e glass is used it must be receiving low e Hard coat (U>.33 and solar heat gain coefficient >.65) for the south window. This south glass should be shared by approximately a 2’-6” overhang to allow summer shading while allowing winter sun in. Provide 10 square feet of any combination of the following thermal mass options for each square foot of south glass: o Interior masonry wall 2 inches or more in thickness. o Exposed concrete floor slab with a non insulting finish such as plain or colored concrete, tile, or directly applied wood or bamboo parquet. o 9 inch thick water tank directly exposed to the south light in the winter. o Double 5/8 inch thick drywall counts one-half. Ability to cross ventilate all major rooms at night with at least 4 square feet of opening on two sides per 100 square feet of floor area in order to cool the thermal mass in the summer. The above proposed 70% cost savings would make economic sense with 2,700 residents. Another advantage to proper solar orientation comes from reduced heat gains. Less heat entering the building envelope reduces the need for cooling. Natural light also reduces the need for artificial lighting, therefore it is proposed by the same report and guidelines mentioned above to have windows, skylight, or roof light tube within at least 15 feet of each other. In addition, to have all the major spaces must have natural light from two different directions. 4.2.3 Climate The climate analysis for the housing project’s location, fig.5, was based on a spreadsheet by Pena [5]. The spreadsheet creates a matrix of temperatures for the year, giving the average temperatures for two-hour intervals for each month. The spreadsheet allows a user to input temperature data, the average high and low temperature for each month, and uses these data to estimate the temperature for two-hour intervals between these high and low temperatures. The temperatures which are colored in, indicating the closed heating mode in winter, open “sailing” (no mechanical systems in operation) in spring and fall, and closed cooling periods in summer, based on assumptions for a building that has a balance point temperature of 55 degrees and a closed cooling temperature of 75 degrees. The average percent of the yellow area is 10%, blue is 45%, and white is 45%. This concludes that the climate in Central Coast area of California allows the buildings to operate without any mechanical systems almost 50-60% of the times in terms of cooling and heating.
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Figure 5:
Climate analysis.
4.2.4 Circulation Parking and a consequence of it, vehicular circulation are the main factors in energy use and pollution, per the San Luis Obispo Air Pollution Control District. In many cases, circulation contributes more to environmental degradation than inadequate building orientation. Circulation choices – e.g., the availability of attractive non-motorized modes (such as bicycling, pedestrian roads, and public transportation) – also enhance social equity. The university project’s Environmental Impact Report executed in summer of 2003, does not primarily think of alternative transportation or a shuttle bus but emphasizes an abundance of wide roads. The proposed alternative would enhance a non-motorized transportation and allows for a direct shuttle bus from the housing project to the Campus Market, campus core, and points further south. Pedestrian and bicycle paths, fully separated from roads, are proposed. This solution can easily be developed in phases, where the first phase is much less expensive than the current road concept. 4.2.5 Parking The university housing project’s site plans have proposed two main parking structures; one is at the north side of the site and the other at the south side of the site. For 2,700 beds, a full 2,000 parking spaces are now being designed, which means 0.7 parking spaces per bed. It is proposed, a first phase of 300 spaces would be ample; if demand exists, more spaces could be built later. Furthermore, this research proposes to create a single parking structure with three levels of 60,000 square feet each, for a total of 670 spaces at a ratio of 0.25 spaces per bed. The structure will be located uphill from the SHN development, partially underground (cut into the hillside) to avoid blocking views or creating an eyesore. It will be accessible from the one-way perimeter road around the complex. If this structure were to embrace the contours of the hill of the north side, then a solar roof could be devised to capture energy, shade the cars, and produce electricity for night-time street and parking structure lighting. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Eventually, electricity may be used locally or sold back to Pacific Gas & Electricity for net metering, and the power may be used to charge a fleet of electric vehicles, which would encourage the use of electric cars around the campus and reduce pollution and the use of fossil fuel (energy efficiency).
5
Conclusions
The SM for sustainable design was developed to help owners, facility managers, and designers contribute effectively during the pre-design analysis stage where most decisions are determined for the performance and life cycle of the building. It was concluded that by adopting this pre-design SM tool, positive financial profits may be generated throughout the building’s life cycle, in particular through a reduction in its operations and maintenance costs. Furthermore, the framework was successfully tested on a large-scale public California university housing project development during the pre-design analysis stage of the site. It was quite difficult to perform the pre-design analysis prior to the official expiration deadlines of the grants and funds because of many politics and bureaucracy restrictions. When comparing the CalPoly process and the SM process, this research concluded that if the university’s system had used the SM, it would have saved the decision-makers time and unneeded battles between the campus planning committee and the facility planers and developer. In addition, it would have provided the opportunity to design and rethink the traditional designs, using sustainable alternatives. This research proposes that this SM be tested on more campus projects and non-campus facilities (corporates, health care, schools, etc.) this will further enable the determination of the measure of success of the methodology at the pre-design phase. The SM framework could be used to evaluate other building design components, such as envelope, structure, services, and space planning. Future studies could enhance the SM in allowing owners to evaluate the design options before committing to a site. Finally, there is a need for a further development of the SM framework into a computational tool to provide more detailed project guidelines and recommendations. This study has defined the groundwork for more implementation of sustainable design. This may help professionals who are not as familiar with sustainable design principles and an easy way to add sustainable elements into their building designs.
References [1] [2] [3] [4]
Knowles, R., Energy and Form, MIT: Cambridge, 1974. US Green Building Council. Leadership in Energy & Environmental Design, Rating System V.2.1. Washington: USGBC, 2002. www.usgbc.org. Brand, S., How Buildings Learn, Penguin: New York, 1995. Haggard, K. & Niles, R., Passive Solar Hand Book, California: State Energy Commission, 1980.
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Pena, R. Personal communication, 23 January 2005, Professor of Architecture, California Polytechnic Institute, San Luis Obispo, California, USA.
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Developing designs in balance with nature A. J. Anselm School of Architecture and Urban Planning, Huazhong University of Science and Technology, Wuhan, People’s Republic of China
Abstract Recent developments especially in the areas of ecology and architecture have identified an unhealthy relationship between the built environment and nature. The breakthroughs in science and technology through the late 18th century saw an explosion in the trends/types of architectures that are presently characterized by their polluted, machine-dominated, dehumanizing, and environmentally unfriendly natures. This trend which in collaboration with other environmental defiant practices also contribute in the fast depleting, explosion-threatened world that is even now disintegrating and disappearing before our eyes. Time is quickly running out for our society to rethink the way we plan for development of the remaining open spaces. The main objective here is to confer ideas aimed at creating environmentally friendly, energy-efficient buildings developed by effectively managing natural resources. This entails passively and actively harnessing solar energy and using materials which, in their manufacture, application, and disposal, do the least possible damage to nature’s ‘free resources’; water, ground, and air. This involves identifying factors that affect a healthy natural environment such as choice of building site, orientation, choice of building materials (in other words, let where it is be where it is made of) and methods of combining these building materials in order to achieve balance. Keywords: designing with nature, eco-architecture, ecological designs, building with nature, sustainable designs, resource efficient design, energy efficient designs, harmonization with nature, design.
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1
Introduction
A pure natural environment is the epitome of health and vice versa, a condition that is the primary desire of all that exists within it. The earth is an emotional entity and nature, the result of its emotions. Man made and natural disasters are the means of expression of sadness or pain that the earth feels, thus when the earth hurts, nature cries, likewise when the earth is in health, nature smiles. Man’s activities through time produce adverse effects to the health of the earth and its expression through nature, and since we are all property of the earth and not left out when nature cries, it is then mandatory for man to learn means of appeasing the earth by means of harmonizing his activities with earth’s most cherished progeny… nature. The quest for an ecological understanding and approach in all of man’s endeavours and activities, has become a challenge to all that care about nature as it is obviously a systematic method of restoration back to nature, hence a more healthy earth. It is a call that should be answered totally by all professional disciplines, as one un-ecological activity can prove retrogressive to the efforts of so many. Since architecture contribute in making the built environment, ecology should then be employed as one of its vital tools or element of architectural designs. Our design and construction trend, has witnessed changes and transformations from industrialization to machinism, a trend which in recent times is characterized as unfriendly to nature. Designing and building with or in harmony with nature is the one efficient concept which works towards integrating the elements of balance between the built environment and nature.
2
Understanding the natural environment
The surface of the Earth as a whole is an Ecosystem, called the Biosphere. The Biosphere or the surface of the Earth constitutes nature’s ‘free resources’ air, water, and land, where living things exist. The Biosphere with a structure of smaller units called Ecosystems includes all the Organisms and the Nonliving Environment found in a particular place, and this also includes our built environment, an area that needs to be integrated into the ecosystem without negatively affecting the balance in the ecosystem itself. Understanding the natural environment is the first step towards achieving a nature integral design. It entails understanding nature’s environmental activities, the Ecosystem and its actions and reactions that will relate to building designs. The constant use of such analytical processes that determine and define functions of building designs and its corresponding effect to the immediate and distant environment should not be neglected. These procedures like the environmental conservation, environmental impact assessment, integrated assessment etc, which are normally undertaken for individual projects such as dams, motorways, airports or factories should be broadened to include damage assessment, ecological replacement systems or ecology integration solution for smaller project designs like commercial and residential buildings.
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Figure 1:
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The ecosystem structure.
2.1 Traditional approach; ecology integration solution An argument once arose that the one way to protect the environment is for society to place a monetary value on it, and then sue any firm or individual that damages it. But how can society measure the economic damage caused by environmental injury? The ecological replacement solution is an idea that discusses ecological solutions in a small or larger scale for the restoration of damages or injury caused by tampering with the natural (green) environment in the intent of building development. This idea has been utilized in the past based on local knowledge or unconscious attempts to balance the immediate natural environment around the built environment. Such local knowledge, usually acquired through experience and oral transmission, often accounts for the interrelationships among animals, plants, humans and the environment, resembling in some aspects ecological concepts held by scientists (Berkes et al., [3]). Thus, local ecological knowledge is an important keystone to the design and structure of natural resource management strategies. In nature there is no waste, the byproduct of one organism becomes the food for another. In other words, natural systems are made of closed loops. By working with living processes, we respect the needs of all species. Engaging processes that regenerate rather than deplete, we become more alive. Making natural cycles and processes visibly brings the designed environment back to life Building designs and construction take up natural foliage spaces or natural landforms. These natural landforms or foliage that supports some useful ecological organisms should be replaced systematically in order to ensure resuscitation of displaced plants and organisms which are also necessary for an ecological balance. The percentage of replacement may depend on the function WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
198 Eco-Architecture: Harmonisation between Architecture and Nature of the structure or architecture and also on the construction techniques employed as shown in figure 2 below. Such replacements, enhances the energy efficiency and overall thermal and environmental comfort of the area involved.
Figure 2:
3
Example of the traditional concept on ecological replacement as seen in the traditional Turf (grass covered) houses in Iceland (1), and the modern approach as expressed in the designs of architect Emilio Ambasz (2) and (3).
Managing the natural environment and resources
Designing with nature entails managing the three basic nature-resources of air, land and water. This also involves utilizing design elements and ideas that will make best use of these nature-resources and their extended influences that may be human friendly or otherwise. Careful consideration is needed in the choice of topography and terrain, and the management of climate and energy. 3.1 Orientation and choice of building site A building site is the closest environment to any proposed building plan; it forms the immediate atmosphere for the occupants of such a building and it is expected to satisfy the desires of the proposed occupants as well as satisfying the environment that will host it. Designing with nature begins with an intimate understanding of place. With active sensitivity to the nuances of place, we can inhabit without destroying it, be it a plain, undulating or steeply terrain, the landform is to be carried along in the design concept. A careful design plan and construction technique will see to less damage to the topographical structure of the building site. Understanding place helps determine design practices such as solar orientation of a building on the site, designing with existing topography pattern and finally the preservation of the natural environment, whether the WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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design site is a building in the inner city or in a more natural setting, connecting with nature brings the designed environment back to life. Effective design helps inform us of our place within nature. Regional climatic conditions or local climate which define the choices of building orientation when rightly managed and effectively considered in building design and orientation forms a source of energy conservation and management. Advanced climatic research identifies that most tropical building designs gain more in energy conservation by the use of the south/north or north-east/southwest orientation as against the east/west orientation for purposes of better wind flow, ventilation and sun shading, likewise temperate designs with the south/north alternative for the major purposes of winter heat gains. A survey indicates that most residential buildings with an elongated east-west orientation, built virtually anywhere in the United States, will experience a 10% reduction in energy consumption compared to a square building, and a 20% reduction compared to a north-south building. This then indicates that choice of building orientation can make best use of the natural conditions of a place to achieve the desired thermal comfort with or without a combined use of other sustainable energy sources like the solar photovoltaic or the wind energy generators. 3.2 Climate integrated design Climate is an inevitable member of nature and its effects some times are unpredictable. The Sun, land, and water interact in complicated ways throughout each day and throughout the year, and the result is what we commonly refer to as weather. These interactions produce daily as well as seasonal temperature, humidity, and wind patterns that can vary substantially between locations in close geographic proximity. A Climate-integrated design is a strategy that seeks to take advantage of the positive climate attributes of a particular location, while minimizing the effects of attributes that may impair comfort or increase energy requirements. A climate-integrated design should consider the following points. 1. Understand climate zones and microclimates 2. Understand the basic physiology of human thermal comfort 3. Control the sun to reduce loads and enhance visual comfort 4. Use thermal mass to improve comfort and efficiency 5. Utilize the local winds and breezes as much as can be harnessed for improved comfort. 6. Finally, effective choice of material and design technique for optimized results. The microclimate of a building site can make or break a climate responsive design, for instance to better harness the solar rays for a passive design or a solar energy design, the solar path needs to be evaluated, as shadows cast by nearby buildings, trees, or hills are important considerations in orienting a solar collector or designing a passive solar building. The proper study of the solar path can also effectively provide options of building materials or techniques for better sun shading or solar access. The Figure below shows the behavior of the sun through the seasons and the effects produced which utilized effectively can satisfy the solar requirements in a building design. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Figure 3:
Showing seasonal solar paths and shadow patterns, the major factors that may affect the orientation of a solar collector and design of a passive solar building.
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Table 1: Climate zone
TROPICAL Hot and humid
SUBTROPICAL Warm and humid
SUBTROPICAL Hot and dry/warm winter
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Design implication for varying climatic conditions. Characteristics
Design implication
-High humidity with a degree of “dry season”. -High temperatures year round. -Minimum seasonal temperature variation. -Lowest diurnal (day/night) temperature range.
-Employ lightweight (low mass) construction. -Maximize external wall areas (plans with one room depth are ideal especially for residential units) to encourage movement of breezes through the building (i.e. cross ventilation). -Shade whole building; consider using fly-roof and landscaping trees. -Use reflective insulation and vapor barriers. -Ventilate roof spaces if possible for optimized results. -Consider high or raked ceilings -Provide screened, shaded outdoor living areas, also creating sleep-out spaces (for residential). -Design and build against windy conditions and hazards. -Most essentially, design for a greener environment.
-High humidity with a definite “dry season”. -Hot to very hot summers with mild winters. -Distinct summer and winter seasons. -Moderate to low diurnal (day/night) temperature range. This can vary significantly between regions too e.g. inland to coastal
-Use lightweight construction where diurnal (day/night) temperature range is low and include thermal mass where diurnal range is significant. -Maximize external wall areas (plans with one room depth are ideal especially for residential units) to encourage movement of breezes through the building (i.e. cross ventilation). -Shade whole building where possible in summer and allow passive solar access in winter months only. -Avoid auxiliary air conditioning, good design techniques does it all. -Provide screened, shaded outdoor living areas. -Most essentially, design for a greener environment.
-Distinct wet and dry seasons. -Low rainfall and low humidity. -No extreme cold but can be cool in winter. -Hot to very hot summers. -Significant diurnal (day/night) range.
-Use passive solar design and insulated thermal mass for the external walls. -Maximize cross ventilation -Utilize convective (stack) ventilation, which vents rising hot air while drawing in cooler air. -Allow for solar access and exposure to cooling breezes -Shade all east and west windows for summer and build screened, shaded summer outdoor living areas that allow winter sun penetration. -Use trees, garden ponds and water features to provide evaporative cooling during summers.
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202 Eco-Architecture: Harmonisation between Architecture and Nature Table 1: Climate zone
HOT ARID Hot and dry cold winter
TEMPERATE Warm temperate
TEMPERATE Cool temperate
4
Continued.
Characteristics
Design implication
-Low humidity year round. -High diurnal (day/night) temperature range. -At least two and usually four distinct seasons with low rainfall, very hot summers, cold winters and hot dry winds in summer. With cool to cold dry winds in winter.
-Use passive solar principles with well insulated thermal mass -Maximize night time cooling in summer. -Consider convective (stack) ventilation, which vents rising hot air and draws in cooler air. -Build more compact shaped buildings with good cross ventilation for summer while maximizing solar access, exposure to cooling breezes or cool air drainage, and protection from strong winter (cold) and summer winds. -Use renewable energy sources for auxiliary heating in extreme climates -Use trees, garden ponds and water features to provide evaporative cooling during summers.
-Low diurnal temperature range coast to high diurnal range inland. -Four distinct seasons. Summer and winter can exceed human comfort range. Spring and autumn are ideal for human comfort and mild to cool winters with low humidity. -Hot to very hot summers with moderate humidity.
-Use passive solar principles with well insulated thermal mass. -Minimize external wall areas especially east and west. -Use cross-ventilation and passive cooling in summer as well as convective ventilation. -Allow for solar access, exposure to cooling breezes and protection from cold winds. -Seal thoroughly and use entry airlocks -Avoid auxiliary heating, good design techniques does it all. -Use trees, garden ponds and water features to provide evaporative cooling during summers
-Low humidity. -High diurnal range. -Four distinct seasons. Summer and winter exceed human comfort range -Cold to very cold winters with majority of rainfall. -Hot dry summers. -Variable spring and autumn conditions.
-Use passive solar principles with well insulated high thermal mass. -Maximize north facing walls, especially in living areas with passive solar access. -Minimize south facing windows. -Minimize external wall areas especially east and west. -Use cross-ventilation and passive cooling in summer as well as convective ventilation. -Allow for solar access, exposure to cooling breezes and protection from cold winds. -Seal thoroughly and use entry airlocks -Use renewable energy sources for auxiliary heating in extreme climates.
Utilizing nature in building designs
In the study of nature and design, a vast literature exists. When the two areas are connected, they are mainly referenced under bioclimatic design or vernacular designs with emphasis on basic, good design principles. The Bioclimatic design literature is on the whole more technical and scientific in nature, while Vernacular architecture address issues of culture, tradition and aesthetics as well WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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as comfort. These two vital concepts are important in understanding the basic ideas of a nature integrated design. Table 2: Nature factor Air
Soil
Water
Showing a nature-positive design scheme. Resource
Building fabric
Free air -Natural ventilation -Wind force -Energy content Stack effect -Solar energy, diffuse radiation -Solar energy, direct radiation
Facade and roof -Light weight or massed façade. -Planted surfaces -Rainwater collectors -Day light collectors and Shades -Passive solar absorber -Night cooling by outside air. -Evaporative cooling Construction -Courtyards.
Groundwater -Cold energy -Heat energy Earth/rock -Geothermal cooling -Heat energy
Green zones -Planted surfaces. Ground -Passive solar energy -Passive cooling energy
Lake -Pump water or greywater -Heat/Cold energy River -Pump water or greywater -Heat/Cold energy Sea -Pump water or greywater -Heat/Cold energy
Pure water -Public supply (drinking, cooking) Greywater -Waste water (condenser water, flushing, cleaning) Rainwater -Flushing, cleaning, cooling
Service implication Heat energy -Solar thermal system -Wind energy generator
Natural landscaping services -Permaculture -Pools and ponds
Mains supply. Self supply. -Bore holes
4.1 Resuscitating architecture’s endangered species Recent studies identify the sustainable properties vernacular architecture and vernacular design principles hold in sustainable building. Although most of the original appearance of vernacular architectures disappeared through the renewals since the ideas of new developments in cities and cultures, there is still a lot of building substance that could be rediscovered as old and historic. There are many wonderful building styles from all over the world that can inform us with their shapes, materials, arrangements, decorations, concepts for heating and cooling, etc. Vernacular architecture has been loosing ground over the last couple of centuries, as modern methods prevail. This is unfortunate since many of the old ways employ natural materials and simple concepts that are energy efficient. Also the buildings themselves are often beautiful and enhance simple live styles which are advantageous to the issue of environmental protection and health. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
204 Eco-Architecture: Harmonisation between Architecture and Nature As the basic principles that outline a nature-positive design are all innate in the vernacular design concept, vernacular building design ideas should then be encouraged and improved in order to achieve sustainable and healthy nature integrated designs, making use of the local landscape, local materials, orientation, sustainable techniques of recycling and permaculture, local climate and the conscious idea of balance with nature.
5
Conclusion
Finally, designs that will be produced using this scheme will be identified as modern vernacular type. Its buildings make best use of sun, wind and rainfall to supply energy and water needs of occupants, be it the tropical or African vernacular type or the temperate vernacular architectures. In the case of multistorey that maximizes the land available for green space, the design should be generally Resource Efficient; • Energy Efficiency (sustainably harnessed energy). • Pollution Prevention (including indoor air quality/sustainable material use). • Harmonization with Environment (including ecological integration, bioclimatic considerations and environmental assessment).
References [1] [2] [3] [4] [5] [6] [7] [8] [9]
[10]
Bailey, K.D., Methods of Social Research. The Free Press, Macmillan Publishers, New York, 1982. Berkes, F., Sacred Ecology-Traditional Ecological Knowledge and Resource Management. Taylor & Francis, Philadelphia, 1999. Berkes, F., Kislalioglu, M., Folke, C., Gadgil, M., Exploring the basic ecological unit: ecosystem-like concepts in traditional societies. Ecosystems, pp. 1, 409– 415, 1998. Gadgil, M., Berkes, F., Folke, C., Indigenous knowledge for biodiversity conservation. Ambio, pp. 22, 151– 156, 1993. E. Cofaign, J. Olley, and J. Lewis, The Climatic Dwelling: An introduction to climate-responsive residential architecture, www.jxj.com, London, 1996. Koenigsberger, O., Manual of Tropical Housing and Building Design, Longman Group United Kingdom, 1974. CIBS Guide A2 - Weather and Solar Data, Chartered Institution of Building Services Engineers, London, 1984. Watson, D. and Labs, K., Climatic Design: Energy-efficient Building Principles and Practices, McGraw-Hill, New York, 1983. Hui, S. C. M. and Cheung, K. P., Climatic data for building energy design in Hong Kong and Mainland China, In Proc. of the CIBSE National Conference 1997, 5-7 October 1997, London (paper for CIBSE Virtual Conference) 1997. Energy Design Resources by Architectural Energy Corporation, Boulder, CO., www.energydesignresources.com. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Outdoor residential landscape design in an arid natural conservation area: Bahía de Los Ángeles, México R. Rojas-Caldelas, G. Bojórquez-Morales, A. Luna-León, E. Corona-Zambrano & J. Ochoa-Corrales Faculty of Architecture, Universidad Autónoma de Baja California, México
Abstract The designing of outdoor residential landscapes in a natural conservation area becomes crucial due to the restrictive use of natural resources, disturbance of habitat, and visual impact of man-made buildings. Therefore to integrate architecture and landscape design and to promote a better environment becomes a challenge. This is the reason why this paper focuses on the contributions of landscape design of outdoors in order to achieve sustainable architecture. This project is set in a small coastal rural village known as Bahia de Los Ángeles, municipality of Ensenada in the Mexican state of Baja California, which is located in the Flora and Fauna Natural Conservation Area of Valle de los Cirios, in the Sonoran Desert. Project development deals with four areas of environmental design of the outdoors in arid places: Firstly, the modification of micro climatic conditions. Secondly, the protection of ecological landscape features. Thirdly, the assessment of aesthetic and cultural values of arid landscapes and indigenous flora. Fourthly, the utilization of natural materials for landscaping. Lastly, some conclusions are set confronting the aesthetic and ecological values of deserts against preference of other ecosystems, as well as cultural and economic obstacles faced by sustainable development of rural housing projects. Keywords: sustainable landscape design, landscape architecture, desert garden design, participative landscape design, arid landscape values.
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1
Introduction
Doing sustainable housing projects is not new. There are numerous examples reported in practice as well as in literature. The same can be said with sustainable resource management on issues like water, energy, vegetation, landscape and solid waste among others. Most of the projects are mainly experimental or isolated and work under controlled environments or conditions, but then, a question arises: Is major audience acceptance missing? It could be that many people, theoretically, are in favour of sustainable development and think of it as a good idea for the environment and future generations; however, not all agree that it is a way of life for the present. Unfortunately our society has been conquered by spending and comfort patterns offered by the free market economy, and not many people are able to change. Sustainable development and sustainable architecture remain then as an alternative approach, among others, for making projects. What we are sure of, is that there is a good foundation to build this way to sustainability supported by laws, construction codes, and public policies oriented to make a more efficient use of resources and to develop more friendly environmental technologies. This is what we have found in the housing project for single family household in a rural area in Baja California. Sustainable projects have many obstacles to surpass from the point of view of social acceptance, availability of financial resources for construction and maintenance, ecological constraints on the use of natural resources for building and to merge all of them in a specific time period. Sustainable development also implies an ample competence on various subjects, one of them being the integration of a group of experts that do not necessarily share the same sustainable development framework. So the challenge focuses on a comprehensive proposal capable to integrate sustainable principles in architecture and landscape architecture as a design problem. Therefore this work has a double purpose in mind; on the one hand, to present a sustainable housing project where architecture and outdoor landscape design are integrated, underlying sustainable landscape design and, on the other, to assess the feasibility of sustainable development projects on wildlife protection areas like Valle de los Cirios in México. In a broad sense, sustainable principles are the same when they are applied to landscape or architectural design. They deal with social, economic and ecological factors. Regarding social aspects, they are translated into social and cultural patterns of people, indoor and outdoor use of space, family and social values, aesthetic preferences, education levels, knowledge and management of technologies, interactions between man with the natural and man-made environment and participation in decision-making process. In the second aspect, economic factors are related to employment, income, cost of living, taxes and public or private financial resources for housing or productive programs. Regarding ecological factors, there are natural resources; implying inputs and outputs of materials, energy and information necessary to sustain man, plants and animals. So they provide us with resources for nourishment, clothing, medications, building materials and energy production, but their quality and WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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quantity depend on their resilience. Resource management in both disciplines has tried to address several problems such as conservation on the long-term scenario or strategic approach; reduction, reuse and recycle of materials and energy within a system; and rational and efficient use of resources and the mitigation of environmental impacts.
2 Methodology The housing project was designed keeping in mind that it is located in an extreme arid region, where it is crucial to manage scarce water resources, in aspects such as: temperature, wind, humidity, rainfall and underground water, as well as energy generation by solar and wind technologies. Another critical resource to preserve is biodiversity and landscape character, due to the fact that the site resides in a wildlife reserve containing ecosystems with high fragility index. The extraction of materials for building or mining is also restricted to certain places as well as the use of soft technologies. All of these shortcomings have demanded a project that mostly relies on the use of climatic passive principles for indoor and outdoor design spaces. Outdoor landscape design has also implied work over the concept of xeroscape Weinstein [1]. That is, centred in a wise management of available water resources, to promote the use of native plants to enhance biodiversity and the beauty of forms and colours of arid ecosystems. Native plants have suitable attributes compared to those induced plants; among them are their resistance to climatic stress, long periods of drought, high winds, control of soil erosion and their tolerance to salinity. The purpose of all of them is to reduce, reuse and recycle water, energy and materials, avoid disturbance of natural ecosystems and reduction of visual and aesthetic impacts over the landscape. This paper underlines landscape contributions to architectural design in two stages: in the first one, it has been taken into account a description of regional landscape features to understand its physical nature and aesthetical values, as well as the essence to preserve its character, aspects that have been taken as inputs for outdoor design. In the second stage, there has been an interest to design a microenvironment around the house, considering the fundamentals of bioclimatic design and xeroscape. Achieving micro climatic adaptation of places has been done though the use of plants and other materials to provide shading over vertical and horizontal surfaces, as well as filtration or reduction of light over transitional places and wind management. Ecologically, a minimum removal of natural vegetation and topographic changes was proposed in order to preserve landscape features. Besides, native plants of the region for gardening were used and some of them were relocated on the terrain. Their use was thought to contribute towards minimizing water consumption and erosion. Aesthetically, spaces were designed integrating attributes such as: form, colour, texture, and diversity of plants; complementing the cultural preferences of the household in relation to scale and proportion of spaces, views, and significance of landscape marks. Natural elements, such as sand, gravel, pebbles, rocks, shells, and dead
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208 Eco-Architecture: Harmonisation between Architecture and Nature woods, were selected as materials for landscape purposes of pavement, fences, and partial shadings, depending on their availability in the region.
3
Results
Bahía de Los Ángeles is a small coastal town fig. 1with a population of about 698 inhabitants INEGI [2], located by the Sea of Cortez in Baja California, Mexico (28o 55’ north latitude and 113o 36’ west longitude). It also belongs to the Sonoran desert region and it is immersed in a flora and fauna wildlife reserve called Valle de los Cirios. The reserve is characterized by dominant and gigantic plant species: Pachycereus pringlei (Cardon) and Fouquieria columnaris (Cirio), and in addition, there are other 56 endemic plant species, 67 types of mammals, 86 types of birds and 52 types of snakes and lizards CONANP [3]. The climate has been considered among the hottest and driest places in the world, with an annual average rainfall of 40.4 mm, with summer temperatures above 45o C and under 5o C in winter. Evapotranspiration varies annually from 600 to 1200 mm. There are just a few watercourses, most of them are dry all year long, and main water sources are underground. In town, there is a spring with a limited capacity not enough to cater the needs of the population. In order to cover the deficit, water is brought by a pipeline coming from Agua Amarga, a subterranean reservoir located 30 km away. Water extraction is controlled by the National Water Commission CONANP-UABC [4]. Thus, water is a limitation to population growth and promotion of economic activities. However, there is always the chance to desalinate seawater to improve those conditions. The region has an enormous solar potential for energy production and a moderate one for wind. Actually, energy is partially provided by a diesel plant that works around 12 hours a day. Some people in town have solar panels to cover the daily deficit, but low-income households do not. 3.1 Landscape assessment Sometimes in landscape assessment in wildlife areas, the ecological values are prioritized over cultural and aesthetic aspects, this project tries to establish a balance between those aspects. This is why; this section deals with the being-atthe-desert experience, as an important input for design. Valle de los Cirios is characterized by bare plains and gentle slopes; landscapes contrasting the blue, clean and bright skies; prevailing horizontal planes over vertical ones, and creating an atmosphere of infinite open space, unprotected, profound and distant from civilization. Vertical elements like hills and mountains have been developed as landmarks over the landscape, as well as green patches of desert trees and shrubs, showing the impact of dampness on the air or the existence of subterranean water. At plain sight, vegetation seems to be quite monotonous, mainly composed of small shrubs in shades of grey, usually with thorns and in low density; communicating the idea of dryness, thus, creating a distorted illusion associated to sensations of high temperatures and sandy soils. Contrary to this idea of poverty and lack of diversity, the desert has an outstanding beauty WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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and a rich hidden world of living plants, animals and cultural heritage such as cave paintings that most of the time are not apparent at plain sight. Richness is present in small areas within great regions: in coastal beaches, small water springs, canyons, creeks and valleys, most of them are places of great biodiversity, where grasses, cactus and trees are the tallest. Colours, textures and forms are unusual and in a scale of monumental proportions. Therefore, deserts have a natural order and aesthetic values that have to be discovered and understood by foreigners in order to design and preserve the environment.
Figure 1: Aerial view of Bahía de Los Ángeles
Figure 2: Site project and surrounding views to the mountains, sea and islands 3.2 Site Bahía de Los Ángeles is a protected bay, surrounded by small mountain ridges, full of contrasts in colours and textures. The bay is a quiet and silent pond with great views to the islands of the Sea of Cortez fig. 2. The site is located over a moderate slope, full of big pieces of granite rocks, surrounded by two small creeks, streaming down from the top of the alluvial fan, limiting the North and South sides of the plot of land. Compared to other places in town, there are many desert plants and grasses like small size Pachycereus pringlei, Opuntia sp., Fouquieria peninsularis, Bursera microphylla, Lophocereus schotti, Cercidium microphyllum, Olneya tesota, Encelia farinosa, Ferocactus, Pedilanthus macrocarpus, Agave desertii, Larrea tridentata, Simondsia chinensis, Ambrosia dumosa INEGI [5] all of them useful for gardening. The natural conditions of WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
210 Eco-Architecture: Harmonisation between Architecture and Nature the terrain have offered us resources for design. The project has been developed over terraces with nice views to the bay, mountains and islands. Creeks were preserved and integrated as natural borders of the plot of land in order to allow the water to flow down during the rainy season. In addition, some rocks were pilled to enclose the backyard and others were put in small groups making ornamental islands over the terrain. 3.3 Household The household consists of a young couple with a dog and no children, and both are very concerned about preservation of the environment because their daily living depends on it. Roberto is a fisherman and usually goes sailing in the Sea of Cortez. Sometimes, he is hired as a tourist guide or by marine researchers, supporting them in reconnaissance surveys of whales, dolphins, whale sharks and sea turtles. Isabel is a biologist working for the Secretariat of Environment and Natural Resources in Bahía de Los Ángeles, where she is responsible of safeguarding natural resources of the islands of the Sea of Cortez. As we have seen, both share the same environmental interests and they are active people involved in many community activities to improve their own town. Their background was relevant to us because they were sensitive to accept the design of an alternative housing project, understanding that the construction would be progressive or in stages because of the lack of financial resources to do it in a short period of time. The land belongs to Roberto and they would like to have a house open to the views of the bay, mountains and islands, but at the same time they want to feel protected from the outside. Both have agreed to have native plants for gardening in order to satisfy aesthetic and medicinal values and the use of local materials. In addition, they would like to have a terrace in the upper floor for multiple uses such as a place to sleep outside in summer protected from any kind of animals, or as a place to rest or entertain friends and relatives. Roberto also needs a place where he can clean and fillet fish and a parking space for his pickup truck and the boat. 3.4 Design criteria Outdoor design is going to have slight perimeter limits to allow visual contact with landscape, taking advantage of creeks, small size shrubs, fences and trees. There are two types of views to be promoted: close and distant, the first one has to be rich in forms, colours and textures. The second one has to capture natural landscapes from around the site. Transitional areas are designed as a way for passing from sunny to shaded spaces. Architectural design is going to be organized around a patio concept, taken from Mexican colonial houses. Architectural design is based on low energy passive strategies and the use of solar panels for water heating and energy production. Shades from volumes, man made shades and trees are also important in the provision of comfortable open spaces. Recycled water is going to be used for gardening. There will be a place to dispose organic waste. Criteria that has been applied in the housing project fig. 3, 4 and table 1. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Figure 3: Garden layout; 1 backdoor entrance, 2 contemplative patio, 3 contemplative landscape views, 4 Indoor patio, 5 ornamental main entrance.
South-East Façade
North-East Façade Figure 4: Façades showing plant arrangement of landscape outdoors with native plants.
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212 Eco-Architecture: Harmonisation between Architecture and Nature Table 1: Space function
and
Environmental functions of landscape elements. Vegetation
1. Patio Back door entrance, transitional space for clothesline 2.Contemplative patio from the studio
3. Contemplative views from kitchen, dinning and living room
Creation of a microclimatic space: shaded by trees over the west façade: rich in textures, forms and colours: Cercidium microphyllum, Prosopis glandulosa, Lophocereus schotti Machaerocereus gummosus, Simmondsia chinensis, different cactus species and rocks Island arrangements made with desert plants, rocks and annual flowers (Abronia villosa, Eschscholtzia mexicana, Beloperone californica , Encelia farinose).
4. Indoor patio: Contemplative Shaded Ventilation Natural lightning 5. Main entrance, ornamental
One side is limited by a line of Agave desertii, Opuntia violacea, Opuntia cholla. and Burcera microphyla. On the other side Burcera microphyla, Fouquieria columnaris and splendens, Pachycereus pringlei, Opuntia fulgida, Opuntia englemanni, Pedilanthus macrocarpus and different cactus species
Porch, transitional space, as an outside living room in summer
Parking space for the pickup truck and the boat
Perimetral fence made of living sticks of Fouquieria splendens
Pavements
Furniture and Utilities
Pebbles
Partial horizontal shading made of cardon dead woods clothesline. Rocks Slope driven to the centre of space to capture rainfall
Wood and compacted sand
Specific spots of sand, gravel and wood
Slope driven to the centre of the plot to capture rainfall
Wood, squares of pebbles and compacted sand
Small fountain as a water reservoir Big size rocks Recycled water Recycled water and Slope driven to the centre of space to capture rainfall
Pathway to the entrance, sand and wood.
Partial horizontal shading made of cardon dead woods Small walls made of sand sacs plastered with cement and some outdoor furniture or a hammock. Partial horizontal shading made of cardon dead wood
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Compacted sand and wood
Levelled and compacted soil
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Discussion
At the beginning of the project we were very enthusiastic trying to make a sustainable housing project and it was easy to do it on paper and maybe as experimental work; but our doubts began when someone asked us what could happen if a major demand of this prototype or any other in this community were requested. We would face the problem of environmental destruction, which would be critical in a natural protected area such as this one. That has made us think about other questions that need to be answered in order to promote sustainable buildings in this kind of areas: 1. People are conscious about the value of natural resources and cultural heritage for preservation purposes. They also look at sustainable development as a tool for improving their quality of life, but they disagree with the great amount of regulations and the high cost they represent, like permits and licences. That means that only wealthy households will be able to comply with the requirements. 2. Many people in Bahía de Los Ángeles agreed that sustainable development is a good thing for the environment and future generations, but they see this proposal far from their own reality because they are low income households, as the young couple that we have been working with. 3. Housing projects for low-income people in Mexico have to be seen as life projects to be built up in stages though a long period of time. Therefore, sustainable projects are not feasible for short term completion. 4. Wildlife protected areas have many regulations over the use of resources; in fact, it is easier to import technology, materials, and even labour force to build a project or to live in a mobile home like many retired Americans do. That has resulted in a negative visual impact, in creating pollution, and in a lack of identity with local architecture, culture, and landscape, instead of promoting endogenous development with ad hoc technologies, using local materials and labour force. 5. Sustainable houses will demand materials such as wood for building and shading; rocks, sand, gravel, insulation sheets, pipes, steel, and water reduction accessories; solar and wind technologies for energy production, water heating, water desalination, and water pumping accessories; safe disposal of batteries; specialized labour force; water treatment plants; and native plants production in nurseries for gardening. Therefore, it is necessary to promote the creation of “green enterprises” oriented to cater local needs to contribute to local development. 6. It is impossible to achieve comfort with passive design strategies in extreme climatic regions; thus it is necessary to use active systems for cooling. Natural landscapes are valuable resources for most of people and therefore they have a positive attitude towards them, such as forests, mountains, lakes, rivers, and beaches. However, for the layman, WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
214 Eco-Architecture: Harmonisation between Architecture and Nature deserts are considered terrible places to visit because not everyone likes being hot, dry, full of dust, and might consider them dangerous and without trees. This is a negative cultural image that has been created over the years about deserts, when deserts are just simply different ecosystems with other aesthetical values.
5
Conclusions
Despite the fact that there are people able to put into practice sustainable development, there are short term obstacles, such as financial constraints and regulations. Therefore, sustainable projects have to be seen as projects with a series of stages to be completed in a long term plan. When projects are designed integrally and in a collaborative way, they have better environmental responses, but this is not enough to get them to work. Sustainable development projects are much more than making a simple design because it implies deep changes in cultural patterns of spending, clean production, and the development of local community capacities and technology.
References [1] Weinstein, Gayle (1999). Xeriscape handbook: a how-to guide to natural resource-wise gardening, Fulcrum Publishing, p 142. [2] INEGI (2001). XII Censo de población y vivienda 2000, Instituto Nacional de Estadística, Geografía e Informática, México. [3] CONANP (2003). Programa de Conservación y Manejo del Área de Protección de Flora y Fauna Valle de los Cirios, borrador de trabajo, http://www.conanp.gob.mx/anp/cirios/PCM_VC_270803A.doc [4] CONANP-UABC (2004). Diseño participativo de una estrategia de desarrollo rural sustentable para la comunidad de Bahía de Los Ángeles, Baja California, México, informe técnico presentado a la Comisión Nacional de Áreas Naturales Protegidas-SEMARNAT, p. 182. [5] INEGI (2001). Síntesis de Información Geográfica del Estado de Baja California, Instituto Nacional de Estadística, Geografía e Informática, México.
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The house by the lake C. A. Brebbia1 & J. Gorst2 1 2
Wessex Institute of Technology, UK James Gorst Architects, UK
Abstract This paper describes the proposed building of an Ecohouse located alongside a small lake and against a steep slope. Managed woodland surrounds the site, which is accessed by existing driveways. The design of the landscape accepts the land in this existing state and does not propose any formal area requiring additional work. The whole design is in harmony with its surroundings. The philosophy of the design is to produce a low energy eco-friendly house which is as environmentally aware as it is architecturally distinguished. As such, it will serve as an example for the country house of the 21st century.
1
Introduction
The brief was to design a house for the first author and his wife that responds to his academic needs as well as being a functional home. It is also a statement of their commitment to creating a type of architecture which is environmentally friendly and in harmony with its surroundings. The shared objective of the team was to design and build a low-energy, sustainable home of distinguished architecture [1]. James Gorst Architects led the team which included the eminent environmental engineer, Max Fordham, ecologists and landscape architects, as well as consulting engineers and planners. Their aim was to design an ecofriendly house which can be a model for the future. This paper describes the main aspects of the new design, i.e.: •
The Design Guidelines: How the proposed site is ideally situated to the design of an eco-house and how the proposal relates to the new UK Planning Policy guidelines known as PPS7.
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216 Eco-Architecture: Harmonisation between Architecture and Nature • • •
The Design Philosophy: Setting up the requirements of the owners and in particular, their commitment to commission an eco-friendly house. Environmental Engineering: The guideline was to produce an energy efficient building that can achieve a carbon neutral rating and consume as little energy as possible from non-renewable sources. The Structure: The aim was to design a light structure with minimum impact on its environment. The contractor was to use vernacular materials.
The proposal, which has recently been rejected by the New Forest planners, is now under appeal and it is hoped that the Inspector in charge of the hearing will exhibit a more open-minded attitude to this important project.
2
The design guidelines
The house would be built in part of the nearly 20 hectares surrounding the existing Burley Hill House. The land is located on high ground and consists of mature woodlands. Burley Hill House is sited north-west of Burley, a popular and picturesque village in the heart of the New Forest. The site of the proposed new house is an existing clearing in the deciduous woodland. The clearing is located on a south east facing slope some 15m below Burley Hill House and 15m in height above the centre of Burley village. The clearing contains a small lake on a leveled area within the overall slope, and is open-style grassland. The whole land has been improved under the supervision of The Forestry Commission. All woodlands at Burley Hill are managed in accordance with the plan of operations approved by The Commission. This includes thinning, replanting, species selection, habitat, diversification and management of all rides. The Burley Hill estate lies within the settlement of Burley and is included within that conservation area. The village centre, with its full range of facilities and shops is only 700m away. Thus, for an isolated house, the need to travel is much less than for the case of other country houses. Planning permission was sought within the guidelines of the Special Planning Policy called PPS7, published in 2004. PPS7 encourages innovative design and its paragraph II summarizes the terms that need to be applied to any project. i.e.: • • • • • •
Single house. Isolated location. Exceptional quality of design and engineering. Innovative and groundbreaking in design, materials and methods of construction, as well as in protection and enhancement of the environment. Significantly enhances the immediate setting. Sensitivity to the characteristics of local areas.
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Eco-Architecture: Harmonisation between Architecture and Nature
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Burley Hill House, east view. Figure 1:
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218 Eco-Architecture: Harmonisation between Architecture and Nature
Figure 2:
3
Interior view.
The design philosophy
The owners of the proposed house required suitable accommodation for an academic and his wife as well as visiting family and guests. The brief was to develop a design in harmony with its environment in order to make a statement and point out a way towards a sustainable future. Hence the house is a demonstration of the commitment of the occupier to environmental and ecological issues [2]. Throughout the design, the environmental requirements are dominant. The house sits lightly on the land, not cutting into the slopes or scarring the terrain. Its construction exploits the vernacular of the New Forest, cob walls with clay extracted from the site, locally sourced timber for the structure and for cladding the facades. The philosophy of a low energy, lightweight, bioretrogradable and demountable building means that the use of concrete has been excluded from the design. The complex facetted roof is covered in an eco-friendly recyclable membrane and dangerous chemicals have been avoided throughout the design. The structure of the scheme has been developed by Alan Baxter Associates Consulting Engineers and the environmental strategy with Max Fordham, both eminent consultants. Similarly, the ecological aspect of the building has been assessed by Ecohomes Scheme [3] and the landscaping proposal set up by Hilary Martin of Integrated Design.
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Upper level plan. Figure 3:
220 Eco-Architecture: Harmonisation between Architecture and Nature The design of the house presents ample space for well-lit offices and a library. Particular attention has been paid to the orientation of the rooms in order to maximize solar heating and ventilation.
4
Environmental engineering
The design proposal by Max Fordham was to produce an ecology-efficient building. Their prime concern was to achieve a low energy building by reducing energy delivery inefficiencies. To this end they have proposed: • • • • • •
To avoid gas and oil-fired heating through super insulation and maximizing useful solar gain. To avoid the need for space cooling through careful consideration of building orientation, fabric design and effective natural ventilation. Generate sufficient electricity on site from photovoltaic cells to meet the demands of the building. Generate solar-heated hot water from roof-mounted panels. To use rainwater for WC flushing to minimize potable water consumption. To treat wastewater on site as far as practicable.
4.1 Temperature control in the winter The house is expected to have a heat loss in the order of 20,000kWh/annum. The majority of the space heating will be provided through useful solar gains (approximately 16,000kWh/annum over the South and South West orientations). Heat gains from occupants (in the order of 1,000kWh/annum) and other internal gains from white goods etc. (in the order of 2,500kWh/annum). In extreme weather conditions, some supplementary heating may be required. In order to avoid gas or oil-fired heating, which would directly produce CO2 and NOx as well as requiring significant infrastructure to the site, the use of a Ground Source Heat Pump (GSHP) is preferred. A properly designed GSHP installation would be expected to produce approximately half of the CO2 emissions of a similar gas-fired, condensing boiler. A typical Coefficient of Performance (COP) is 3 to 4 meaning that for a 2.5kW electrical input, 7.5–10kW of heat energy is produced. This is compared to a best COP of 0.9 for a gas-fired boiler. Electrical energy used to power the heat pump will be offset by that generated on-site by the photovoltaic cells. The heat pump works on the principle of moving heat energy from a heat source to a heat sink, it being more efficient to transfer existing heat energy than to generate new.
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Lower level plan. Figure 4:
222 Eco-Architecture: Harmonisation between Architecture and Nature A refrigeration circuit in the heat pump transfers low grade heat at the ‘source’ (typically 5–10o C) to a higher grade heat (typically 35–45oC) for use in the heat ‘sink’. In the case of the Burley Hill House, the heat ‘source’ will be the lake and the ‘sink’, the house. By using the lake, the ground source heat pump efficiency is increased since ground with a high moisture content offers superior heat transfer. Pipework loops will be installed on the bottom of the lake meaning they can be easily removed if decommissioning the house. As the lake has an approximate volume of 600m3, the heat pump is of insufficient size to alter the temperature of the water significantly. GSHP installations operate best with underfloor heating installations, since the water temperatures are far lower than those used in traditional ‘radiator’ systems. Underfloor systems also offer the advantage of heating the surfaces, rather than the air above the occupied zone, offering a reduction in heat input requirements. Underfloor heating will be installed throughout the building, but its use is expected to be minimal. Wood stoves located within communal living areas will provide a focal point to the room. They will also offer a carbon neutral method of heating as the fuel will be supplied from the woodland trimmings from the surrounding estate, as part of the existing forestry maintenance scheme. Furthermore, by specifying units with integral heat exchangers, we plan to preheat the domestic hot water installations when the stoves are in use. Space temperature control will be optimized by an intelligent Building Energy Management System (BEMS) which will include weather compensation, optimum start/stop and night/holiday set back. Guest rooms will be maintained at 12oC when not in use through winter to prevent condensation. The BEMS will ensure that useful solar and internal heat gains are maximized before operating the heat pump. 4.2 Temperature control in the summer The architectural design ensures that the building form does not cause uncomfortable summer time temperatures, a problem which is becoming more common with modern building construction. A shadowing strategy has been adopted to cut out the direct radiant component of the higher summer sun. Shading has been carefully designed so that whilst it avoids solar gain during the summer, it does not prohibit useful solar gain when the sun is at a lower altitude during the winter months. We anticipate that the surrounding deciduous trees will also help in this respect. High performance glazing will be installed to further reduce heat gains to the space from diffuse solar radiation. Ventilation will play a key part in maintaining a comfortable summer environment. Passive stack ventilation will be employed where a useful height differential exists to exploit the properties of warm, buoyant air. Elsewhere, the window design will offer sufficient area for good single-sided or cross flow ventilation of rooms. Generally, natural ventilation of all rooms will be encouraged, however where activities resulting in high moisture output take place (such as shower rooms and WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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the kitchen) supplementary rapid extraction will be provided. In these locations, fans will operate on a humidity sensor to minimize operating time. 4.3 Generation of electricity Although renewable wind technologies offer the potential to produce greater quantities of electrical energy, they would not be appropriate in this particular location. The visual appearance and the impact on the local environment would not be in keeping with the ethos of this project. Therefore, solar photovoltaic panels were selected to generate on-site energy. Approximately 22m2 of photovoltaic cells will be installed on the roof of Burley Hill House, the orientation and mounting angle selected in order to optimize solar gain. We anticipate the solar panels will generate a peak output of 2kW giving an annual output in the order of 1,650kWh, which is the estimated annual demand for the house. This will save 710kg of CO2 when compared to the same quantity of electrical energy supplied from the national grid, and effectively make the house carbon neutral. When energy generation exceeds demand in the summer, electricity will be sold back to the grid, using the grid as a ‘battery’ for times of little or no sun and when artificial lighting is required at night. In order to facilitate this, an electrical supply is unavoidable. The cable route will be carefully traced to avoid disturbance to the local environment as far as possible. Natural daylight will be maximized throughout the building in order to reduce the reliance of the occupants on artificial lighting. Low-energy light fittings will be selected throughout, with appropriate control strategies employed to avoid unnecessary use. 4.4 Solar hot water heating Roof-mounted, high efficiency solar water heating panels will be installed in order to provide domestic hot water to the house. During the summer, all of the hot water requirements of showering etc. will easily be met by the solar panels. When the sky is overcast, some solar radiation will still be present and this will be used to ‘pre-heat’ the hot water cylinder. Further water heating will be provided by the wood-fired stoves when they are in use. By installing 2m2 of solar panels, 2,000kWh of heat output per annum will be produced, representing over 50% of the hot water requirement. 4.5 Water conservation Rainwater harvesting and storage will be provided to flush all WCs. On average, a typical two-person dwelling consumes over 28,000 litres of water per year, just to flush WC pans. Preliminary calculations suggest we could collect over 100,000 litres of rain per year, negating the need to flush potable water through a toilet. It may be possible to investigate using spring water for drinking purposes. At present, a mains supply will be required. However, low flow fittings will be WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
224 Eco-Architecture: Harmonisation between Architecture and Nature specified throughout to reduce demand, and as stated above, mains water will not normally be used to flush WCs. 4.6 Waste water Because of the isolated location, there are no public sewers to which we could discharge sewage and waste water. Common practice is to either provide a cesspit (which requires frequent emptying by road tanker) or by septic tank coupled with a soak away. As the soil type is predominately clay, a drainage soak away is not feasible. Sewage treatment will be provided on site by coupling a septic tank with a purpose made, horizontal reed bed. In this way, waste water can be treated to a safe level, allowing it to be discharged into the lake after passing through the reed bed. Reed bed installations are increasingly common and provide a natural means of treating water, reducing the burden on sewage treatment plants. Although the septic tank will require de-sludging on a four year basis, the environmental impact of such a scheme is small. Natural evaporation of the lake should regulate its level throughout the year. However, sometimes it ‘overflows’ to a drainage ditch, which in turn, discharges into a local river. Dialogue has been established with the local offices of the Environment Agency to ensure the compliance of the scheme.
5
The structure
The proposed new building will be of lightweight construction with a timber frame. It is therefore, planned that the foundations will need to support point loads from the posts in the timber frame. The key factors influencing the design of the foundations were the need to minimize construction in the ground, the desire to avoid using concrete, the relatively light point loads to be supported and the nature of the ground. The Structural Engineers proposed the use of galvanized steel screw piles to respond to all these concerns. These comprise steel augers which are screwed into the ground to a depth determined by detailed consideration of the soil properties. The principle is similar to that by which in-situ concrete piles are formed, except that the auger is not extracted and replaced with concrete. The auger is left in the ground and the loads from the new structure are applied to the shaft of the auger once the machinery for screwing it into the ground has been removed. It is possible to remove the piles by simply reversing the machinery and unscrewing them. The selection of a diameter and working length for a pile is a matter for the detailed design stage, but is it expected that screws with a diameter of 200–300mm will be selected. The impact on the ground is minimal. The piles are conventionally installed with rotating machinery that is attached to the back-acter of a light wheeled tractor. The whole system has been used successfully elsewhere in environmentally sensitive situations. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Conclusions
This paper describes the design for an eco-house put forward by James Gorst Architects on behalf of the owner of the site, Professor Carlos Brebbia, both co-authors of this paper. The brief was to design an outstanding piece of architecture that satisfies the requirements of the owner. Equally important was, for the building to be energy efficient and to harmonize with its environment. The proposed design has been the result of a team effort involving planning consultants, landscape architects, ecologists, environmental and structural engineers as well as the architect himself. Close collaboration between the different partners as well as the owner was required to achieve all the requirements. The authors believe that an optimal solution has been found of outstanding architectural and engineering merit. Designs like this are essential to point the way to the future.
Acknowledgements The authors would like to acknowledge the contributions of other members of the design team, in particular: Hilary Martin, Landscape Architect. Ian Smith, of Max Fordham LLP. Chris Corcoran, Southern Planning Practice Ltd. Robert Bowler of Alex Baxters and Associates. Their close collaboration with James Gorst Architects has resulted in the design described in this paper.
References [1] [2] [3] [4] [5]
McCloud, K “Grand Designs Abroad. Building your team.” Collins, London, 2004. Roaf, S. “Closing the Loop. Benchmarks for Sustainable Buildings”. RIBA Enterprises, London 2004. Ecohomes Scheme, British Research Establishment, Watford, 2005. Wilhide, I., 'Eco' Quadrille Publishing, London, 2002. Roaf, S., 'Ecohouse 2: A Design Guide' Elsevier, Amsterdam, 2003.
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Indicators for the ecological planning of buildings C. Seyler, C. Stoy, I. Lützelschwab & S. Kytzia Department of Civil, Environmental and Geomatic Engineering, Swiss Federal Institute of Technology Zurich, Switzerland
Abstract Until now, ecological assessments of buildings have been focussing on the use phase, such as the consumption of operating energy or the emission of in-house pollutants. So far, little emphasis has been placed on the construction and disposal phase of buildings. As the use phase is getting more and more optimised, environmental impacts caused by the construction phase are gaining in importance. To optimise the ecological performance of a building information is needed in the early design phases when there is still a wide scope for decision. This paper presents a method, based on cumulative energy indicators, which allows assessing the environmental impacts of a building when only a little information is known. Keywords: life cycle, indicator, early design phase, building material, environmental impact assessment.
1
Introduction
In the last years the main focus of environmentally friendly buildings has been laying on the use phase. Large efforts have been put, e.g., on the optimisation of operation energy and the prevention of indoor pollutant emission. Those environmental impacts have become more and more optimised, e.g., by using better insulation, the use of energy saving machines or by the substitution of critical materials in housing spaces. As a result, the other phases in the building’s life cycle, such as the construction phase or the disposal phase, have gained in importance. Recent LCA studies have clearly shown a shift of the main environmental impacts from the use phase towards the construction phase for WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060231
228 Eco-Architecture: Harmonisation between Architecture and Nature ecologically optimised buildings [1]. Thus, to get further environmental improvements in a building’s performance planners and architects should now concentrate on the construction phase. To include the environmental impacts of the construction phase in the planning of a building several instruments have been developed in the Germanspeaking region in the last years, e.g. [2, 3, 4, 5]. Those instruments are used in different planning and design stages and they require information on different levels of detail. Of special interest are instruments which can be used in an early design phase as they allow for decisions at a stage when there is still a wide scope for decisions. Such instruments exist, but they usually work on a qualitative basis, e.g., on checklist or recommendations [4, 5]. No method which allows for a quantitative assessment of the environmental impacts of buildings in early design stages exists today. We have developed an instrument which can be used for a quantitative estimation of the environmental impacts of the construction phase of a building in early design stages. Our method works in analogue to the principle of quantitative cost estimation of buildings in early design phases [6, 7]. We provide indicators which base on the cumulative energy demand of the material composition of the building. Those indicators are derived from reference buildings and are listed in a reference building catalogue. To make an environmental assessment of a building, a reference building from the catalogue is chosen and the corresponding indicators are multiplied with reference quantities of the building under study such as the gross floor area or the gross volume. Cumulative energy demand as a measure for the environmental impact is chosen because it is known to architects and because it allows for a direct comparison with other energy consumptions of the building, e.g., the operating energy. In this paper we present how our cumulative energy indicators are calculated from reference buildings and how they are applied.
2 Calculating the cumulative energy indicators 2.1 Method: from accounting documents to indicators The cumulative energy indicators are developed in analogue to economic indicators which are used for estimation of building construction costs in early design phases [6, 7]. Figure 1 shows the proceeding for developing such indicators. The basis for calculating the indicators are accounting documents of already existing buildings. Those accounting documents, which contain information on the building process, the type and dimensions of the materials used and the arising costs, are evaluated systematically. First, every documented work is assigned to an element group according to the standard for cost calculation [8, 9]. The standard for cost calculation classifies the costs of all works of a building into different cost groups. The classification bases on the different components and parts of a building (so-called element groups) and can be done on different levels.
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Accounting Accounting documents of documents of existing buildings existing buildings
Planning Planning documents ofdocuments buildings of buildings
Accounting Accounting documents of documents of existing buildings existing buildings
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Planning Planning documents ofdocuments buildings of buildings
Conversion ofConversion building of building process process information information into material into material information information
Calculation ofCalculation material ofmass material mass
Linking of Linking of materials materials with with environenvironmental mental assessment assessment method method
Assignment Assignment of works works to of element to element group group
Aggregation Aggregation of costs of costs within within element element group group
Assignment Assignment of works works to of element to element group group
Determination Determination of areas/ of areas/ volumes volumes
Economic indicators Economic per referenceindicators quantity per reference quantity
Figure 1:
Aggregation Aggregation of environof environmental mental impacts impacts within within Element Element group group
Determination Determination of areas/ of areas/ volumes volumes
Cumulative energy indicators Cumulative energy indicators per reference quantity per reference quantity
Scheme of the proceeding for calculating economic indicators (left hand side) and ecological indicators (right hand side).
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230 Eco-Architecture: Harmonisation between Architecture and Nature For calculating the indicators, for example a work such as „putting down and compressing of a gravel layer“ would be assigned to the element group “foundations”. In the next step, all arising costs (or environmental impacts for the ecological indicators) within one element group are summed up to yield the total costs per element group. Such an aggregation can be done on different building levels according to the standard for cost calculation. In parallel, the reference quantities such as areas or volumes of the element groups are determined from the planning documents [10]. Such reference quantities are, e.g., the external wall area or the excavation volume. In the last step the aggregated costs (or environmental impacts) are divided by their belonging reference quantity. The result is an indicator which indicates how much, e.g., 1 m2 of external wall area costs. For calculating ecological indicators, the information from the accounting documents has first to be converted into ecological relevant information (see Figure 1, grey arrows on right hand side). This is done by first converting the information on the building process into information on the building material. E.g., information such as “putting down and compressing of a gravel layer” is converted into the material information “gravel”. Or the building process information “installation of boarding panel with timber framework” is assigned to the material “wood”. In the next step the mass of the materials is calculated. Usually enough information on the dimension of the building components can be found in the accounting documents. Together with the material density, which is taken from literature, the mass of the used material can be calculated. When the material masses are known, they can be linked with an environmental impact assessment method. In principal, any assessment method can be chosen, e.g., the Eco-indicator 99 [11] or CO2-equivalents [12]. For the reason explained above, we chose the cumulative energy demand as assessment method [13]. Values for the specific cumulative energy demand for different building materials can be taken from literature or electronic databases. As our indicators have been calculated for Switzerland, values have been taken from Swiss literature [14]. By multiplying the material mass with its specific environmental impact, the total environmental impact of a building component can be calculated. Taking the gravel example from above and considering a surface of the gravel layer of 190 m2 and a thickness of 15 cm, the mass amounts to 51300 kg (assuming a gravel density of 1800 kg/m3). By liking the mass to the specific cumulative energy demand of gravel, which is 0.03 kWh/kg, the cumulative energy demand of the gravel layer is calculated to be 1540 kWh. Then, again, this ecological information is assigned to the element group according to the standard for cost calculation and aggregated within this element group. At the end, these aggregated values are divided by their belonging reference quantity. The results are cumulative energy indicators per, e.g., m2 of external wall area or m2 of gross floor area of the reference building. 2.2 Results: cumulative energy indicators for 20 buildings Until now, 20 buildings have been evaluated and cumulative energy indicators have been calculated [15]. Two indicators are provided on the level of the overall WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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building, one based on the gross floor area and one based on the gross volume of the building. A second set of indicators have been calculated on the level of socalled macro elements. On the macro level a building is divided into large element groups such as foundation, external walls, internal walls, floors and ceilings, roofs [8]. These are element groups which are very appropriate for the use of indicators as their approximate measures are known already in early design stages [1]. Note that the service installations have not been included in our survey although they usually have a large contribution to the ecological performance of a building. The indicators on the macro level refer to the reference quantity according to the standard for cost calculation, e.g., the external wall area [10]. In Figure 2 the cumulative energy indicators for two examples are shown.
Apartment building (6 apartments)
Office building
Type: Year of construction: Gross floor area: Gross volume:
Type: Year of construction: Gross floor area: Gross volume:
Brickwork building 1995 904 m2 2685 m3
Cumulative energy indicators:
Steel structure 1995 7345 m2 26073 m3
Cumulative energy indicators:
Gross floor area: Gross volume:
718 kWh/m2 GFA 242 kWh/m3 GV
Gross floor area: Gross volume:
1221 kWh/m2 GFA 344 kWh/m3 GV
Foundations: External walls: Internal walls: Floors and ceilings: Roofs:
435 kWh/m2 FA 266 kWh/m2 EWA 99 kWh/m2 IWA 285 kWh/m2 FCA 245 kWh/m2 RA
Foundations: External walls: Internal walls: Floors and ceilings: Roofs:
1443 kWh/m2 FA 572 kWh/m2 EWA 231 kWh/m2 IWA 382 kWh/m2 FCA 625 kWh/m2 RA
Figure 2:
Cumulative energy indicators for an apartment building and an office building. GFA: Gross floor area of building, GV: Gross volume of building, FA: Area of foundation, EWA: External wall area, IWA: Internal wall area, FCA: Floor and ceiling area, RA: Roof area.
The first example is an apartment building constructed in brickwork. The house has a gross floor area of 904 m2 and a gross volume of 2685 m3. The calculated cumulative energy indicator based on the gross floor area amounts to 718 kWh/m2, the one basing on the gross volume amounts to 242 kWh/m2. Compared with the building on the right hand side, which is an office building in steel structure, it can be seen that the indicators for the apartment house are WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
232 Eco-Architecture: Harmonisation between Architecture and Nature lower. This means that the specific environmental impact (per m2 gross floor area or m3 gross volume) is lower than for the office building. The second set of indicators is the one for the macro elements. For the apartment building it’s the foundation which has the highest impact per reference area (435 kWh/m2 FA), the lowest specific impact comes from the internal walls (99 kWh/m2 IWA). Note that these values cannot be compared each other as they have a different reference quantity.
3
Application of the cumulative energy indicators
3.1 Estimating the environmental impact of a building To estimate the environmental impact of a building at an early design stage first a reference building or a reference macro element has to be chosen from the reference building catalogue. In the reference building catalogue cumulative energy indicators for two building levels are listed: one on the overall building level and five on the macro element level. The choice of a suitable reference building bases on different aspects such as the function of a building (e.g. apartment house, warehouse, office building), the construction type (e.g. steelwork, brickwork, timber frame), the specific materials for building components (e.g. wooden or aluminium window frames) or the realisation standard of the building (average, high). In the second step, the dimensions of the planned building or macro elements are taken from the sketch. The environmental impact for the overall building is then calculated as follows: Environmental impactbuilding = Area (Volume)building * Indicatorbuilding
(1)
or in the case of calculating a macro element: Environmental impactmacro element = Areamacro element * Indicatormacro element
(2)
The lower the resulting value, the lower is the environmental impact for the building under study. Note that a building which has a low cumulative energy indicator not necessarily has a low environmental impact. If the building has a large gross floor area it can even be worse than a comparable building with a higher cumulative energy indicator. 3.2 Calculating a theoretical case study To illustrate the application of the cumulative energy indicators a theoretical case study is calculated. We assume that an architect plans to build a three family row house. Figure 3 shows a sketch of a model which is under discussion. The building is built in timber frame and the planned gross floor area amounts to 645 m2. For doing an early estimation on the ecological performance of the planned building the architect chooses a reference building from the reference building catalogue (see Figure 3 right hand side). WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Figure 3:
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Sketch of a possible model for a three familiy row house in timber frame (left hand side) and a possible reference building from the reference building catalogue (right hand side).
The ecological indicator for the reference building is 769 kWh/m2 GFA. Thus, the environmental impact for the planned house results in 496000 kWh cumulative energy demand. This value can now be used to benchmark, e.g., to compare the chosen model with instructions or reference values from the tender documents. The value can also be compared with values resulting from an evaluation of the energy consumption from the operating phase of the building. As the architect is still at a very early stage of the planning process he or she can easily adapt the sketch if necessary. 3.3 Adapting the cumulative energy indicators to personal needs The ecological indicators can also be adapted to personal needs. The user might for example want to use another environmental impact assessment method instead of the cumulative energy demand. This is possible by linking the material masses of the reference buildings to another assessment method as described in section 2.1. There exists a variety of databases which allow a direct linking of building materials with their environmental impacts, such as e.g. GEMIS in Germany [16] or Ecoinvent in Switzerland [17]. The environmental impacts of materials and energies can show great variations depending on their production location (example: aluminium production with hydro power versus production with fossil fuels). Therefore, it is important to consider the geographical region where the building under study is located and use a database which covers the region. Another aspect which the architect might want to integrate into his or her calculation is the different life span of the building components. When the whole life cycle of a building is looked at one has to take into account that there usually is a replacement of different building components. For example windows and window frames are normally replaced several times during the life span of a building. To integrate the environmental impacts caused by the replacement of building components new material masses can be calculated by considering the life span. The new material mass (also called life time mass [1]) is calculated by multiplying the mass with the factor lifetimebuilding/lifetimematerial. The cumulative energy indicators are then re-calculated considering the new mass. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
234 Eco-Architecture: Harmonisation between Architecture and Nature 3.4 Quality of the results For the interpretation of the results obtained by using cumulative energy indicators an uncertainty discussion is recommended. Such an uncertainty discussion, which can be qualitative or quantitative, should be done by identifying and weighing all uncertain information encountered during the calculation and application of the indicators. Only by carrying out such a discussion the user can draw sound conclusions on the results. Uncertainties which arise during the calculation of the cumulative energy indicators should be estimated by experts. Such an uncertainty analysis should comprise aspects on both model uncertainty and data uncertainty [18]. Till now, we have made an identification of uncertainties in the different steps conducted for calculating cumulative energy indicators. The results are shown in Table 1. A first estimation on the grade of the uncertainty is given and can be used for a qualitative assessment. Table 1:
Source of uncertainty and grade of uncertainty for different steps in the calculation process of the cumulative energy indicators.
Source of uncertainty Determination of materials - Conversion of building process information into material information - Calculation of material mass - Linking of materials with environmental impact assessment method Environmental impact assessment method - System boarders of process chains - Data survey for material production Determination of indicators - Determination of reference quantities
Grade of uncertainty medium low medium medium medium - high low
Three sources of uncertainty have been identified for the determination of materials from the accounting documents. First there can be an uncertainty when assigning the building process information to one material, e.g. a door can consist of both wood and glass. Second, when calculating the material mass there can be a lack of clarity on the dimensions of a component. And third, there might be “non-fittings” between the material used in the building and the material list of the environmental assessment method, e.g. there might not be the same type of concrete. There are further uncertainties which come from the use of an environmental impact assessment method. Those uncertainties, which sometimes can be quite large, include e.g. the data survey for the production of the building material and the system boarders which are chosen for the production process chain. For further information on this subject the reader is referred to literature, e.g., [18]. A lower grade of uncertainty comes from the determination of the reference quantities from the planning documents. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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For a quantitative uncertainty analysis the grade of uncertainty must be quantified. This would then allow calculating an uncertainty range on the cumulative energy indicators by using quantitative assessment methods such as e.g. Monte Carlo simulation. Uncertainties during the application of the cumulative energy indicators arise especially from the choice of a suitable reference building. This drawback can be overcome by using different similar reference buildings in the sense of a sensitivity analysis. A clear improvement will be reached when the selection of buildings is extended by enlarging the catalogue of reference buildings.
4 Discussion and outlook We have shown that an estimation of environmental impacts of buildings is possible already at an early design phase. The presented cumulative energy indicators can be used for a quick estimation at a planning stage where there is only rough information on the dimension of the building and the used materials. The result can then be compared with other buildings or with a reference value laid down by the client. If the result does not satisfy the needs, the sketch can be adapted or different materials can be chosen. Such changes can be done easily because the information on the environmental impact is available at a very early design stage. The indicators presented in this paper refer to the building construction only. Service installations are not included in our survey. However, as service installations usually have a significant contribution to the environmental impact of a building they should be looked at separately. Today, the database on reference buildings comprises 20 buildings. This is a beginning but to get a use of the cumulative energy indicators as wide spread as the use of economic indicators the reference building catalogue has to be enlarged. This will be one of our main efforts. For this purpose we have access to the building database from the Baukosteninformationszentrum Deutscher Architektenkammern containing the accounting information of more than 1000 buildings. Nevertheless, although the principle of calculating the indicators follows a simple procedure, the work is time consuming. An electronic evaluation of the database will therefore be evaluated. Another focus of our future work will be put on the uncertainty analysis. For a sound application of the developed indicators statements on the quality of the results are imperative. The aim is to provide cumulative energy indicators with an uncertainty range. Therefore, the next step will be to continue the uncertainty analysis by quantifying the grades of uncertainties which until now have been described qualitatively. Then the indicators are re-calculated integrating the ranges of uncertainty for every uncertainty source.
References [1]
Lalive d’Epinay, A., Die Umweltverträglichkeit als eine Determinante des architektonischen Entwurfs, Doctoral Thesis No. 13610 at the Swiss Federal Institute of Technology, Zürich, 2000. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
236 Eco-Architecture: Harmonisation between Architecture and Nature [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14]
[15] [16] [17] [18]
OGIP, Optimierung der Gesamtanforderungen (Kosten/Energie/Umwelt) – ein Instrument für die integrale Planung, http://www.ogip.ch. Vitruvius, Vitruvius – Das Kostenplanungs-, Bewertungs- und Immobilienanalysesystem. http://www.vitruvius.ch. SIA D 0123, Hochbaukonstruktionen nach ökologischen Gesichtspunkten, Schweizer Ingenieur- und Architekten-Verein: Zürich, 1995. SNARC, Systematik zu Beurteilung der Nachhaltigkeit von Architekturprojekten für den Bereich Umwelt, sia-Dokumentation D 0200, Schweizer Ingenieur- und Architekten-Verein: Zürich, 2004. BKI Baukosteninformationszentrum Deutscher Architektenkammern, BKI Objekte – Kosten abgerechneter Bauwerke, BKI: Stuttgart, 1998. CRB Schweizerische Zentralstelle für Baurationalisierung, Baukostenkennwerte-Katalog BKK, CRB: Zürich, 1995. DIN-Norm, DIN 276 Kosten im Hochbau, DIN Deutsches Institut für Normung e.V. 1993. CRB Schweizerische Zentralstelle für Baurationalisierung, Kostenplanung mit der Elementmethode – Hochbau, CRB: Zürich, 1995. DIN-Norm, DIN 277-3 Grundflächen und Rauminhalte von Bauwerken im Hochbau, Teil 3: Mengen und Bezugseinheiten, DIN Deutsches Institut für Normung e.V. 1998. Goedkoop, M. & Spriensma, R., The Eco-Indicator 99 – A damage oriented method for life cycle assessment: Methodology report, Pré Consultants bv: Amersfoort, 1999. IPCC Intergovernmental Panel on climate change, http://www.ipcc.ch. VDI Verein Deutscher Ingenieure, Kumulierter Energieaufwand – Begriffe, Definitionen, Berechnungsmethoden, VDI, 1997. Kasser, U. & Pöll, M., Graue Energie von Baustoffen – Daten zu Baustoffen, Bauchemikalien, Verarbeitungs- und Transportprozessen mit Erläuterungen und Empfehlungen für die Baupraxis, 2nd edition. Econum: St. Gallen, 1998. Kytzia, S., Seyler, C., Stoy, C., Lützelschwab, I., Primary energy indicators for the environmental assessment of buildings. In preparation. GEMIS, Globales Emissions-Modell integrierter Systeme. Öko-Institut e.V., http://www.oeko.de/service/gemis/de/index.htm. Ecoinvent, ecoinvent 2000, Swiss Centre for Life Cycle Inventories, http://ecoinvent.ch. Huijbregts, M.A.J., Application of Uncertainty and Variability in LCA – A General Framework for the Analysis of Uncertainty and Variability in Life Cycle Assessment. International journal of Life Cycle Assessment, 3(1), pp.36-42, 1998.
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Sustainable building design in Australia C. McCabe Cundall, Melbourne, Australia
Abstract The building and construction industry in Australia has taken significant steps forward in the last 3–5 years to improve their environmental performance. This improvement has been in response to increased focus of local/state government policies regarding Ecological Sustainable Development (ESD), as well as the availability of holistic environmental rating tools such as the Green Building Council of Australia’s Green Star rating tools. However the unique climatic conditions of Australia, which range from hot arid to cool temperate combined with its expansiveness generate considerable challenges to building designers in achieving environmentally responsive and sustainable buildings. In addition, designers are increasingly being engaged to contractually meet minimum environmental performance requirements that extend beyond energy conservation/greenhouse performance to cover issues such as water conservation, environmentally credible material selection, indoor environmental quality, transport, ecology and pollution as well as on-going environmental management of facilities. This paper will provide an overview through the combined use of case studies of how designers in Australia are innovatively tackling the demand and contractual requirement for environmentally responsive buildings. Keywords: climate, environmentally responsive buildings, ESD, Australia, environmental design.
1
Introduction
The adoption and integration of sound ESD design principles within the Australian construction industry has taken considerable steps forward in the last three to five years. The historic lip service approach to ESD is being steadily
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238 Eco-Architecture: Harmonisation between Architecture and Nature overtaken by an emphasis on accountability of a building’s environmental performance. This change in attitude has come from a number of directions including the combined drive from local and state government to embrace ESD, as well as the advent of a number of environmental assessment methods which are gaining acceptable within the construction industry. To provide context to the case studies and examples outlined, a brief overview is provided into the design considerations of climate, rating systems and regulatory requirements that building designers are being challenged with to achieve successful environmentally responsive building design outcomes.
2
Understanding the climate of Australia
Climatic conditions in Australia vary considerably and offer significantly different opportunities and constraints in respect to the design of environmentally responsive buildings. Each state offers quite different climatic conditions and seasonal variations that the building designer must respond in order to ensure year round environmental responsiveness and comfort. To assist designers, and in particular allow for energy benchmarking of different building classifications (residential; aged care; office or laboratory or clinic; shop or shopping centre; theatre or cinema; and school), the Building Code of Australia (BCA), the governing national regulatory body, has broken Australia down into eight different climate zones. The eight climate zones range from Zone 1, which reflects a high humidity summer and warm winter, through to Zone 8, alpine. The basis of these zones is shown in table 1 [1]: Table 1: Climate Zones
Table 1: Basis for BCA energy efficiency climate zones.
Description
Average 3 pm January water vapour pressure
Average January maximum temperature
1
High humidity summer, warm winter
≥ 2.1kPa
≥ 30oC
-
-
2
Warm humid summer, mild winter
≥ 2.1kPa
< 30oC
-
-
3
Hot dry summer, warm winter
< 2.1kPa
≥ 30oC
≥ 14oC
-
o
Average July mean temperature
Average annual Heating degree days
4
Hot dry summer, cool winter
< 2.1kPa
≥ 30 C
< 14oC
-
5
Warm temperate
< 2.1kPa
< 30oC
-
< 1,000
6
Mild temperate
< 2.1kPa
< 30oC
-
1,000 to 1,999
7
Cool temperate
< 2.1kPa
< 30oC
-
2,000 to Alpine
8
BCA Alpine areas
The extent of each climate zone is visually depicted in the figure 1 [1]. While these do assist building designers to understand the prevailing climate of particular locations, the boundary lines between the climate zones has had to be simplified by aligning boundaries between zones with local government areas to ease administration. This simplification however does lead to some discrepancies with certain locations being linked to an unrepresentative climate zone for its prevailing climate. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Figure 1:
239
Climate zones for thermal design.
Therefore, while the BCA climate zones provides a rough guide to a locations prevailing climate, building designers require a more detailed understanding to enable full advantage of a locations prevailing climate to be captured in a buildings design response. However, to do so more representative climate must be found. Unfortunately there are limited locations in Australia where hourly weather data (i.e. Test Reference Year (TRY) weather data) for use in performance assessment (i.e. computer simulation) of active and passive solar energy systems, annual energy consumption and indoor climate calculations. For example the two most populous states of Victoria and New South Wales covers 1,028,058 km2 have only 17 sites, most of which are in the city of Melbourne and Sydney. Less populous states and territories have even less, with the Northern Territory having only 3 sites to cover 1,349,129 km2. In consideration of this designers must determine the most representative TRY weather site for locations outside of these limited locations having full 24 hour weather data. One approach is to compare the climates averages (i.e. temperature, humidity, rainfall, sunshine hours, wind speed and direction) of possible representative TRY weather sites with the desired location without full hourly weather data [3].
WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
240 Eco-Architecture: Harmonisation between Architecture and Nature An example of one such comparison to determine the most representative or best fit site with full 24 hour data for a regional site of Ellinbank which has only 9am and 3pm weather data available, is shown in figure 2.
Air Temperature (Deg C Dry Bulb)
30
25
20
15
10
5
0 JAN
FEB
MAR
APR
MAY
JUN
'Ellinbank'
Figure 2:
JUL
AUG
SEP
OCT
NOV
DEC
'East Sale'
Mean daily maximum comparison between Alice Springs (Climate Zone 3), Mount Isa (Climate Zone 3) and Charleville (Climate Zone 4).
Another important consideration is to obtain local knowledge as it can be both useful and sometimes essential. For example Melbourne although considered to have a ‘Mild Temperate’ prevailing climate typically experiences two weeks in summer where air temperatures are the high 30’s and it is not uncommon for it to reach 42 – 44oC. Using the same means of comparison but re-ordering summer and winter months to that of the northern hemisphere, it was interesting to note that the climate of Seville [4] Spain is similar to that of Cashmere Downs - Western Australia and the climate of Coruna [4] Spain is similar to that of Warrnambool Victoria. Thus suggesting that similar building design strategies used to maximise environmental performance could be applied in either location.
3
Regulatory requirements
3.1 Building Code of Australia (BCA) The BCA [5] is a uniform set of technical provisions for the design and construction of buildings and other structures throughout Australia, which allows for variations in climate and geological or geographic conditions. The goals of the BCA are to enable the achievement and maintenance of acceptable standards of structural sufficiency, safety (including safety from fire), health and amenity for the benefit of the community now and in the future. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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The code goes through regular review introducing amendments and improvements following agreement between the Australian Government and each State and Territory Government. One such amendment is the introduction of minimum energy efficiency requirements and targets for residential development including with the aim of reducing greenhouse gas emissions by efficiently using energy, which comes into effect May 2005. Similar energy efficiency requirements and energy performance targets are scheduled to come into effect May 2006 for the other Class of Building (aged care facilities, offices, laboratories, clinics, shops or shopping centres café or restaurants, theatres or cinemas and schools). 3.2 Melbourne Docklands ESD Guide As part of the Melbourne Docklands commitment to and recognition of its role in the development of it has developed an Ecological Sustainable Development (ESD) Guide [6] which sets a minimum ESD performance for development approval while encouraging endeavour towards world’s best practice. The purpose of the ESD guide is to inform all stakeholders about the principles and practices that currently guide the approach to ESD in Melbourne Docklands, as well as outline current environmental policies, plans and systems and explain the performance indicators that will be used to assess the relative ESD design performance for each building in the Docklands. The performance indicators attribute points in respect to different areas based on the developments ESD design response. The ESD design elements covering Outdoor Space, the Site; Atmosphere; Water Cycle and Wastewater; Transport; Energy; Building Materials; Indoor Environmental Quality; Waste; and Innovation. Depending on the developments score, a performance level is achieved from ESD Certificate of Achievement, ESD Award of Merit or a ESD Award of Excellence. The guide covers both residential and commercial development within the docklands and the performance rating of each building is primarily by self assessment with submission to the Docklands Authority for approval. The ESD design response is independently reviewed at each design against the Docklands ESD Guide Performance Indicators. The process is proving to be a success as it is rigorously enforced with all designs being audited at each design stage, resulting in both improved awareness within the development community and design professionals as well as credible and tangible ESD outcomes.
4
Industry and national rating systems
Over recent years there has been considerable expansion in the number of energy, greenhouse and environmental assessment tools being applied within the marketplace. Some are used to achieve market recognition others are used by government and planning authorities to stipulate minimum energy and environmental performance requirements.
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242 Eco-Architecture: Harmonisation between Architecture and Nature 4.1 National House Energy Rating Software (NatHERS) The NatHERS [7] software was developed by CSIRO on behalf of the Australian and New Zealand governments to provide a simulation tool for assessing the energy requirement in houses and apartments. The NatHERS ratings being used to both assist designers to improve a dwellings energy performance and provide a mechanism to set minimum energy performance requirements. The software assesses the energy requirement (MJ/m2/a) of a dwelling based on the passive solar / thermal design of the building fabric and orientation. The resulting performance is then rated from zero to five stars. The software has led to the evolution of accredited state specific assessment tools such as FirstRate in Victoria and is currently going through an evolution phase with a new national software called AccuRate expected later this year. 4.2 Green Building Council of Australia’s Green Star rating systems The Green Star [8] rating systems are a voluntary environmental rating system that provides an appraisal of a building overall environmental performance. The building is assessed under the categories of Management, Energy Use, Health and Well-being, Pollution, Transport, Land Use, Ecology, Materials and Water, to calculate its overall weighted score, which then determines its respective star or performance rating. Current rating tools evaluate new, refurbished and existing office designs with further rating tools under development for other building types such as residential, retail, assembly spaces and industrial buildings. The Green Building Council’s objective is to promote sustainable development and the transition of the property industry to implementing green building programs, technologies, design practice and operations. Although only in its second year the Star Rating systems are being embraced by industry and are being used to provide market differential to developers and building owners. 4.3 Australian Building Greenhouse Rating (ABGR) scheme The Australian Building Greenhouse Rating (ABGR) scheme [9] provides an accredited means of benchmarking an office buildings greenhouse performance. It is a voluntary program for office buildings, designed to enable Base Building (central services), a Tenancy or for the Whole Building performance to be assessed. Providing building owners, managers and tenants to get market recognition for superior greenhouse performance and identify ways in which greenhouse performance can be improved. Ratings can be carried out for existing office buildings based on actual metered energy consumption and new buildings based on energy consumption determined using their validation protocol for computer simulations. The respective greenhouse performance of an office is rated from one to five stars in incremental and ½ star steps. With a 1-Star reflecting a building with poor energy management or outdated systems, though to a 5-Star which represents a
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building that is as good as it gets, due to its integrated design, operation, management and fuel choice.
5
Case studies and examples
The following provides a brief introduction and overview of a selection of case studies which provides insight into sustainable buildings are being delivered in Australia, which will be expanded and elaborated on in the formal presentation. 5.1 30 The Bond, Bovis Lend Lease headquarters Recently completed headquarters for Bovis Lend Lease, which took a strong and integrated environmentally focused approach to its design. The building comprises approximately 18,700 m2 of office space, a 600 m2 communal atrium and basement parking for 113 cars. Selected Sustainable Design Features • Australia’s first predicted 5-star ABGR greenhouse performance rated office building. • 5-Star Green Star pilot rated design. • First large scale use of active chilled beams in an office development. • Operable external shading on western façade that deploys progressively during the day to maximise views and minimise solar heat penetration. • Maximised useful penetration of daylight into the building via the perimeter and atrium. • Distributed naturally ventilated sunrooms on each floor taking advantage of Sydney’s climate. Figure 3:
30 The Bond, Bovis Lend Lease headquarters.
5.2 Modernisation of DNRE Regional Institutes Modernisation of the Department of Natural Resources and Environment Dairy Research Institute at Ellinbank, Regional Offices at Horsham and Regional Tatura Offices. The integration of environmentally responsive design principles was a key requirement and client objective for each project and led to highly innovative design solutions. Independent review of the environmental design solutions, were also a key client driven requirement of the project. 5.3 Monash Science Centre The new Monash Science Centre will serve as common ground to bring research scientists and primary / secondary students as well as the general public together, WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
244 Eco-Architecture: Harmonisation between Architecture and Nature encouraging their interaction and promoting an exchange of ideas and information. Sited on a green field site, the building comprises of two main pods: a classroom wing and exhibition hall. Selected Sustainable Design Features • Non-refrigerative air conditioning through the combination of a thermal labyrinth and creek water storage system in Ellinbank. • Thermal labyrinth to pre-condition incoming outside air for Link Building at Horsham. • Particularly strong emphasis on water conservation, rainwater harvesting for re-use and process water collection, treatment and re-use. • Integration of free daylighting, ventilation, night-purge strategies.
Figure 4:
natural
Modernisation of DNRE Regional Institutes. Sustainable Design Features • Hydronic underfloor heating is used throughout, below the timber floor for winter comfort control. • Heating requirements provided by a geothermal field within an adjacent permanent retard basin. • Summertime comfort control in the exhibition hall is achieved through combined cross flow ventilation / stack ventilation and both single and cross ventilation in the classrooms. • Diffuse daylight throughout classrooms via carefully configured glazing and light shelves. • Environmentally credible material selections. Figure 5:
6
Monash Science Centre.
Conclusions
Australia has taken considerable steps forward from an ESD perspective, achieved through the combined push for the introduction of regulatory requirements and targets, as well as the recent presence of independent greenhouse and environmental rating tools. Increasingly ESD is becoming an inherent consideration in the design of buildings. The construction industry is WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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being challenged to take an integrated design approach and to date is striving to meet this challenge. Although the climatic conditions in Australia vary considerably from State to State requiring different design approaches and solutions, there is considerable potential within Australia to take advantage of its climate to achieve strong environmentally responsive outcome. However, considering the strong similarities between the climate of Australia and Spain, it would have been interesting from a building design perspective if it had been colonised by a more Southern European country such as Spain.
References [1] [2] [3] [4] [5] [6] [7] [8] [9]
Energy Efficiency BCA 2005 Volume One – Regulation Document, Proposal for Class 5-9 Buildings, RD 2004-01, November 2004, p 5. BCA 2005 Volume One – Class 2 to Class 9 Buildings, pp 22 - 24. Australian Government, Bureau of Meteorology, website, www.bom.gov.au. Spanish Weather Data, website, www.bbc.co.uk/weather/world/ city_guides. Building Code of Australia (BCA) 2005 Volume One and Volume Two Melbourne Docklands, ESD Guide, downloadable from www.docklands.com/docklands/about/publications/esd/index.shtml. National House Energy Rating Scheme (NatHERS), www.energysmart. com.au/les/Displaypage.asp?flash=-1&t=2005453&PageID=309. Green Building Council of Australia (GBCA), Green Star rating systems downloadable from www.gbcaus.org/greenstar. Australian Building Greenhouse Rating (ABGR) Scheme, website www.abgr.com.au.
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Design and construction: changing the role P. Rossi DiPSA: Department for Project and Study of Architecture, Roma Tre University, Italy
Abstract Since the seventies many experiences have gone towards alternative or soft technologies, architecture for the poor, etc. In all of these the design was in answer to a need. Is it possible to consider building as an opportunity? Certainly, when the architecture is used, some functions or needs can be satisfied. But the building process itself represents a way to knowledge, a research field, a social event, a door opened on the future (while the need is a result of the past). Within this area we could try to involve groups of non-experts in the design and construction process, which allows one to have a direct interface between individual needs and production. Specifically, during two workshops in secondary schools in central and southern Italy, the pupils have built from recycled material a theater stage in the first case and the stands for a little market in the second one. Some university students have guided the secondary students in the construction process using newspapers, cardboards, tetrapak and cables. A third project, larger than the others, consists of a modular shell, made by a folded wire mesh, covered with cement, sand, paper or fabric to self-build (thanks to the direct help of the university students) a family house for sick children in Kenya. Decomposing design and building process in single phases is in accordance with the segmentation of industrial and economical processes of our contemporary world. Generally, nowadays architects are frustrated about this situation where they can’t be the only “art director” anymore. On the other hand, if well managed, this segmentation can be the opportunity to receive at each step all those virtuous inputs, which can arrive from a widespread knowledge even if not structured and specialized in any way or from disposable resources like recycled materials, free work, etc. Keywords: lightness, environment, shell, low cost, self-construction, innovation, technological transfer.
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248 Eco-Architecture: Harmonisation between Architecture and Nature
1
Introduction
I don’t believe that the pattern of advanced countries can be the same to help the poor regions in their development processes. Specifically in the last period the basic technologies of the so-called western countries (or better, productive system) have been producing a growing distance between rich and poor nations in the world. The way of forced industrialization means pollution, exploitation/exhaustion of human and natural resources, social costs. The current performances of China are exemplary. Even if the richness of the nation is growing up in a spectacular way, the quality of the air in the cities is a danger for the health of people, there aren’t any laws or measures to protect the environment, nor to guarantee old and young workers. The damage will be paid by the next generations in a more than proportional price. The enormous slums around the cities in Africa, Southern America or Asia are another dramatic manifestation of the uncontrolled contamination between different social and economic systems. Burning metal sheets are used as roofs under the African sun, dusty lands are full of houses without infrastructures, quotidian needs thwart every poly-annual project. As Amartya Sen has demonstrated, the best results can be obtained by operating directly towards the culture of common people instead of waiting for the development of productive structure [1, 2]. And the culture is not only theoretical or humanistic. I work in the field of material culture and in this field I look for a satisfactory result. There are the evaluation criteria that change or should have to change in a project, not only humanitarian, but also environmentally and socially sustainable. While the advanced productive system needs a strengthening of infrastructures to regain competitiveness, in the backward situations more useful are the proposals with a low level of investments and capital. It’s not a question between bamboo can and carbon fibre, but understand that hanger and famine have to be fought with different weapons from those of commercial competition [3].
2 Working method What is the difference between learning by doing and knowing by doing? While learning is referred to something already known, which has to be reproduced, knowing signs a direction, an aim towards which to proceed. So doing assumes the role of the experimentation aimed to improve life and environmental quality. To be coherent with this assumption, the objective of the design process can’t be established at the beginning, but it can be discovered step by step, during the experimentation. Before starting there are ties and opportunities that depend on the disposable resources in terms of involved people, geographical context and financial supports. The ties assumed as the foundation of our experiments concern of: Suitable technologies, referred to the buildings performances, the employed technologies and the use of natural resources [4, 5, 6, 7, 8]; WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Light structures, referred to the employed materials (which should be possibly renewable or recyclable), the structural morphologies and the industrial, manual and conceptual processes they imply [9, 10, 11, 12]; Temporary architectures, referred to the function and the historical presence of the buildings, which can exist during the lifetime of one or two generations or just for the duration of a specific event. These three criteria help us, and our specific working teams, to guide the design towards a low environmental impact, a better social integration, and an improvement of the natural and anthropic environment.
3
Young builders
The way of experimentation started some years ago at the Environmental Design Course (Faculty of Architecture – Roma Tre University) where students extracted the form, the structure or structural behavior and the use from the matter/material. Obviously structures and materials are light to build envelopes that improve the habitability of the places. Shells and membranes are designed and verified mixing nets, cans, jute, threads or wires, some polymers, leafs, cotton, and others. The difference between the described selection work and a traditional design process consists in the possibility to keep numerous variables for a same problem and crystallize them step by step while the single problems get clearer without never renouncing the starting criteria of suitability, lightness and temporarity which guarantee in nuce environmentally and socially coping responses. At the end of this phase, which can be defined as intersection point between design and research, I have selected the best students’ proposals in terms of practical feasibility, architectural and urban relevance, correspondence with the demand of potential users. It’s mainly at this stage that the frontiers of technological innovation confront themselves with the emerging human needs, like those of the metropolitan disadvantage areas. But in this direction my efforts haven’t produced any result. To promote the culture of sustainability also out of University, my workgroup could try to involve groups of non-experts in the design and the construction process, with a direct interface between individual needs and athropic/physical/economic environment. Symmetrically some secondary schools have got in touch with the workgroup to be helped in their environmental education projects. Recently we have completed a stage for a school in Aprilia, close to Rome, using newspapers and boxes. Now we are engaged with a school at Morano Calabro (south of Italy) in the building of a temporary market. Looking at the experiments or proposals of students in the Environmental Design course, some of the most interesting ones are based on the recycle of paper or cardboard packs. They can design a shell more or less suitable to the various opportunities that can arise to build these temporary architectures by cutting, folding, stitching or gluing the sheets, The implicit building technique is to go back from container to sheet, to shape the sheet according to a geometrical law, to preview the resistant nervures, to WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
250 Eco-Architecture: Harmonisation between Architecture and Nature realise the double sweep surfaces, to complete, if necessary, with some cables in order to stiffen and consolidate the shelter. The commercial milk or juice containers loose immediately their characteristics to assume the new designed identity. This building activity helps to accept the traditional market, organized at the end of scholastic year to sell the objects made by students at Morano Calabro. The paper shells are thought as stands to show and sell the students production. Moreover we are looking for jointing the paper or cardboard sheets with a photovoltaic film to make the shells self-sufficient in terms of energetic supplying for night lighting. The stratified origin of material used in packaging seems to suggest a diversified use of each layer to solve specific needs as the energetic autonomy. Students pick up the containers for food or juice at home, neighbours or shops. Besides the simplicity in manipulating this material, the choice is motivated by the hope to compensate, even if in a small part, the waste produced by consumerism. This satisfies the didactical objectives of the jointed initiative to promote the environmental education. The aimed objectives are: - educate the youths to take care of their environment developing a waste reclamation activity; - revaluate to the manual skills as a tool to transform the prime matter; - relate the knowledge with the doing; - discover the natural and anthropic environments, observing the characteristics and the implications through the construction of a habitable envelope with own form, resistance, stability, lightness. Before building the market envelope, university students have organized two workshops for secondary students, where they examined the geometrical law of the construction and the conditions of structural stability or resistance. Intuitively, if I transform food containers, I’ll obtain a polygonal module to combine in the space. In this way I can realize a double curvature surface, but the polygonal module and the connecting system have to be thought to permit an angle between two close pieces. With the attention not to solve the problem designing a lot of different polygons, because the young constructors can have difficulties to follow too many complex instructions. The CAD software easily permits to obtain a series of plane polygons from every kind of surface, but then I have to number each piece and the relative position on the surface. And this is not enough, because it becomes necessary to cut the pieces with much precision. A slight approximation, repeated many times, can make the building of the market envelope impossible. The solution has been found by cutting the four corners in a particular way. This permits to fold the sides of the sheet to obtain the veins of curved shell and let the range of the polygons variation requested by the curvature. So, the ninety per cent of the construction is made by the same piece, the rest needs special connections, adapted in progress (by university students). A clear design strategy and the right balance between technical experience, figurative control and dilettantish spontaneity can concur to build sustainable and aesthetical architectonical results. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Low cost technologies
Still now I have talked about building experiences that are between the play and the research. But, once engaged in the self-construction field, new ways are open, new aims become reachable. A strong impulse to deepen the researches is derived from the meeting with a NGO, called AINA that works in Kenya to offer better life conditions for children. Now AINA is engaged to realize a family house for about twenty youths, positives at the HIV test. When they come out from the hospital, the local community tends to outcast these youths. So it was born the idea to organize a self-sufficient group in a small structure based on agricultural activities. In the cooperation activities, architecture doesn’t represent the central aim of the project. The humanitarian and economical objectives are the heart and the soul of the activities. Architecture plays a secondary role, as it can be useful to facilitate the objectives. The technology role can be different: introducing a new criterion in the use of a prime matter, promoting conditions for the self-knowing are qualified objectives in the cooperation activities [13, 14, 15]. So, when I’ve chosen poverty and cooperation as the theme of the university design course, students’ work has left the traditional typologies or architectural organism spontaneously. They prefer reasoning directly around surfaces that separate an interior from an exterior to control climatic conditions, improve the habitability of a site. In this kind of approach, the envelope substitutes the functional distribution. The reference isn’t a commercial target, with its consolidated preferences, habitudes, and behaviours. Facing poverty, the solution has to be searched simplifying the problems, accepting a partial satisfaction for more people than a better answer for few people. The most interesting students proposals are based on three kinds of constructive systems. Someone prefers working with the bamboo can that is cheap and diffused in many poor countries. Some others prefer mud following the traditions of the local contexts. But I’ve tried to valorize a third kind of proposals, based on a new mix of materials that seems to be in conformity with two priority aims. At first, working in the field of lightweight structures has a better response to the environment (not only in the poor countries, but even in the rich and developed ones). Secondly, it could be an important opportunity for the local productive structure, compared with a different use of manual or primitive operational tools, to introduce a new vision of technology [16, 17]. In fact, a recurrent objective of the cooperation projects is the technological transfer towards the local enterprises. In this case the transfer isn’t referred to a specific mechanical tool or manufacture that needs high investment, but shows how many different ways can valorize natural and anthropic resources, beginning from the human work that is easily disposable in the poor countries. If the problem is organizing the work of about twenty university students to build a family house at Igoji (Kenya), what can this workgroup make in two or three weeks? What kind of materials are they able to manipulate? How are they integrating with the local productive structure? WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
252 Eco-Architecture: Harmonisation between Architecture and Nature The definitive design of the family house has been based on some precise points: 1. the wire mesh can be easily folded (by cutting and superposing the borders) to obtain a shell with a double curvature. Since the wire mesh is sold in rolls 1 meter high and 25/30 meters long, the envelope has been divided in strips or arcs, jointed together to form a sort of tunnel. This form becomes solid and resistant with a jute fabric soaking with cement; 2. the comfort depends on ventilation more than on isolation. So the discontinuity of the tunnel (changing the dimensions of the section) guarantees the ventilation and there are enough local poor materials, like leaves, barks or straw, mixed with cement and sand, to insulate the envelope; 3. the energetic autonomy can be helped by photovoltaic cells distributed on the surface of the envelope. Some parts of the family house have thought to be constructed by local building contractors. Specifically the groundwork, the internal walls and the hydric and electrical equipments are under the competence of some Kenyote operators. Despite the choices about manual skills and non-expert workers, the architectural manufacture rising in my description has also a perfect feeling with the simulation software. Specifically the shell in wire mesh can be virtually constructed modeling the so-called NURBS (Non-Uniform Rational B-Splines) and jointing the different sections of every metal net strip. In a Loft-NURBS the arc on the border of the strip is smaller than in the centre, so we have a curved section of the strip that covers the arc. Introducing a variation criterion we have obtained a figurative performance of the envelope without modifying any other characteristic (low cost, self-construction, etc.). We have designed a non-circular arc, preferring a spiral section for the tunnel. If the spiral centre changes progressively strip by strip, the architectural volume acquires a dynamic image, following the recent aesthetic researches made by Miralles, Eiseman, Nox (just to remember the most famous ones). Finding a role to calculate the progressive differences of the distance between the folds that generate the double curvature of the shell is enough. The virtual model is also necessary to complete the structural calculus that confirms how the shell form is resistant and stable with a thin thickness. Before leaving for Kenya we have realized a prototype (about 5 x 2 x 3 meters) of the tunnel at the AINA courtyard in Rome. The first tests haven’t got a good result because: the net had a too much large mesh; the discontinuity of the curvature was a critic point during the assembly; the way to consolidate the shell with the cement was wrong, etc. Finally the building system went on. Pulling near the folds the curvature ray of shell decreases. A more convex curvature offers a better resistance. Balancing the curvature of the arc and that of strip (orthogonal at the arc) it can be possible to obtain the desired stability and resistance. Immersing the jute fabric in a liquid mortar, the cement layer is distributed on the wire mesh regularly, without any specialised manufacture or workers. After the hardening, mesh, fabric and cement, become an only integrated material, to shape a rigid shell. Combining two layers with an empty WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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space in the middle, the wall becomes aired in order to offer the best habitability in wet and hot regions.
5
Conclusions
Today the technology innovation collides with the architecture. It’s organized and produced in two operational areas: the productive system that promotes a useful innovation in the increasing competitiveness, productivity, etc.; the scientific institutions that develop research programmes directly or indirectly oriented to consolidate the productive system. The architect role has a different aim, because it’s closer to the coordination/control of operational tools (design methods, equipments, building techniques) more than to the invention of new technical tools. Specifically the self-construction is an argument without interest for industries, craftsmen, research centres, even if, this has a direct relationship with poverty, social outcasting, big geographical regions, most people in the world. The best individual or collective satisfaction generally motivates more or less a radical renovation of the practice. But, because this happens, new tools or solutions are often necessary and, once again, they need inventions or ideas. The invention proceeds in a chaotic way, developing among many sectors and coming from unpredictable circumstances, sites or times. The duty of design is to manage the invention inside collective objectives, related to environment, economy, culture, society, etc. It’s difficult (and often useless) teaching or classifying the innovation, because each piece of information can be at the same time revolutionary or conservative. It depends on the context. For instance, many times the observation of nature has inspired the technical or scientific innovations, but many other times it has been the cause of ostracism towards the new approaches. It will be more useful, maybe, to promote the practice of innovation, choosing to be active subjects in an experimental research process, instead of limiting themselves to be the consignee of solutions invented by others.
References [1] [2] [3] [4] [5] [6] [7] [8]
Amartya Sen, Development as Freedom, Anchor, 2000. Amartya Sen, Commodities and Capabilities, Oxford University Press, 1999. Jeremy Rifkin, The European Dream: How Europe's Vision of the Future Is Quietly Eclipsing the American Dream, Jeremy P. Tarcher, 2004. Bernard Rudofsky, Architecture Without Architects: A Short Introduction to Non-Pedigreed Architecture, University of New Mexico Press, 1987. Paul Oliver, Dwellings, Phaidon Press, 2003. E. Komatsu, A. Steen & B. Steen, Built by Hand: Vernacular Buildings Around the World, Gibbs Smith Publishers, 2004. Bob Easton & Lloyd Kahn, Shelter, Shelter Publications; 2000. Lloyd Kahn, Home Work: Handbuilt Shelter, Shelter Publications, 2004. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
254 Eco-Architecture: Harmonisation between Architecture and Nature [9] [10] [11] [12] [13] [14] [15] [16] [17]
E. Kullmann, W. Nachtigall, J. Shurig & other, IL 8: Nets in Nature and Technics, Institute of Lightweight Structures (IL), University of Stuttgart, 1975. K. Dunkelberg & The Team of IL, IL 31: Bamboo, Institute of Lightweight Structures (IL), University of Stuttgart, 1985. J. Schlaich & R. Bergermann, Light Structures, Prestel Books on Architecture, München 2003. M. McQuaid, Shigeru Ban, Phaidon Press Limited, London 2003. United Nations Human Settlements Programme The Challenge of Slums: Global Report on Human Settlements London and Sterling, VA: Earthscan Publications, 2003. K. Tranberg Hansen & M. Vaa, Reconsidering Informality: Perspectives from Urban Africa, Nordiska Afrikainstitutet, 2004. I. Imparato & J. Ruster Slum Upgrading and Participation: Lessons from Latin America (Directions in Development), World Bank Publications, 2003. Stanley Abercrombie, Ferrocement: Building with cement, sand, and wire mesh, Schocken Books, 1977. David Pearson, The New Natural House Book: Creating a Healthy, Harmonious, and Ecologically Sound Home, Fireside; 1998.
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Section 4 Assessment and selection of materials
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Natural materiality – the people’s choice F. Stevenson School of Architecture, University of Dundee, Scotland
Abstract Despite the variety of toolkits, life cycle analysis, models, and other forms of guidance on sustainable resource use in architecture, the amount of energy used and waste created in the industry is going up on a global basis. The conventional approach to promoting sustainable specification clearly isn’t working. This paper offers a new approach based on a recent qualitative case study of people’s attitudes, associations and understanding of key construction materials in housing. The findings suggest that people have a deep tacit knowledge of materiality which draws on the ecological “affordances” offered by materials and are very clear about which materials they want, where, and why. These affordances, identified in Gibson’s theory of ecological perception, transcend the usual subject/object divide and challenge designers to do likewise. This tacit knowledge appears uniquely related to people’s place of upbringing as well as their occupation. It supports the notion that a bioregional approach should be adopted for material and product specification which empowers users to take more responsibility for the materiality of the buildings they live and work in. The emotional “endearment” of materiality in architecture to the users is argued as a key factor in potentially reducing maintenance costs and subsequent resource impacts. Currently, architecture is conceived primarily as the design of space using construction resources. Reframing architecture as the design of resource use in place, draws on users’ local knowledge and an implaced, more natural materiality. Design and research are thus challenged to focus on a more limited palette of materials, based on the findings of the study, and work to the edge of technology in developing building elements related to these. This way of working can then be closely linked into the eco-systemic processes which underlie any sustainable design endeavour that aims to harmonise with nature. Keywords: materiality, sustainable resource use, construction materials, ecology, tacit knowledge, place, architecture. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060261
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Introduction
“Which material should I use for this element of my building?” It’s a common enough question that all architects ask themselves at some point in the design process. The answer depends on how much awareness and understanding there is of the various design parameters involved and the skill and knowledge available to select and integrate the chosen material within a coherent design proposition. A quick list of these parameters would include: functionality, aesthetics, symbolic value, availability and cost. Due to the current economic de-coupling of resource reserves from true environmental cost, a later addition to this list is the self-conscious concept of sustainability, with its triple bottom line of environmental, economic and social concerns. Whatever our definition of sustainability is, it is often framed as a question of freedom .v. limits. Traditionally, buildings and the use of construction materials evolved slowly over time with subtle innovation that responded to needs and limits. Contemporary design is synonymous with relatively limitless innovation, often for its own sake, largely because capitalist economies need to both meet and create needs. Architects are wary of sustainability with its imperatives and apparent limitations, seeing this, still, only as a necessary appendage to their design process rather than an integrated part of it (Ryhaug [1]). Architecture as a discipline is therefore not leading the way on the reality of sustainable specification but has largely retreated into the spectacle of visual and spatial innovation with materials. The evidence for the need to design more prudently with our existing physical resources has never been more compelling. Demand for oil is predicted to outstrip supply as early as 2008 according to some estimates. The loss of these supplies will potentially remove many oil-based construction materials in a relatively short space of time. It is also estimated that we will need to reduce physical resource use through efficiency gains by a factor of twenty if the construction lifecycle is to remain sustainable (Kasteren et al. [2]). Despite this, mainstream research to date has largely failed to adequately address the need for appropriate evaluation of sustainable construction, often producing inaccurate generic “tick-box” type information on sustainable specification (Stevenson et al. [3]). The use of a more people and place-centred approach is explored in this paper. This is a new approach to sustainable specification which may yet engage the designer and user alike.
2
Approaches to sustainable resource use
Despite the huge variety of cultural responses towards materials, construction science has developed a remarkably homogeneous and global approach towards sustainability (Guy and Shove [4]). The leading players in the field of generic specification are the USA and Europe, using mechanisms such as the ISO standards worldwide, and the Eurocodes in Europe which promote energyintensive construction materials and products, whose added economic value is WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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ironically reflected in the number of transport miles they can clock up. They are supported by the deductive reasoning of Life Cycle Analysis, and Eco-labelling, whose testing regimes can marginalise local and relatively unprocessed materials (Morton and Little [5]). By contrast, traditional cultural approaches to material specification are predicated on a sense of living with the earth, drawing on sustainable living traditions and practices which provide a vehicle for passing on local knowledge through deeply held beliefs and the teaching of skills (Ingold [6]). A number of ecological architects have picked up on this knowledge through working with relatively natural materials in their own locality. Biodiversity, environmenteconomy integration and participation are automatic considerations in this holistic approach to sustainable specification. The question is; which of these approaches is delivering on key sustainable construction targets? Energy costs and material consumption in construction are still rising on a per capita basis, despite efforts to reduce these (Kibert et al. [7]). In fact, generic specification makes it harder to re-use materials and privileges energy-intensive recycling processes. Although various scientific tools and checklists for sustainable construction are produced worldwide, their impact on the industrial world is negligible and for the rest of the world non-existent (Kohler [8]). This suggests researchers should be looking at other ways of evaluating sustainable construction materials which are more inclusive.
3
The architectural discourse on materiality
One way of re-evaluating the sustainable specification of construction materials is to expand the parameters of consideration. Whereas construction science is strictly concerned with the physical properties of matter, materiality in its widest sense is the understanding of how meaning is attached to matter through our experience of it. There are few texts which deal specifically with the cultural interpretation of construction materials as they are used in buildings, and virtually none that examine sustainable materiality. One reason for this might be because the tacit nature of materiality is built on the repetition of successful design efforts and becomes a matter of habit (Leatherbarrow [9]). Examples include the unquestioned use of standard details and materials despite the excessive resource depletion involved, and their thoughtless transfer between differing climates and cultures. Such texts on materiality that do exist, tend to debate the “truth” of materials, but any physical truths are continually subverted in architecture through aesthetics desires which are seen as superior, thus presenting a dichotomy between common sense and visual representation. Within architecture, formal gestures towards sustainable materiality often visually copy the ecological processes involved, without really understanding them, and thus undermine their intrinsic truthfulness. Even avowed environmentalists within architecture can be prone to supporting a misrepresentation: “What is important is the fact of a material’s presence, not its readability. Wood may be painted to look like aluminium, but the deception is harmless” (Hagan [10]). It will be argued here, WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
260 Eco-Architecture: Harmonisation between Architecture and Nature that such architectural misrepresentation of physical truth to materials is not only harmful, but can be a matter of ecological survival in terms of evaluation. The continuing disjunction between how architects and researchers choose to evaluate materials and how these are actually functioning within situated environments undermines ordinary people’s understanding of those environments and their respective eco-systems to the detriment of both.
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Tacit knowledge and affordance: re-evaluating sustainable construction
A key aspect of evaluating materials is people’s perception of them. Ecological psychologists have developed Gibson’s theory of “affordance”, which claims that the value and meaning of things in the environment can be directly apprehended through the body’s interaction with the environment. It is the persisting surfaces of the environment which provide the framework of reality. If a surface is horizontal, it “affords” support and can therefore be stood upon. Equally, a material’s affordances can be perceived in terms of strength, comfort or protection. Stone offers strength through resistance; wool offers comfort through warmth and softness. These affordances are neither purely objective nor subjective –they are both, and cut across the usual subject-object divide in evaluation. They do not change as the need of the observer changes –the affordances are always there, waiting to be perceived, in materials that are not value-free, but value-rich as ecological objects (Gibson [11]). We draw on this wide variety of inherent affordances according to our needs; the “warmth” of wood for the intimacy of a home interior can, for example, be contrasted with its relative “solidity” in a door for protection. An essential part of Gibson’s theory is that things must look like what they actually are to provide appropriate information for perception. Things which don’t look like what they are provide environmental misinformation for the perceiver. This is because people do not simply perceive good form; what is seen are different opportunities to act, such walking, sitting, resting, climbing, moving, or using, according to Vihma [12]. When this is applied to the evaluation of construction materials, it is clear that they should express affordances unambiguously in order to ensure a good match between users’ needs and their understanding of their construction environment. While ecological psychology argues that the inherent meaning and value of materials are discovered or detected, constructivists suggest that individuals also impose value judgements on materials based on their personal beliefs, which are tested over time for validity. Critical theorists add to this brew, by pointing out that these value judgements are then socially prescribed by society which legitimates certain judgements and not others. Thus, even where certain materials may provide greater affordance for satisfying our needs, the construction industry will continue to be able legitimise unsustainable substitutes as more “normal” given the social requirements of capitalist reproduction. An example is the substitution of natural wooden panelling with laminated wooden panelling which pretends to be wooden but this is only as deep as the photographed image WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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of the wood on its surface. The glued laminate is also difficult to re-use, recycle and is non-biodegradable. This is now legitimised as normal “wood” type flooring. It would seem then, that while materials offer certain natural meanings and values, we also select what meanings and values to ascribe to them as a result of our learning experiences and internalised normative processes. Some of these influences are more tacit and others more explicit. Tacit knowledge of construction materials is a personal appraisal based on an inarticulate set of pre-suppositions that have been assimilated subconsciously over a lifetime from various sources, including bodily experience, cultural normalisation and social experience, according to need. These form an immense and subtle understanding which we innately know how to draw on, comply with, and live by, without specifiably knowing its content (Polanyi [13]). Arguably, any understanding and accreditation of construction materiality, should therefore be coincident with the particular tacit rules shared by the community of any particular place. This notion was explored in a recent qualitative case study by Stevenson [14].
5
The case study: a people-centred approach to sustainable materiality
The study considered two culturally distinct groups of people to see what role place had in their understanding of materiality. The participants consisted of twenty local residents who had grown up in a culturally and physically homogenous region of NE Scotland, and a control group of twenty new residents who had grown up in a range of other countries. They were interviewed in depth using a technique called The Repertory Grid [15] which revealed their various beliefs, or “constructs”, concerning various construction materials. Construing, as opposed to conceptualising, is essentially a dynamic search for personal understanding evolved through recognising similarities and differences in our experiences, which are then stored as assumptions. A combination of Content Analysis and Principle Component Analysis was then used to analyse the results and identify the key themes. Nine common construction materials were examined using deliberate mix of traditional and new as well as reflecting different degrees of processing from raw resources: wood, stone, concrete, steel, glass, clay brick, plastic, gypsum plaster and mud. The key findings of the study were that each group differed significantly in the way that they construed construction materials, suggesting that geographic location plays a key role in determining people’s attitudes to materials. Stone was generally the material of choice for the Scottish group, reflecting its prevalence in their locality, but this was not the case for the control group. Emotional feelings were used as the primary means of evaluation overall, followed by construction function and purpose and whether a material was more or less processed. Interestingly, the Scottish group appeared more concerned with construction function and purpose, including durability, compared to the control group.
WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
262 Eco-Architecture: Harmonisation between Architecture and Nature There were also significant gender differences, with women appearing more concerned than men with the social aspects of materials, including the homeliness, warmth and comfort offered. Additionally, men related more to the qualities of strength in a material, whereas women focussed on its “naturalness” related to the degree of processing and sourcing from relatively natural environments. There was an overwhelming preference in both groups for wood, stone and glass, and a distinct antipathy towards concrete, plaster, mud and plastic. Women, rather than men, related to glass as a “social” material, because of its ability to provide visual connection. Individuals also demonstrated a surprisingly sophisticated approach to evaluating materials using a wide range of criteria and showing significant discrimination. Their occupation also influenced the way in which they appraised materials, with those involved in craft and design occupations, rather than administrative ones, tending to relate to the materials in terms of what they could physically do with them. For both groups, the appraisal of materials was primarily in terms of subsistence, protection, identity and understanding their function. Virtually no mention was made of energy efficiency or waste minimisation which suggests that there is a poor connection between people’s ways of evaluating construction materials and the way that the literature on sustainable construction conventionally evaluates these materials. This does not necessarily mean that people are unaware of these issues, given that they are at the forefront of government publicity campaigns, but that they relate to materials more tacitly and holistically on both a physical and metaphysical level. This finding presents a fundamental challenge: how can the technical discourse on sustainable construction resource use and materials meaningfully re-engage with issues of locality and culture?
6
Materials with a sense of place means materials with meaning
When individuals were asked about how their personal evaluations of construction materials might best be promoted, several clear themes emerged. These suggest a new way forward for the discourse on sustainable construction resource use drawing on the relationship between people, materials and place. Firstly, although 70% of all participants grew up in cities, there was a consistent reference to the more natural environment of the region in which they had lived, and the importance of understanding this in relation to the materials that “belonged” there. Through their childhood upbringing, they had a special bond with the relatively unprocessed materials associated with the more natural environment of the region and a deep understanding of how these should be used in relation to both climate and associated cultural traditions. There was also an understanding that the local knowledge which embeds the use of materials in their place of origin, through a deep understanding of local climate and topology, must be handed on from person to person over time rather than reproduced in abstract books. This tacit knowledge is arguably activated and developed through people’s changing needs over time interacting with natural affordances. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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The desire for a sense of identity and understanding in relation to construction materials was again related to a sense of place, often with clear references to the particular way in which materials were used in a given place through local construction techniques and local crafts. Place therefore provides a profound sense of orientation through repetition, familiarity, experience and attachment and the materials found in place are a part of this. This bioregional approach to materiality, which includes local cultural, social and economic as well as physical and geographic dimensions is seen by Cooper [16] and others as perhaps the most complete way of approaching genuinely sustainable construction. It is a fundamentally empowering process for the users and developers of local buildings, because it creates a virtuous circle of local economic development through the use of local resources in local environments, thus keeping people orientated and in touch with an understandable local identity.
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The emotional design of resource use in place
A second theme relates to the emotional attachment that people in the study expressed towards certain construction materials. Gibson’s theory of affordance suggests that our ability to survive is directly related to our evolutionary perception of what an environment physically offers to us. In terms of construction materials, we appear to relate to them in terms of how they can meet our personal needs, rather than thinking of them in remote or generic industrialised terms. This attachment to materials and their use within a building has consequences for sustainable construction. As Kasteren [17] points out, “A beloved building probably requires less maintenance, because the people who work there (or live in the vicinity) become attached to the building and thus treat it with more respect”. Architects can therefore potentially reduce contracted maintenance costs by drawing on the free care provided by people who will look after, and take pride in, local materials used in the building. This emotional endearment of construction materials is a new factor to take into consideration when trying to evaluate them in terms of their inherent sustainability. It is a relational way of considering construction materials that is unfamiliar territory for building scientists but not for architects. What is new for many architects is the idea of harnessing the emotional meaning of materials to sustainable resource use. It is arguable that sustainable construction is ensured by referring to the users themselves, the needs that they have and the specific and local manner in which they believe these are satisfied. In effect, this means re-framing of architecture as the emotional design of resource use in place rather than the design of space using construction resources, which is how it is predominantly conceived. This consideration of place and user in relation to resource use is now considered in relation to developing work in the fields of ecology and anthropology, which have further consequences for the sustainable specification of construction materials.
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Cultural eco-systems and construction materials
The combination of systems theory and ecology has, over the years, provided a firm platform for the scientific development of sustainable construction resource use which has led to the emerging field of construction ecology. More recent developments in eco-system theory include work by Kay [18] and others on the ability of ecological organisms to develop through emerging properties in a system that attempts to re-establish equilibrium in the face of change. This has been termed SOHO (self organising hierarchical open) systems. Importantly, it suggests that within eco-systems, new knowledge emerges from the bottom up, rather than being imposed from the top down, even though it is then ordered by higher systems. At the same time Ingold’s [19] anthropological investigation into different human cultures and their interaction with their local environment draws on Gibsonian ecological psychology to suggest that the division between ecology and culture is an artificial divide. He argues that: “those specific ways of acting, perceiving and knowing that we…call cultural, are enfolded in the course of ontogenetic development, into the constitution of the human organism” and claims that cultural differences are not added on to a substrate of biological universals; rather they are themselves biological. When we combine Kay’s notion of SOHO systems with Ingold’s definition of human cultures as an integral part of these eco-systems, a very powerful proposition emerges in relation to the findings of the case study considered here. We can effectively re-frame the user’s local tacit knowledge of place, processes, culture and materials as essential and integrated ecological feedback for the design and specification of construction resources. Furthermore, this feedback and the new knowledge it provides, emerges from specific “bottom up” local situations, rather than from “top down” generic guidance that attempts to eradicate cultural differences towards materials. At present, bioregional guidance on construction resource specification, offers the most compatible approach through its fundamental recognition of the indivisibility of cultural difference and ecology.
9
Natural materiality: taking technology to the limit
A final theme to emerge from the findings concerns the nature of the materials themselves. The more natural and relatively unprocessed materials, which participants were familiar with and attached to, carried a higher emotional endearment value than more processed and composite materials such as concrete, steel and plastic which were difficult for them to place. In their overall preference for stone and wood, as raw and local materials with relatively low embodied energy, it would appear that participants tacitly recognised that the more processing a raw material undergoes, the greater it’s potential for toxicity (Genoni and Montague [20]). At the same time the findings suggest that people will “trade off” different materials for different purposes, so that the more
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processed materials are recognised for the contributions they can make in terms of their specific properties. Given the importance of emotional endearment in sustainable construction resource use, a challenge for the industry is to try and utilise raw materials with the minimum of processing while maximising their potential. This will help “close the loop” between user and specifier and contribute towards buildings that are more self-sustaining. As Norman [21] points out, the imposition of constraints can actually improve the efficiency of design. Thus, rather than continually expanding the variety of construction materials available with ever increasing overall energy costs, designers and manufacturers should concentrate on utilising the properties of raw materials as close to their original elemental state and geographical origin as possible. This implies focusing on a more limited palette of materials but working to the edge of technology in developing building elements related to these.
10 Conclusion By re-framing the debate on sustainable construction resources in terms of people’s relationships with construction materials, the findings of the case study presented here suggest a number of new themes in the discourse which deserve further investigation. These themes draw on affordance, tacit knowing and attachment as important means of evaluating the wider sustainability of construction resources beyond the current physical criteria used in tools such as LCA and ecolabelling. This can arguably best be achieved by architects and researchers considering cultural difference as an integral part of eco-systems, and removing the present dichotomy between cultural investigations of materiality in architecture and physical investigations in building science. The importance and particularity of place, as an ecological/cultural context for evaluating materials is re-asserted here through the findings and a bioregional approach to materiality is suggested as offering the best way forward at present, because it addresses this joint context. True sustainability is thus based on a deeply situated knowledge of materiality, rather than a simple physical efficiency of resource use, which stays as close to the origins of materials as possible.
References [1]
[2] [3]
Ryhaug, M., Policing Sustainability: Strategies Towards a Sustainable Architecture in Norway. Sustainable Architectures: Cultures and Natures in Europe and North America, ed. Guy, S. & Moore, S.A., Spon Press: Abingdon and New York, pp. 145-161, 2005. Kasteren, J.V., Croes, H., Dewever, M. & Hass, M., Buildings That Last, NAi Uitgevers: Rotterdam, p.8, 2002. Stevenson, F., Jones, M., & Macrae, J., Mapping Building Materials and Products in Remote Areas: Sustainable Supply Chains and the Specifier. Built Environment, 28 (1), pp.33-45, 2002.
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266 Eco-Architecture: Harmonisation between Architecture and Nature [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18]
[19] [20] [21]
Guy, S., & Shove, E., The Sociology of Energy, Buildings and Environment: Constructing Knowledge and Design Practice, Routledge: London, 2000. Morton, T., & Little, Building with Earth in Scotland: Innovative Design and Sustainability, Scottish Executive Central Research Unit: Edinburgh, p.42, 2001. Ingold, T., The Perception of the Environment: Essays on Livelihood, Dwelling and Skill, Routledge: London and New York, p.5, 2000. Kibert, C., Senddzmir, J., & Guy, G.B., ed.. Construction Ecology: Nature as the Basis for Green Buildings, Spon Press: London and New York, p.15, 2002. Kohler, N., Cultural Issues for a Sustainable Built Environment. Buildings, Culture and Environment: Informing Local and Global Practices, ed. Cole, R., & Lorch, R., Blackwell: Oxford, pp.83-108, 2003. Leatherbarrow, D., The Roots of Architectural Invention: Site, Enclosure, Materials, Cambridge University Press: Cambridge, p.149, 1993 Hagan, S., Taking Shape: A New Contract Between Architecture and Nature, Architectural Press: Oxford, p.93, 2001. Gibson, J., The Ecological Approach to Visual Perception, Houghton Mifflin Company: Boston, pp.129-140,1979. Vihma, S., Products as Representations: A Semiotic and Aesthetic Study of Design Products, University of Art and Design Helsinki: Helsinki, pp. 49, 1995. Polanyi, M., Personal Knowledge: Towards a Post-Critical Philosophy, Routledge Keagan & Paul, London, p.62, 1983. Stevenson, F., Materiality: People, Place and Sustainable Resource Use in Architecture, unpublished Ph.D. thesis, University of Dundee: Dundee, 2005. Fransella, F., Bell, R., & Bannister, D., A Manual for Repertory Grid Technique: Second Edition, John Wiley and Sons Ltd: Chichester, 2004. Cooper, I., What is the Problem? Buildings, Culture and Environment: Informing Local and Global Practices, ed. Cole, R., & Lorch, R., Blackwell: Oxford, pp.109-124, 2003. Karsten, J.V., Croes, H., Dewever, M. & Hass, M., Buildings That Last, NAi Uitgevers: Rotterdam, p.124, 2002. Kay, J.J., On Complexity Theory, Exergy and Industrial Ecology. Construction Ecology: Nature as the Basis for Green Buildings, ed. Kibert, C., Senddzmir, J., & Guy, G.B., Spon Press: London and New York, p.72-107, 2002. Ingold, T., Culture and Human Nature: An Obituary Notice. Online. www.abdn.ac.uk/chags9/1Ingold.htm. Genoni, G.P., & Montague, C.L., Influences of the Energy Relationships of Trophic Levels and of Elements on Bioaccumulation. Ecotoxicology and Environmental Safety, 30, pp.203-218, 1995. Norman, D.A., The Design of Everyday Things, MIT Press: London, pp.60-62, 1998. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Environmental impact of materials used in technical equipments: an overview on different methods L. Marletta, G. Evola & F. Sicurella Department of Industrial Engineering, University of Catania, Italy
Abstract In this paper the environmental impact of the most important materials used for the production of technical equipments in buildings is assessed. The analysis is performed according to Life Cycle Assessment (LCA) methodology. The LCA of a product is conducted by compiling an inventory of relevant inputs and outputs, and by evaluating the potential environmental impact associated with them. In the evaluation phase different impact categories are defined; normalisation and weighting are also performed to obtain a single score. All these phases, except inventory, can be carried out in different ways, according to different impact assessment methodologies (LCIA). For this reason, it is useful to compare the results provided by some of the most used methods, namely Eco-indicator 99 and EPS 2000, in order to understand how the assessment can be influenced by the choice of the methodology. In addition, three different cultural perspectives (Egalitarian, Hierarchist, Individualist) are considered when using the Eco-indicator 99 method, since this choice influences calculation and weighting processes. In conclusion, this study will provide an environmental ranking of the most important materials used in technical equipments of buildings, according to different methods and calculation hypotheses. The results will be useful for future analyses concerning the impact of technological systems in buildings. Keywords: life cycle assessment, embodied energy, materials, methods.
1
Introduction
Achieving sustainable development is fundamental if environment has to be preserved for future generations. To this aim, tools have been developed to WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060271
268 Eco-Architecture: Harmonisation between Architecture and Nature measure the potential environmental impact of products or services. One of the most popular tools is Life Cycle Assessment (LCA), a multi-disciplinary and systematic procedure which, according to SETAC, represents “a process to evaluate the environmental burdens associated with a product, process or activity, by identifying and quantifying energy and materials used and wastes released to the environment […]. The assessment includes the entire life cycle of a product, from the extraction of the raw materials to the final disposal” [1]. Another parameter useful in environmental analysis is the Embodied Energy, defined as the overall energy demand, valued as primary energy, which arises from the production, use and disposal of a product or service. Table 1 shows the Embodied Energy (EE) associated with the main materials used in technical equipments in buildings. Table 1:
Ferrous Non ferrous
Embodied Energy (EE, MJ/kg) in technical equipments of buildings. MATERIAL Steel Stainless St. Cast Iron Copper Aluminium
EE 26,7 79,9 60 72,9 164
Ref [2] [2] [2] [2] [2]
MATERIAL PVC Plastics HDPE Glass wool Insulat. Rock wool Polyureth.
EE 77,2 64,9 31,3 15,7 99,8
Ref [2] [2] [3] [2] *
*: average data for European factories.
2
How to perform the Life Cycle Assessment
According to the ISO 14040 series [4], an LCA consists of four steps: 1. Goal and scope definition [5]: the goal and the object of the analysis are defined in terms of functional unit, as well as the system boundaries. 2. Inventory analysis [5]: data are collected concerning the relevant inputs (raw materials and energy consumption) and outputs (emissions and wastes) related to production, use and disposal of the functional unit. 3. Impact assessment [6]: the environmental impact due to inputs and outputs from the inventory analysis is evaluated. 4. Interpretation [7]: the results of the impact assessment are analysed, and possible improvements are identified When performing the impact assessment, different methods are available, all of which are based on the definition of a number of impact categories, such as climate change, land use, resources consumption and effects on human health. The quantification of the effects on each impact category is performed by means of impact indicators, whose evaluation needs two different steps [8]: 1. Classification: every emission or resource resulting from the inventory analysis is associated with one or more impact categories. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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2. Characterization: mathematical and/or empirical models, taken from physics, natural science or economics, are used to evaluate the contribution of every emission to the impact categories. As an example, if the Global Warming Potential (GWP) is chosen as the indicator for the category “Climate Change”, the value of GWP for every gas released to the atmosphere will be determined. Apart from classification and characterization, other optional steps can be performed, such as normalization, grouping and weighting. Normalization is carried out by dividing every impact indicator by a reference value; this operation makes impact indicators dimensionless, thus allowing comparisons between different impact categories. Grouping involves sorting and ranking results across the impact categories, and may result in a limited number of damage categories. On the other hand, weighting means combining different impact or damage categories into a single score or index; numerical factors are used as weights, according to the importance attributed to every different impact. Due to the subjectivity of the weighting factors, ISO 14042 recommends not to use weighted results for public. Table 2:
Categories and indicators defined in the Eco-indicator 99 method.
Damage Category
Human Health
Ecosystem Quality Resources
3
Impact Category Carcinogenesis Respiratory effects Ioniz. Radiation Ozone layer depletion Climate change Ecotoxicity Acidificat. / Eutrophicat. Land use Minerals Fossil fuels
Abbr. Impact Indicator Ca. R.I. I.R. Oz. C.C. Ec. A.E. L.U. Mi. F.F.
DALY DALY DALY DALY DALY PDF · m2 · yr PAF · m2 · yr PDF · m2 · yr MJ surplus MJ surplus
The Eco-indicator 99 method
In the Eco-indicator 99 method, ten impact categories are defined, belonging to three damage categories, as shown in Table 2. Impact indicators are defined as follows: − Human health: The impact is measured in DALYs (Disability adjusted life years), to quantify disabilities and diseases caused by emissions to natural environment. − Ecosystem quality: The impact is measured through the Potentially Disappeared Fraction (PDF) of plants and species; for Acidification and Eutrophication the Potentially Affected Fraction (PAF) is used. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
270 Eco-Architecture: Harmonisation between Architecture and Nature − Resources: the impact on resource depletion is evaluated through MJ surplus, which is the amount of additional energy future generations will spend to extract resources, due to their lower concentration. Normalisation is based on the present overall impact measured within Europe. As far as weighting is concerned, three cultural perspectives are considered, which reflect different and well-defined attitudes towards environmental issues. Table 3 reports the weighting factors for each cultural perspective, together with a fourth “average” weighting set determined through a panel procedure. In the following the average weighting set will be adopted. Table 3:
Weighting factors associated with different weighting sets. Egalitarian 0,5 0,3 0,2
Human Health Ecosystem quality Resources
Hierarchist 0,4 0,3 0,3
Individualist 0,25 0,55 0,2
Average 0,4 0,4 0,2
It must be underlined that the adoption of the cultural perspective influences characterization as well as weighting. This means that, even if we use the same average set for weighting, three different results may be obtained. Further information concerning cultural perspectives can be found in [9]. Figure 1 shows the final score for materials used in technical equipments according to Hierarchist and Individualist perspective. The functional unit (FU) corresponds to one kilogram of material; no disposal scenario has been considered (cradle-to-gate analysis). Egalitarian perspective has not been represented, as the difference with Hierarchist perspective is not relevant. Moreover, the contribution of every damage category to the final score is highlighted; the percentage distribution into impact categories is shown in Figure 2 for the most outstanding cases (contributions lower than 0.5% are not shown). HH
Ferrous
Figure 1:
No ferrous
Plastics
Insulating
EQ
Ferrous
Re
Plastics
PU R
R ock w.
Al
Cu
No ferrous
PVC
49,4
3,1
Glass w.
5 ,6
C ast Fe
PUR
0,00
PVC
0,25
0,00 Glass w. Rock w.
0,50
0,25 Cu
0,75
0,50
HDPE
1,00
0,75
Al
1,25
1,00
St. steel Cast Fe
1,25
Steel
1,50
H D PE
Re
St. steel
EQ
Steel
HH 1,50
Insulating
Eco-indicator 99 scores (Pt/kg) for Hierarch. (left) and Individ. (right).
Under the Hierarchist perspective, copper is the most impactive material (1.4 Pt/kg, see Figure 1). Most of its environmental impact is related to the WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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category “Resources”. A clarification of this point may be provided by Figure 2; here it is shown that the main contribution (62.4%) comes from the impact category “Minerals”. Studies concerning the concentration of minerals in the earth crust have shown that copper concentration will lower at a rate faster than other materials, yielding concern about its extraction. Aluminium, which shows an Embodied Energy almost twice as bigger as copper (see Table 1), presents a lower score (0.76 Pt/kg); once again, the difference is mainly attributable to “Minerals”, due to the lower scarcity of bauxite in a world-wide perspective. Copper
F.F. 12,3%
R.I. 41,1%
Ca. 2,4%
Aluminium
R.I. 15,7%
C.C. 9,5%
Ca. 3,0%
C.C. 2,1%
Ec. 2,1%
Ec. 3,1%
A. E. 1,8%
A. E. 1,0%
Mi. 62,4%
F.F. 33,9%
L.U. 0,8%
Stainless Steel
C.C. 3,7%
Ec. 4,7%
C.C. 13,5%
A. E. 3,6% L.U. 0,8%
Ec. 18,7%
Steel
A. E. 2,1%
R.I. 20,8%
Mi. 9,5%
R.I. 61,1%
HDPE
F.F. 14,7% Ca. 1,6% Ca. 0,9%
Ca. 11,1%
Ca. 4,2% R.I. 19,0%
F.F. 60,3%
Ec. 2,3% A. E. 1,2% L.U. 0,5%
Figure 2:
F.F. 29,1%
R.I. 14,8%
F.F. 75,2%
L.U. 2,4%
Mi. 2,0%
PVC
C.C. 4,3%
L.U. 2,2%
Mi. 6,0%
C.C. 5,9% Oz. 4,0% L.U. 2,1%
A. E. 1,6%
Ec. 2,1%
Percentage distribution into impact categories (abbreviations in Table 2).
Stainless steel is the material with the highest impact on Human Health; it is interesting to notice (Table 4) how emissions from stainless steel production are WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
272 Eco-Architecture: Harmonisation between Architecture and Nature lower than those coming from aluminium production, apart from carbon monoxide and sulphur oxides. Table 4:
Stainless steel Aluminium Copper
Main emissions to air associated with the Functional Unit. NOx (g)
CO2 (kg)
CO (g)
SOx (g)
CH4 (g)
10,1 19,8 8
5,3 10 5,2
28,5 3,8 2
342 58 136
15,7 22,4 10,2
The environmental impact of stainless steel is far higher than steel (0.89 Pt/kg and 0.08 Pt/kg, respectively), due to the use of additional chemicals, mainly Nickel and Chrome, for its production. As far as plastic materials are concerned, High Density Polyethylene (HDPE) and Polyvinylchloride (PVC) show close scores (0.32 Pt/kg and 0.28 Pt/kg, respectively); even the percentage distribution presented in Figure 2 is similar. Unlike ferrous and non-ferrous materials, the impact of PVC and HDPE on the category “Minerals” is negligible, as these materials are not extracted from earth but produced from chemicals through industrial processes. Polyurethane (PUR) is by far the most impactive insulating material (0.4 Pt/kg); rock wool (0.06 Pt/kg) is more environmentally friendly than glass wool (0.12 Pt/kg). As well as with plastics, the impact due to the use of minerals is negligible for insulating materials. The least affected damage category is “Ecosystem quality”, whose contribution is higher than 20% only for steel. If Individualist perspective is now considered, the most outstanding result is that the scores for copper, aluminium and stainless steel are far higher than those provided by Hierarchist perspective. Copper now shows an impact which is two orders of magnitude higher than all the other materials (49.4 Pt/kg), with the exception of aluminium and stainless steel, whose impact is “only” ten times lower (3.1 Pt/kg and 5.6 Pt/kg, respectively). On the contrary, the score of plastic and insulating materials is lower. In order to understand this considerable difference, some details must be given about Individualist perspective. The main point is that Individualists do not consider depletion of fossil fuels a real problem, as the long time perspective is not relevant for them; they do not care about consequences which will affect future generations. The consequences of this assumption are manifold: -
There is no impact in the category “Fossil Fuels”; this is the reason why all of the materials with an important contribution coming from this impact category (Plastics, Insulating) show a drop in their score. The normalisation factor for the damage category “Resources”, which is the overall impact within Europe, also decreases when evaluated through Individualist perspective. This leads to the increase of the contribution within the remaining impact category, namely “Materials”.
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Due to such relevant issues, Hierarchist perspective appears to be more balanced than Individualist perspective. Even the authors of the Eco-indicator 99 method suggest that Hierarchist perspective should be used as the default one, whereas Individualist may be useful for robustness and sensitivity analysis.
4
The EPS 2000 method
In the EPS 2000 method, twelve impact categories are defined, belonging to four damage categories, as shown in Table 5. Compared to the Eco-indicator 99 method, there is one more damage category, namely “Biodiversity”, while the other categories are similar. Normalisation is not performed, while weighting is carried out by assessing the Willingness-to-pay (WTP), which is the amount of money people would pay to avoid environmental damages, from health diseases to disappearing of species. The monetary unit is named ELU. The final score is thus obtained by multiplying every impact indicator by the corresponding WTP, and is measured in ELU [10], [11]. Table 5:
Categories and indicators defined in the Eco-indicator 99 method.
Damage Category Human Health
Ecosystem Production Capacity Abiotic Stock Resources Biodiversity
Impact Category
Impact Indicator Unit
Life Expectancy Severe morbidity Morbidity Severe Nuisance Nuisance Crop Growth Capacity Wood Growth Capacity Fish and Meat Production Soil Acidification Production Capacity for Water
Person-years Person-years Person-years Person-years Person-years kg kg kg H+ eq kg
Depletion of reserves
ELU/kg
Species extinction
---
As shown in Figure 3, only “Human Health” and “Abiotic Stock Resources” provide important contributions to the overall environmental impact. Copper is once again the most impactive material (210 ELU/kg), and its impact is mainly due to the depletion of abiotic resources (99.4%), that is to say minerals and fossil fuels (Figure 4). Aluminium production turns out to be the most dangerous for human health, but stainless steel production is on the whole more impactive than aluminium, due to the high contribution of the category Resources. It should be noted that, according to EPS 2000 method, the weights attributed to extraction of copper, nickel and chrome is far higher than those associated with other metals, which explains the high score of stainless steel and copper.
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274 Eco-Architecture: Harmonisation between Architecture and Nature HH 10
EPC
39
ASR
Bio
210
8 6 4 2 0 Steel
St. steel
Cast Iron
Ferrous materials
Figure 3:
Al
Cu
Non ferrous
HDPE PVC
Glass w.
Plastics
Rock w.
PUR
Insulating
Environmental impact according to EPS 2000 method (ELU/kg). Aluminium
Copper
Life Expect. 0,4%
Life Expect. 53,5%
Severe Morb. 15,3% Morbidity 1,2% Nuisance 0,6%
Depl. of Reserves 99,4% Depl. of Reserves 28,8%
Stainless steel Morbidity 0,8%
Severe Nuis. 1,3%
Steel
Severe Morb. 4,1%
Nuisance 0,6% Life Expect. 5,4%
Depl. of Reserves 93,5%
Figure 4:
Life Expect. 16,2%
Depl. of Reserves 77,0%
Percentage distribution into impact categories.
The difference between copper and all the other materials, with the exception of aluminium, is even more evident than when using Eco-indicator 99 with Individualist perspective. As far as plastic materials are concerned, HDPE is more impactive than PVC (2.9 ELU/kg and 2.1 ELU/kg, respectively). Polyurethane (PUR) is once again the most impactive insulating material (2.4 ELU/kg), followed by glass wool (0.6 ELU/kg) and rock wool (0.4 ELU/kg).
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275
Conclusions
As shown in the previous sections, the potential environmental impact associated with the production and the use of a product or process may be evaluated according to different methodologies. Most of them follow the Life Cycle Assessment approach, but differ from each other because they adopt different impact categories and characterization is based on different models. On the other hand, a narrower perspective is adopted when using Embodied Energy, as it only takes into account the consumption of primary energy, while the effects of emissions on human health and ecosystem quality are not considered. Table 6 shows how the environmental assessment may be influenced by the choice of the methodology; the materials considered in this paper are sorted according to their environmental impact, from the highest to the lowest one. Table 6: Materials Copper St. steel Aluminium PUR HDPE PVC Cast Iron Glass wool Steel Rock wool
Environmental ranking according to different methodologies. Eco 99 (Pt/kg) 1,40 0,89 0,76 0,40 0,32 0,28 0,22 0,12 0,08 0,06
Materials Copper St. steel Aluminium Cast Iron HDPE PUR PVC Steel Glass wool Rock wool
EPS 2000 (ELU/kg) 210,2 38,9 8,0 2,9 2,9 2,4 2,1 1,7 0,6 0,4
Materials Aluminium PUR St. steel HDPE Copper PVC Cast Iron Glass wool Steel Rock wool
EE (MJ/kg) 164 99,8 79,9 77,2 72,9 64,9 60 31,3 26,7 15,7
When using the methodologies following Life Cycle Assessment, slight differences can be found. The overall impression is the same, and only cast iron shows an important variation in its ranking, becoming the fourth most impactive material according to EPS 2000 method. Furthermore, inside every category of materials (Ferrous metals, Non-ferrous metals, Plastics, Insulating) the ranking is not altered, suggesting Stainless Steel, Copper, HDPE and PUR as the most impactive materials, respectively. However, even if the ranking is only slightly modified, the distance between the scores undergoes relevant changes: in EPS 2000, the Functional Unit for Copper and Stainless Steel present a score which is orders of magnitude higher than that of all the other materials. This will yield outstanding effects if products made up of several kilograms of different materials are to be compared. Different results are provided by Embodied Energy, as Aluminium and PUR turns out to be the materials with the highest primary energy consumption; according to this approach, Copper is not the most impactive material. PUR and HDPE still represent the worst options for insulating materials and plastics, respectively. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
276 Eco-Architecture: Harmonisation between Architecture and Nature According to the results of the present study, the use of different methodologies to evaluate the potential environmental impact of products may influence the final results of the analysis. However, a clear environmental ranking of the materials used in technical equipments in buildings emerges.
References [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11]
Guidelines for Life Cycle Assessment: a Code of Practice. Society for Environmental Toxicology, SETAC, Brussels, 1993. ETH-ESU: “Ökoinventare von Energiesystemen“, Zürich 1996 Loos B., De produktie van glas, glasvezel en glaswol, 1992. ISO 14040. Environmental management – life cycle assessment – principles and framework. Geneva, Switzerland: International Standard Organization (ISO), 1997. ISO 14041. Environmental management – life cycle assessment – goal and scope definition and inventory analysis. Geneva, Switzerland: International Standard Organization (ISO), 1997. ISO 14042. Environmental management – life cycle assessment – life cycle impact assessment. Geneva, Switzerland: International Standard Organization (ISO), 1997. ISO 14043. Environmental management – life cycle assessment – life cycle interpretation. Geneva, Switzerland: International Standard Organization (ISO), 1997. Pennington, D.W., Potting., J. et al., Life Cycle Assessment Part 2: Current impact assessment practice, Environment International 30, pp.721-739, 2004. Goedkoop M., Spriensma R. The Eco-indicator 99. A damage oriented method for life cycle assessment. Methodology report. Amersfoort, Netherlands, Prè Consultants, 2001. Steen B., A systematic approach to environmental priority strategy in product development (EPS). Version 2000 – General system characteristic. Chalmers University of Technology, 1999. Steen B., A systematic approach to environmental priority strategy in product development (EPS). Version 2000 – Models and data of the default method. Chalmers University of Technology, 1999.
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Designing for longevity V. Straka Department of Architectural Science, Ryerson University, Toronto, Canada
Abstract The design stage of a building project is very important. Design impacts the site, physical massing, material selection, potential reuse, and energy performance. This paper addresses issues of durability of building systems in relationship to the life of a building. The spatial planning and systems selection during the design stage, with particular focus on the sustainability and life cycle of systems and materials, are essential to the potential to prolong the building’s and its components life by adaptive reuse or by dismantling for reuse at other location or component reuse. Most buildings are designed by current codes to last 30 to 100 years at most. This means that a building built today will consume energy and resources for the replacement of its components and for its maintenance for at least the same time span. If no action is taken today, then our environment is at risk during this entire period, if not longer. It is very important to consider the impact on future generations of what is being done today. Considerations of life cycle evaluation and costing over the entire life of the building are the only reasonable way to evaluate a project. As the refurbishment of buildings has potentially the least environmental impact, it is important to consider the implications of designing at least some elements, notably the structure, to provide flexibility and potential for alternative use. Keywords: design life, sustainability, cradle to grave, life cycle assessment, durability, adaptive reuse, component reuse.
1
Introduction
Over the past decade, severe weather conditions, such as hurricanes, tornados, storms, heavy rains, and unusual seasonal variations in temperatures have been increasing in number and intensity all over the world. A northern community in WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060281
278 Eco-Architecture: Harmonisation between Architecture and Nature Alberta which relies on a winter road for transportation of all supply was, in 2006, for the first time completely cut off. Due to mild temperatures, the earth had not frozen. Frequent news from the Arctic over the last few years confirms that the ice is melting and cracking and permafrost is thawing, endangering the life of many communities. Even people who thought in the 1990s that the notion of “global warming” was just a scare tactic by environmentalists are slowly accepting that something is happening. Climate change is not a bad dream but a reality. Scientists have also become united on this issue as all global weather models predict occurrences of significant changes, with the most impacted areas being the Artic and Antarctica. The rise in greenhouse gas concentrations are the result of all our activities on this planet, from the food we eat, to the work we do, to the comfort we take for granted in our lives and leisure activities. Canada made a commitment to Kyoto agreement by reducing its greenhouse gas emissions by 6% based on 1990 level by 2010 but, in reality, emissions have been increasing by 1.5% per year since 1990. Currently, greenhouse emissions stand +20 % over the Kyoto target. Approximately 40% of Canada’s annual national resource expenditure is consumed by the construction industry CaGBC [1]. The proportion is even larger for non-energy non-renewable minerals. In Canada, construction and demolition waste equals about 35% of the total waste stream in Canada CCA [2] representing 11mega tonnes in weight. This paper will look into possible improvements in which designers can improve the bleak statistics of construction industry.
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The design life of a building
Buildings are designed to last a certain number of years, usually as specified by codes which primarily focus on design loads. Environmental loads (snow, rain, wind, seismic) are recorded on a regular basis, some even constantly, and these measurements are statistically processed to determine the design (specified) loads with a known probability of being exceeded in any one year NRC [3]. There are three types of structures. Temporary structures are usually in place for less than a year. Regular structures include commercial and industrial structures. In Canada, these are designed for loads with a 1 in 30 probability of being exceeded in any one year and with an expected life span of 50 years. Housing is also included as a regular structure and is expected to last 30 years. The third structural type includes important buildings such as government buildings, hospitals, and schools. These are designed for environmental loads corresponding to a probability 1 in 100. However, this does not mean that they are designed to be in service for 100 years. When considering the design life of a building, it is important to distinguish between its potential life and its useful life, the latter meaning that the building serves the same purpose as it was designed for. When a building is designed to fulfil a particular owner’s needs, future needs are usually taken into consideration, but these hardly ever exceed 10 years. It is hard to predict what will happen even in five years. Our business practices have changed and will WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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continue to evolve as technology advances. Today, business can be operated from home, product support inquiry from a Canadian customer can be rooted without any problem to India, and, as a result of globalization, manufacturing operations are moved to places where the labour force is cheap. Other examples over the past decade include the drastic change in sizes of mainframe computers and the way data and information is stored. It appears that current trends demand fewer people in the office, smaller space, and less storage. There are many changing and unpredictable parameters and this is possibly why codes remain concerned with loads only. On the other hand, the document Guidelines on Durability in Buildings CSA [4] addresses design issues related to the creation of durable buildings. The selection of building components to comply with design requirements determines their service life and impacts overall durability of a building. The Guidelines are very important as they try to rationalize criteria for determination of durability and as they recognize the importance of appropriate maintenance during the life of the component. Unfortunately, this document gives recommendations only. When referring to the life of a building, it is necessary to separate permanent elements, such as structure, from elements which can be replaced. Today, many buildings have structural skeletons which are enclosed by an independent system connected to the structure. In addition, there are other systems such as mechanical (heating, cooling, ventilation, hot water), electrical, life safety, and communications, which typically have a much shorter life and which are significantly impacted by technological advancements. It is therefore necessary to consider a building as a series of systems, each having a different lifespan. The building structure with the greatest life potential will last 30 for more than years. Communications, however, may last only a few years.
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Environmental Issues
The environmental issues address the impact of a building on the environment as well as the impact of a building on its occupants/ users. 3.1 Impact of the project on the environment Any construction project has a serious environmental impact, one which spans the period of time from a site development to a potential demolition. The site development, construction process, and production and delivery of materials result in the disturbance of local ecosystems on the actual site or, due to natural resources extraction, off-site pollution, demands on energy, waste generation, and greenhouse emissions. During its life, a building demands a continuous supply of energy for heating, cooling, lighting, and water provision, and it requires maintenance. This stage of the building’s life requires the greatest amount of energy and it is associated with the largest greenhouse emissions. A typical office building (the minimum energy standard compliance) in Toronto consumes 89% (with very little variation resulting from the material selection for the structural system) of the total embodied energy during its WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
280 Eco-Architecture: Harmonisation between Architecture and Nature operational life of 60 years. Another 6.5% is consumed on maintenance over the same period Straka [5]. The initial embodied energy (related to materials and the construction process) is under 4.5%. Hence, the very simple conclusion can be drawn that all aspects of the design process must address issues of durability, minimum energy consumption, and energy efficiency. It should be noted that these figures vary depending on the climate and use of the building Straka [5]. At the end of its life, if a building is destined for demolition, the main impact is the creation of waste. Otherwise, the embodied energy associated with this process is very small, much less than 0.5% Straka [5]. The “cradle to grave” stages of a building’s life are now completed. But, importantly, there is a potential for reuse. With the process known as adaptive reuse, the building can be put to an alternative purpose. With component reuse, some of the components can be processed for reuse on another project or reprocessed materials can be created in some other form. If the building is renovated, there is considerable reduction in environmental impact related to construction material and process. LEEDTM CaGBC [1] and other environmental rating systems encourage adaptive reuse, salvage and refurbished component reuse, and use of materials with recycled content. These rating systems are largely responsible for the increasing interest in this area. 3.2 Indoor environment Buildings not only impact the environment but also their occupants. The issues associated with creating a healthy and comfortable indoor environment have been garnering increasing attention Hydes et al. [7] and are becoming a design consideration. Again it is important to note that environmental rating systems such as LEEDTM embrace these issues. In order to understand the significance of indoor environment, it is important to realize that operating a business, i.e., paying people salaries, over the life of a building becomes by far the greatest expenditure. Any additional expenditure or loss in productivity has a significant impact on the operational cost. If the total cost of a project is considered, it can be broken into three major components: capital expenditure, maintenance and operating cost, and business operating cost. It was found [6] that the ratio of capital expenditure to maintenance and operating cost to business operating cost for an office building is 1:5:200. It is expected that this ratio does not vary significantly for buildings where humans are part of the process of wealth creation. This ratio clearly points out the significance of indoor environment. If the indoor environment is healthy, occupants are comfortable, in charge of controlling their environment, connected to outside and daylight, they feel and perform better. When these conditions are present, occupants are less likely to be absent from work or be sick, and more likely to be productive. Very importantly, with proper indoor environments, it will be easier for businesses to attract and keep the best employees. Clients seem to be concerned about capital expenditure and how to decrease construction and design costs, but are not aware that these savings are not significant in the contexts of the total expenditure during a building’s life. The design cost is typically less than 10% of the capital expenditure but the design WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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team controls an outcome two-thousand-time more significant financially. This indicates that the design team has the most significant role in achieving these financial goals.
4
Issues related to durability
4.1 Structural elements The structural elements of a building are mainly enclosed and protected from weather and de-icing chemicals. If the building is constructed following the current best practices for construction techniques there are very few problems with structural elements. Therefore they are usually found in excellent condition: concrete is unspalled, steel is not rusted, and wood is dry with no signs of rot. Thus, these elements are suitable for adaptive reuse—meaning that the structure can be adapted and refurbished for new uses—or for component reuse, meaning the incorporation of used components into a new construction at a new location. It was noted that the design loads are for 30 or 100 year environmental events but this does not mean that a given structure could not last for 100 or 200 years, a relatively short time frame when considering the passage of human history. The reuse of a structure or of its components is very viable. However, there are some potential obstacles related to both reuse processes. Codes generally favour new construction NRC [3] but make provisions for buildings that do not comply with the current code. As the codes do not outline procedure to determine the suitability of a structure or component for reuse, it is up to building officials to determine requirements from the design team. Obviously, this situation may hinder the process of adaptive reuse. 4.1.1 Design strategies There are no major problems with regard to durability of structural materials if standard best practices for a specific material are followed. As mentioned before, structural elements are not usually exposed (parking garages is one exception) and therefore usually do not require any maintenance. However, there are many design issues not related to durability which are essential and which must be addressed. These are primarily related to detailing of connections between components for easy deconstruction. 4.2 Building envelope Building envelope elements are designed for lower environmental loads due to their typically shorter life span. The performance failure of any building envelope component is not catastrophic but has serious social, health, and economic issues. Leaky condominiums demonstrated the great social impact of problems related to moisture infiltration in the building envelope. These problems caused hardship to some property owners and health hazards from mould formation for others. The problems were not related to lack of performance of any of the components but resulted from the combination of architectural design, detailing, and workmanship. The design and detailing of a WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
282 Eco-Architecture: Harmonisation between Architecture and Nature building must incorporate provisions for replacement of building envelope components. Durable cladding results in savings in natural resources and energy, in waste reduction and disposal, in maintenance, and often in savings over the life of a building. The initial cost of durable components is often high, but the additional benefit is often in better performance, leading to a more favourable life cycle analysis. Premature failures lead to reduced performance which is often related to increased energy use. At the end of a building’s life, durable components may be sold for reuse. 4.2.1 Design strategies The following design recommendations are based on the assumption that each component of cladding is designed for an appropriate set of environmental loads. • Analysis of alternative systems, including environmental and deterioration analysis. • Documentation of the selection process, including evaluation criteria and life cycle cost analysis. • Design review incorporating the building envelope components. There are architectural design implications which come from the selection of a particular cladding, i.e., EIFS must have sills and overhangs. • Detailing of the building envelope. Details should go beyond the composition of a system as they are standard and well defined. The focus should be on detailing of interfaces between different components, including the overall analysis on how the building envelope details fulfill its function. • Detailing of system components for easy access for maintenance and replacement. Cladding systems often do not allow replacement of components but the entire system must be replaced (e.g., window replacement requires the replacement of the entire cladding system). Detailing should be sensitive to the issue of which tools are required for component replacement. Generally, standardization will promote replacement, reuse, and separation for recycling. • Communication and discussion of design intent to the contractor, fabricator, and installer. Knowledge of local construction practices is a very important part of the process. The very best detailed system can result in poor performance if the detail is not understood on the construction site either because the intent is not clearly documented or it departs from the local norm. • Development of the maintenance plan. 4.3 Mechanical, electrical, and communication systems These systems have by far the shortest life as they are significantly impacted by advances in technology and because many have moving components. All equipment requires regular maintenance to ensure that it performs at the optimal level. It is often necessary to replace equipment before the end of its life, either
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because the repair costs are too high or because better and more efficient equipment is available. 4.3.1 Design strategies It is very important to accommodate mechanical components in a building in the most flexible way, allowing for easy access to maintenance, replacement, and changes in technology. Obviously, a minimum amount of mechanical equipment is better and more sustainable. In contrast to the case of building envelopes, replacement costs are commonly incorporated into maintenance budgets.
5
Design issues
The most important factor in prolonging the life span of buildings and minimizing their environmental impact is the design. Architecture, spatial planning, and flexibility determine a building’s potential for reuse. The health of a building is related again to design and there are economical constraints Lucuik et al. [8]. Below is a list outlining important design considerations: • Architectural design combined with massing of programs determines a building’s shape and the surface area exposed to the environment. This impacts energy demands. Also, architectural design has a serious impact on the performance of building envelope components. • Spatial planning of a building is of utmost importance. Spatial planning determines the penetration of daylight into the interior, the functionality of passive systems, and adaptability for many potential layouts for interior use. • The structure should be designed for appropriate occupancy loads and should include potential for expansion. Around the perimeter, it should accommodate a variety of cladding system loads and include flexible penetrations between floors for mechanical/ communication services. This is very important for the future reuse of buildings. Structure is related to the shorter life span of mechanical equipment and to changes in technologies. • Detailing of the attachment of cladding to the structure should account for ease of access and replacement. • The building envelope should be detailed in a way which allows for component replacement. • There has to be a benefit, social or economical to improved design and environmental
6
Case studies
6.1 BMW building BMW’s new flagship store opened in downtown Toronto in the autumn of 2003. It is located on a highly visible site by the Don Valley Parkway (the DVP, a major traffic artery) and the Don River. The site was occupied previously by an existing 1960s steel-framed office building (which was extended in the 1970s), and was classified as a “brownfield site” requiring extensive remediation and an WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
284 Eco-Architecture: Harmonisation between Architecture and Nature environmentally sensitive area, flood plane of the Don River. Any new construction would have to abide by stringent setback regulations established by the Toronto & Region Conservation Authority and would have pushed a new building farther away from the DVP and made it impossible to retain the same visibility as the existing structure enjoyed. Thus, it was agreed to keep the original footprint and adapt the existing structural frame and redesign its exterior and interior and create an addition to house the service department. The structural system of the existing building was a one-bay steel frame with hollow precast concrete panels spanning 16 feet between the frames. With the decision to keep the existing footprint, the building was stripped down to its structural steel skeleton with precast concrete slabs. Availability of drawings for the original building from the 1960s as well as for the two-storey addition from the 1970s made it possible to identify accurately the structural properties of the steel. Visual inspection was required to confirm the actual quality and steel properties were confirmed by tensile tests. It was determined that the existing structure, though sound, would need strengthening to meet current building code seismic provisions and change of occupancy from office to retail. This resulted in strengthening of all beam column connection to act as rigid frames by welding of additional t’s or plates. Also some columns in the area of new two storey space and beams required strengthening. The project, both innovative and of high quality, was completed in just over 2 years. The reuse of steel resulted in few complications and produced little ambiguity. 6.2 MEC Mountain Equipment Co-Op (MEC) is a well-established retail company operating as a membership co-operative and supplying quality outdoor equipment and wear in Canada for over 30 years with retail facilities in 10 locations across Canada—from Vancouver to Halifax. MEC prides itself on its reputation as a “Green Company”. It adopted a corporate policy which amongst others emphasizes leadership for a just world, social and environmental leadership and strives for a healthy planet. As well as their business operations, the construction of their buildings follows strict guidelines for sustainability. Green roofs, composting toilets, daylighting, recycled/reused materials, radiant floor heating, efficient heating/cooling and energy saving measures are just some of the features found in some of their buildings. The Winnipeg project was innovative in its construction and design. The project was a collaborative effort and followed an “integrated design process”. Meetings were held and feedback from the public was sought and equally valued as that of the stakeholders. In this way the community was engaged in the importance of material reuse. Team members worked together from the very start and developed a conceptual design approach in 6 intensive workshop/design sessions. MEC’s values and goals were clear and the architects and owners worked collaboratively to achieve the “greenest” building possible. The building is located on a small parcel of land in downtown Winnipeg which had 3 existing buildings on it. It was decided to reuse the buildings as much as possible. Two of WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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the three structures were unsuitable and deconstructed, and materials found in these buildings was reused in the new building, while the remaining structure of the third building was retained and redesigned. The 960 m2 store uses a wide variety of materials—reused and new showcasing sustainable features in a modern facility. Materials not incorporated into new construction were used elsewhere (300,000 bricks were cleaned and given to Habitat for Humanity for reuse). The project achieved a gold rating from LEEDTM.
7
Conclusions
The above two case studies demonstrate two different ways of prolonging the life span of buildings. It is important to design all future projects for adaptive reuse potential, considerations of environmental impact, and underlying health issues related to a building’s indoor environment. Durability of building systems and their components is important as it conserves natural resources for replacement and maintenance and decreases the amount of waste. Besides environmental issues, durability has a serious impact on indoor environments. A leaky building envelope may result in a draughty indoor climate and in moisture retention within the walls which may support mould growth. Unfortunately, these effects are not easily measurable. During the design process, they may be neglected but they may have a serious impact on business operating costs. Economically, life cycle cost evaluations should be used to support system selection, but it is important that the analysis include other benefits associated with better performance, such as energy consumption and greenhouse emissions. Durability is very strongly associated with a building’s life span. It has very little impact on the reuse of buildings and the extension of their life beyond design life. The most important factors in prolonging building life are good design, flexibility, adaptability, and value of the building (architectural, reputation, and residual value).
8
Recommendations
It is essential to prolong the life span of buildings as this will reduce the environmental impact of construction. Very importantly, design issues have to be addressed as these have the major impact on building reuse. It is not only the architecture which distinguishes one project from another, but also the building’s reputation. Is the building “sick”? What is the quality of the interior environment? What is the potential for adaptability? Design issues are still underrated perhaps because of the insignificant cost of design and the lack of relationship of design issues to indoor environments. In order to move forward, it is essential that design issues be addressed and that clients become educated about their investments. It is important that environmental strategies are tracked and their performance evaluated, including the comfort of occupants. In order to progress in this direction, it is important that the following observations be taken into consideration: WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
286 Eco-Architecture: Harmonisation between Architecture and Nature •
•
• •
Improvement in design and indoor environment will not occur unless there is documentation which allows for evaluation of occupants and for performance surveys of buildings. It is important to educate clients that a post-occupancy survey is critical in determining the parameters for future design. It is not possible for designers to improve their designs unless they have feedback from practices they implemented in the past. As design cost is not associated with performance, neither designers nor clients who would accrue additional cost are interested in taking these steps. However, it is essential to improvement in the construction industry to define parameters related to performance, which could impact design. Improvement in design strategies for effective green buildings is related to input from performance evaluation of existing buildings. This is a weak link because there is very little information on how green buildings perform and on how they are related to indoor environmental quality. Education of clients is of outmost importance as it can assure that their goals for achievement of efficient and profitable business are met while the environmental conscious design was implemented. Designers can move forward only if they are aware how their design perform in practice.
References [1] [2] [3] [4] [5] [6] [7] [8]
CaGBC, LEED Canada NC v1.0, Canada Green Building Rating System, Canadian Green Building Council, Ca, 2004. www.CaGBC.org. CCA, A Best Practice Guide to Solid Waste Reduction, Standard Construction Document CCA 81, Canadian Construction Association, 2001. NRC, National Building Code of Canada, National Research Council, Ottawa, Ca, 1995 and 2005. CSA, CSA S478-95 (R2001) – Guideline on Durability in Buildings, Canadian Standards Association, 1995 (R 2001). Straka, V., Sustainability in Construction Industry. Proc.32nd Annual General Conference of the Canadian Society for Civil Engineering, CSCE, Saskatoon, Saskatchewan, Canada, GC-269, 2004. MacMillan, S. editor, Designing better buildings, E & FN Spon, London, UK, 2004. Hydes, K., McCarry, B., Muller, T. & Hyde, R., Understanding our green buildings: seven post occupancy evaluations in British Columbia. Closing The Loop Conference, Windsor, UK, 2004. Lucuik, M., Trusty, W., Larsson, N. & Charette, A business case for green buildings in Canada, Morrison Hershfield & Canada Green Building Council, Ottawa, 2005.
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Natural building systems: experiments in urban ecology K. Connors State University of New York at Buffalo, USA
Abstract Natural building and alternative material use have evolved gradually in the United States over the past 40 years, mostly in rural situations, often outside what Ann Cline calls the “Circle of Architecture”. With few exceptions, such as Portland, Oregon and Madison, Wisconsin, urban natural building has not taken a strong hold. The Rural Studio of the late Samuel Mockbee represents the quintessential design/build pedagogy for the socially conscious architecture curriculum in a rural setting. This paper describes the convergence of natural building, design/build pedagogy, and the support of an emerging culture of urban ecology in Buffalo, New York, by chronicling student work at the University at Buffalo. The design/build seminar course, Natural Building Systems, explores a range of alternative building materials and, through service to existing non-profit groups practicing urban agriculture, employs these materials in a participatory design/build process. Keywords: natural building, design/build, urban ecology, alternative materials.
1
Introduction
Kennedy [1] describes the growth of the natural building movement through the vehicle of colloquia, beginning in 1994 in Oregon: “The many disparate efforts to relearn ways of building with local materials and adapt them to modern needs have been brought together into a single conceptual basket with an easily understood name: ‘natural building.’” The purpose of Natural Building Systems is twofold: to introduce natural building to students of architecture and to implement design/build projects that reinforce existing urban neighborhood revitalization initiatives.
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288 Eco-Architecture: Harmonisation between Architecture and Nature The collaborative teaching team consists of the author, a local natural builder (D. Lanfear) and an Intern Architect (S. Heiser). The seminar began with only a rough outline of planned research in order to allow for improvised material research. Once clients were selected through an RFP (Request for Proposals) process, programming and design commenced in parallel with material research. From a pedagogical perspective, Natural Building Systems was conceived as both a materials and methods laboratory and a studio. It was intended to provide an opportunity for direct experience and experimentation as the basis for architectural inquiry, and aimed to utilize natural and recycled materials while facilitating community volunteers in the participatory building process.
2
Research in natural and found materials
The seminar began with an introduction to natural building concepts through images of built works and construction processes, and discussion of the activities of a design/build project. One specific focus of the seminar was the discovery through action of the properties of natural materials, especially earth as a building material. 2.1 Cob making There can be no better introduction to earthen materials than making cob. Given that the seminar began in January in Buffalo, it was necessary to acquire bagged clay and sand to create the cob mixture. A few straw bales were obtained from a local barn and the studio was transformed into a workshop. The design mix consisted of roughly a ratio of 1:3:1 (clay: sand: straw) by volume. Domestic students generally were treated to a new experience, whereas some foreign students were familiar with the ambulatory mixing process, fig. 1. The crude mixture was made into small bricks with wood reference strips to register shrinkage. They were left to dry.
Figure 1:
Cob mixing.
Figure 2:
Found material assembly.
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wall
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2.2 Scavenger hunt Besides natural materials, natural building strives to use discarded and recycled materials. Examples include Reynolds’ rubber tire Earthships, or the silo sections of Jersey Devil creations. Retrieving usable materials, otherwise destined for the landfill, demands a watchful eye. The skill must be cultivated. The first assignment of the seminar was a group project to find and assemble into a building system materials from a waste or scrap source. Students proposed all manner of compositions for wall components and assemblies, fig. 2, often using shipping pallets as a frame, with various infill materials. Aluminium cans were used to create cladding shingles, sheet metal scraps for roofing. 2.3 “A Hut of One’s Own” A single text was assigned for the seminar, a delightful book of this title by Ann Cline [2]. The hut represents the primitive and the personal, the refuge and the ritualized experience. It situates architectural experience in the process of making, and opens the world of materiality to modest, even banal, constructs. It argues, in part, for a world that is directly lived: “How, indeed, do we regain a world that is directly lived, as it was for the Chinese recluses and the desert fathers, or as it is now for some of today’s homeless.” [2]. It was precisely the open-endedness of the hut as a model for architectural inquiry that suggested it as the inspiration for the next work. 2.3.1 The de-constructable hut The second assignment called for the construction of a de-constructable hut; that is, one possessing the ability to be readily taken apart and rebuilt, fig. 3. It was to be built first in our studio space and then relocated to the project sites. Two groups were self-formed to work on two huts (for two clients, sites and projects).
Figure 3:
A transforming tool shed.
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290 Eco-Architecture: Harmonisation between Architecture and Nature The groups were given the freedom to interpret the program for the hut as they saw fit. The only prerequisite was that the two huts fit in the studio space. The unwritten assumption was that to be “huts” they should accommodate the practice of “hanging out.” However, as the process of identifying the potential clients evolved, the program for the huts transformed into utilitarian structures – tool sheds. 2.4 Papercrete In the spirit of open space, the faculty responded to a student request to experiment with papercrete (a mixture of cellulose and a binder). This afforded the opportunity to make an investigation of the properties of various binder materials. Pulverized slag (a steel manufacturing by-product) and fly ash (a coal combustion product) were donated by a ready-mix concrete supplier. All the other materials were readily available. Students self-assembled in six groups to mix various proportions of the cellulose pulp with a selected binder. They were also encouraged to experiment with multiple binder materials. A five-gallon container was premixed with a blended mash of newspapers and water. Dry cellulose insulation was also available to mix fresh pulp. Samples were prepared in small plastic cylinders for compression testing, fig.4. Since some of the binders did not chemically depend upon the water content, they required a considerable length of time to set (dry). The combinations of binder proportions varied in terms of volume or weight. The compression testing was planned for later in the term.
Figure 4:
Papercrete samples (l to r: Portland cement, fly ash, slag, Plaster of Paris, lime, and clay).
2.5 Load-bearing strawbale wall The planned research entailed the construction of an earth plastered strawbale wall and its gravity load testing. An eight-foot long by eight-foot high wall was constructed with a wooden base (toe-up) at the bottom and box-beam at the top. Two-string bales were stacked on edge – straws in the vertical direction. Fencing wire was used in a vertical loop at each end to help align and slightly pre-compress the bales between the toe-up and box-beam, fig. 5.
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Figure 5:
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Strawbale mock-up wall.
The plaster mix was from local hand-excavated clay loam. It was mixed into a thick clay slip with a paddle-style mixing bit on an electric drill. Some of this was first thinned and sprayed onto the stacked strawbales using a pneumatic sprayer with an attached hopper. This created a natural bonding agent for the earthen plaster. Straw was chopped using a mulching attachment on an electric leaf blower. The plaster was mixed by volume in the proportion of 1:2:1 (slip: sand: chopped straw). After voids in the bare wall were packed with straw and cob, the first coat of plaster was applied by hand. Due to the difficulty in obtaining clay directly from the ground, bagged dry clay was ordered for the balance of the plasters. Load testing of the wall was planned after the spring break.
3
Design/build process
One premise of a successful design/build project is that early comprehension of the whole is essential. Since the effort would be collaborative, this is necessarily a group process. Part of the first week was devoted to brainstorming a list of tasks or activities necessary to complete the design/build project. The students generated a list that was put into a rough Gantt chart. Among the activities identified was the task of managing the tasks of the whole group. 3.1 Roles of students In the second week, students were asked to choose a task or tasks on which to take initiative. As the tasks were distributed over the course of the projects, some individuals were at first freed up to participate more in the testing program. As the semester progressed, roles further evolved as teams self assigned specific tasks in the development and presentation of their design concepts. 3.2 Scheduling The original Gantt chart was followed as closely as possible. As tasks slipped in one area, other activities were moved forward to keep the process moving. As in WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
292 Eco-Architecture: Harmonisation between Architecture and Nature any complex endeavor, multi-tasking was essential. The teams were simultaneously responsible for designing their de-constructable huts, researching natural building materials and techniques, constructing test specimens and the mock-up wall, meeting with clients, and doing site analysis. As the projects moved forward, the design and presentation activities took precedence since timely client approvals were essential to the critical path. 3.3 Participation Ultimately the goal of the design/build process is to involve students with members of the non-profit organizations, neighbors and families, other members of the University community, and various levels of the city bureaucracy. This connection is an integral part of community building that has been tremendously successful in cities such as Portland. Practicing simple natural building techniques, experienced community members can move forward with additional phases of work, and become teachers of volunteers in the development of other urban natural building initiatives.
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Locating urban ecology clients
In order to optimize the design/build schedule for the semester, the process of soliciting clients began prior to the start of classes. By canvassing faculty and community leaders involved with various non-profit organizations, a list of approximately 20 contacts was formed. A draft Request for Proposals (RFP) was prepared and reviewed with the students in the first week of classes. It was issued to prospective clients at the end of the first week. 4.1 Request for proposals/evaluation The RFP was a Natural Building Systems Grant announcement. Specific requirements included legal ownership or control of land, funding for materials and fees, general liability insurance, and a community of volunteers to participate in the actual construction. Two organizations responded with proposals for projects: The Massachusetts Avenue Project, and Street Synergy Community Association. Volunteer students reviewed the proposals. They identified issues of scope and size, compatibility with natural building techniques, and the need for further clarification. Meetings with the respondents were set up. Ultimately, we determined that given the number of students in the class (17) and the merits of each proposal, we would offer two Natural Building Systems grants. 4.1.1 The Massachusetts Avenue Project The Massachusetts Avenue Project (MAP) was established in 1992 to “organize and implement projects to build and revitalize Buffalo’s West Side.” [3]. Their core programs include Growing Green, a youth oriented urban agriculture project and Food Ventures, a micro-enterprise development program. MAP occupies several connected vacant parcels and one with a frame dwelling WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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housing one of the project facilitators. MAP’s proposal included the possibility of a new greenhouse, exterior bake oven, and a tool shed to support the urban agriculture program. 4.1.2 Street Synergy Community Association Street Synergy Community Association (SS) was organized in 1999 to improve “the integrity and strength of Buffalo’s University District neighbourhoods and to improve the community’s quality of life.” [4]. SS programs include Better on Bailey, a business development and façade improvement project for Bailey Avenue, and Clean and Secure, an initiative to maintain order and cleanliness in the low to moderate-income neighborhood as a means of fighting blight and crime. SS developed a garden project at the site of a former restaurant and apartment building that was destroyed by fire. This city owned property was the focus of their proposal, which included potential projects for a garden wall, entry gateway arch, greenhouse and tool shed. 4.2 Programs/programming The two clients shared similarities in constituencies and programs. Indeed, the SS gardening program aspires to become more like that of MAP. Both need the support and leverage of positive changes, especially physical improvements, to advance the impacts of their programs. They have similar programmatic needs (gardening and agriculture) and concerns (e.g., safety and security). Coincidentally, they both involve adjacent houses that have been previously considered for demolition. In particular, the SS site has an adjacent house that, if stabilized and renovated, could provide space for educational programs, gardening support, and a working greenhouse at a relatively modest cost. The boarded up south facade is ideally suited for greenhouse adaptive reuse. From a sustainability perspective, we advocated for reuse, or as a last resort, de-construction and salvage of the components of the vacant house.
5 Planning and design 5.1 Contextual response For each client, students used aerial mapping, Sanborn maps and physical measurements to document the sites. The MAP site is a newly created common space within an established residential neighborhood. The SS site belongs to an old commercial strip flanked by residential neighborhoods in the vicinity of the University at Buffalo. The context of each was a distinct type. The students met with client representatives and developed preliminary proposals that they presented to the clients and a guest faculty member. The feedback from this presentation included clarification of the differences in the context types. The SS corner lot on the commercial strip demanded more spatial definition without compromising security. The MAP site joined three streets at the interior of the lots and suggested a place of informal assembly. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
294 Eco-Architecture: Harmonisation between Architecture and Nature 5.2 Refinement Based on the feedback from the preliminary review, the students modified the designs and prepared to make final presentations to each group. 5.2.1 MAP proposal MAP has a track record of urban agriculture at the site and articulated its needs clearly. The masterplan proposal includes a strawbale greenhouse addition to the existing frame structure, the tool shed (hut), a central seating retaining wall, a cob oven, a screen for the compost area, and a scrap iron trellised gateway entrance from each of three streets. Existing planting and orchard areas were proposed to be expanded. The first phase would include the greenhouse, fig. 6 and the transforming tool shed, fig. 3. MAP accepted the proposal and the student team began immediately planning the final design and construction document tasks for the project.
Figure 6:
MAP strawbale greenhouse proposal.
5.2.2 SS proposal The existing SS site was reclaimed from dump ground status by the action of volunteers, based on a formal garden design that was prepared without community involvement. The SS team prepared and presented two schemes for the site improvements: one based on the formal garden, fig. 7, but incorporating the adjacent vacant house; the other making a flexible internal green space and confined to the current site boundary. Both schemes create a paved surface area with a gateway entry, fig. 8, as a transition from the commercial street. The Board approved the project at its public meeting, without choosing a scheme. The first phase would include the rammed earth garden seating wall and cob or earth-bag gateway, as well as a nomadic tool shed.
6
Build
Before the spring break, one student developed a more detailed construction activities schedule. The tasks, beginning with a ceremonial ground (and coconut) breaking, carry through the first week of May 2006. This is where the real education about the thinking side of building begins.
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Figure 7:
SS garden wall scheme 1.
Figure 8:
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SS entry gateway.
Students will be responsible for developing construction drawings and specifications, quantifying and costing out the materials, assisting in the permitting process, and supporting the client with funding and volunteer participation efforts – in addition to actual construction work. The faculty will direct or negotiate assignments based on past performance.
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Discussion
A Mid-Term Evaluation was conducted to obtain feedback from the students on the trajectory of the seminar. The results were mixed with respect to the content of both testing and real world projects, some expressing the desire to do either one or the other. The hands-on exposure to natural and recycled materials was well received, as was the experience of working with a deserving and appreciative client. Natural Building Systems has demonstrated the use of natural and recycled materials in architectural education and practice. There remains the need to show the value of building in community, for the growth of architectural students and the community itself. Reflecting on the first half of the semester one student voiced concern about the aesthetics of natural building. Our strawbale mock-up was not the minimalist or computer generated surface of his training. Since much natural building work has been realized in a volunteer context, there is often a ‘folk’ quality to the finishing, and an organic formal expression. Greater exposure of natural building techniques can expand the range of building and aesthetic possibilities, and increase the range of quality of the work as a whole. 7.1 Circle of architecture Cline [2] is not alone in her willingness to investigate the borderlands of Architecture, “…a region of structures and ideas, a wasteland of heterodoxy defined simultaneously by its proximity to Architecture and its proximity to everything else.” It is this everything else which Egenter [5] claims may invigorate architectural theory through inclusivity: “Architectural ethnology WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
296 Eco-Architecture: Harmonisation between Architecture and Nature discovers that traditional societies, e.g. many tribal groups of Southeast Asia, often show very high aesthetic developments… in this respect too, the basic field of architectural phenomena has been enormously enlarged.” From the standpoint of sustainability, the borderlands are fertile regions where alternatives to a consumer building culture abound, including indigenous builders. Rudofsky [6] states, “There is much to learn from architecture before it became an expert’s art. The untutored builders in space and time… demonstrate an admirable talent for fitting their buildings into the natural surroundings.” Davis [7] notes that in reality architectural production knows no such borders: “…buildings are built in a world in which most of the various players … do not fundamentally change the way they work because of Pevsner’s distinction between “architecture” and “building.” They tend to do the same things, although perhaps to different degrees, on different kinds of buildings.” Natural Building Systems advocates the evolution of architecture out of the process of making as a necessarily communal enterprise. Belonging here to the academy, the mud buildings of 2006 will take their form from any number of influences, from Taos to The Simpsons, from blobs to hyperspace.
References [1] [2] [3] [4] [5] [6] [7]
Kennedy, J. F., Smith, M. G., & Wanek, K. (eds.), The Art of Natural Building: Design, Construction, Resources, New Society Publishers: Gabriola Island, p.3, 2002. Cline, A., A Hut of One’s Own: Life Outside the Circle of Architecture, The MIT Press, Cambridge, 1977. MAP, www.mass-ave.org. Street Synergy Community Association, Inc., www.streetsynergy.org. Egenter, N., The Present Relevance of the Primitive in Architecture, Structura Mundi, Lousaine, p.75, 1992. Rudofsky, B., Architecture Without Architects, University of New Mexico Press, Albuquerque, p.3, 1964. Davis, H., The Culture of Building, Oxford University Press, New York, p. 10, 1999.
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Promoting sustainability of earth constructed private and public buildings in South Africa G. Bosman Unit for Earth Construction, Department of Architecture, University Free State, South Africa
Abstract For many urban South Africans the traditional way of building recalls rustic images with a colourful cultural past. The self-help process of home-making in traditional materials is still strongly linked with rural earth construction. While the temporary recycled shack becomes the next housing step closer to the image of the promise of a better life in the city. In South Africa the ever growing consciousness of sustainable values resulted in some long life, low energy and lose fit buildings constructed during recent years. This paper reflects on some buildings constructed, sustainable efforts in capacity building and training on different levels during the past ten years under the supervision of the Unit for Earth Construction (UEC) at the University of the Free State. These activities of the UEC shows that by upgrading existing skills and techniques involving stabilised earth construction, economic and ecologically sustainable buildings of a high quality can be built. The social and cultural sustainability of these buildings boost local economic development and can help to revive the tradition of women participating in the home-making process. Much of the findings in this paper are based on desktop research, field studies, involvement in community buildings and the personal experience of the author in building his own home using a considerable amount of earth construction. This paper also reflects on preliminary findings from a research project funded by SANPAD (South Africa – Netherlands Research Programme on Alternatives in Development) and conducted by the University of the Free State in collaboration with the Technical University Eindhoven, Netherlands. Keywords: sustainable development, earth construction, training, community small builders, professionals, architecture students.
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Introduction
In years to come, South Africa will have to cope with the huge shortage of affordable, human and comfortable housing for its inhabitants. Against the background of a colourful history of vernacular architecture and an elaborate colonial European image, the poor will continue building temporary urban shelters constructed in rubble plastic and discarded wood and corrugated iron. High expectations from sensitive, controversial [7] and some times corrupted government housing projects, the loss of indigenous building practices, and the elusive prosperous city life contributes to an unwanted built environment [2]. The preferred building materials in South African informal settlements are mainly lightweight, recycled material. Together with rapid urbanisation and the occasional overnight relocation of these settlements, make the structures’ intransit adaptability by far more favourable than its comfort or safety. Few city dwellers will resort to a traditional way of building, if so, it is seen as temporary. Even if natural building materials like suitable earth for construction, wood, grass or stone are available, the image of building in natural material is not acceptable. Changing aspirations and loss of knowledge also result in poor use of natural materials, reducing the status of traditional buildings. There is a constant struggle between the simple and frail African technology, supported by subsistence lifestyle with natural rules and the changing new technologies with no sustainable principles in mind. Exploited for centuries, African cities were conceived, designed and built on European models, which eventually supports an American life style [8].
2 Earth construction as vehicle for sustainability During the past 10 years more than a thousand students have been trained by the UEC in the advantages of the contemporary application of earth construction techniques. These young professionals have begun to reach the market place effectively, gradually eroding some misconceptions and scepticism pertaining to earth construction in general. Architects should not only design earth constructed and sustainable buildings, but build and inhabit it as well, for they are in the position to introduce new materials and construction techniques with in their designs. The character of the soil in the Free State [7], the vernacular architecture and the climate allow suitable use of both adobe (sun dried earth blocks) and CEB (compressed earth blocks). The energy crisis of the 70’s only resulted in government endorsed projects in the 1980’s, where European building projects became prototypes of energy saving and environmental friendly construction techniques. In the early 90’s South Africa, with the support from several European Organizations, persisted in the quest to challenge a more technical, scientific and systemic approach to building with earth.
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Figure 1:
Students doing service learning classes on community projects in the production and construction of adobe or sun dried earth blocks.
Figure 2:
A Proto-type farm workers house at Glen Agricultural College, Bloemfontein and the Albert Luthuli Day Care Centre in Mangaung during construction in 1997 [3].
3
Training of young professionals
The University of the Free State was in the fortunate position to become one of a few tertiary institutions world wide to include a scientific based education programme with earth construction as part of the curriculum. The Department of Architecture is the smallest, of the six national Schools of Architecture, with between 180-200 students annually. The design programme of the school is founded on the “making of meaningful place” a universal theme being propagated by Christiaan Norberg-Schulz [10] since the 1980’s in Genius Loci: Towards a Phenomenology of Architecture. The Unit for Earth Construction (UEC) was established at the Department of Architecture in 1995. Core objectives of the UEC have been to gain experience through building projects, developing building capacity and reaching out to WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
300 Eco-Architecture: Harmonisation between Architecture and Nature communities in the area surrounding Bloemfontein, the capital of the Free State Province. Architecture students in their first to fourth years are being trained by the UEC by means of an Integrated Sustainable and Alternative Development Programme with the vernacular and rural landscape as background. In each year, 3-6 weeks are dedicated to design projects which focus on (i) earth construction techniques, (ii) climate control, (iii) appropriate structural systems, and (iv) recycling of building material and structure [2]. Training of not only Architecture but also Quantity Surveying and Construction Management students, established the Unit for Earth Construction (UEC) as one of the leading institutions in Africa [1].
4 Training of community builders The UEC has focused on training on different levels. The completion of 8 small to medium buildings completed since 1996 gave the opportunities for training small scale community builders. The cooperative and collective patterns of organized labour [11] are a well established custom in South Africa. Between 1996 and 1999 a prototype farm workers house, two humble day care centres and 3 ablution blocks were constructed with lime plaster adobe and compressed earth blocks.
Figure 3:
Brickyard activities in 2002 at the Mangaung University Community Partnership Programme (MUCPP) in Bloemfontein [3].
Between 1999 and 2005 an economic development centre, a school hall and a craft and tourism centre was constructed with the help of the UEC. Through these projects 170 male and female small builders have been trained in the production and construction of either adobe or compressed earth blocks. The staff of the UEC (two colleagues and the author) has been part-time involved in all of these projects dividing time on site and lecturing duties at the Department of Architecture. During the past projects the UEC has learnt a lot from the expectations of communities. Many of the community training programmes since 1996 that focused on the production and construction with earth components have been WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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greeted with great enthusiasm and commitment but resulted in only a few small brickyards becoming sustainable. New groups with no business financial history always have problems establishing small loans. Often these discouraged trainees and beneficiaries have moved on to greener pastures – leaving few survivors behind [2].
Figure 4:
MUCPP-brickyard activities with the Economic Development Centre in the background, 2000-2002 [3].
Figure 5:
MUCPP-activities in 2005 at the Economic Development Centre, Mangaung, [3].
In South Africa there is a growing awareness to test a building’s sustainability regarding social, economic and environmental aspects. The Sustainable Building Assessment Tool (SBAT) is a South African developed system used by the Council for Scientific and Industrial Research (CSIR), Academic and Technical Universities in South Africa. This also proofed to be a useful tool for architects, building managers and informed public addressing sustainable issues [14].
5
Sustainable environment versus economic development: the struggle for survival
The difficulty for communities to manage and maintain buildings is a common phenomenon in South Africa. It is almost impossible for these communities to contribute time, labour, and imagination to the management and maintenance of community facilities. In most cases the communities, especially in poverty WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
302 Eco-Architecture: Harmonisation between Architecture and Nature stricken rural areas, are poor and cannot achieve these aims with limited resources. In addition, many people hold the view that support from the government is mandatory as part of the process of income re-distribution that has been promised for years [9].
Figure 6:
The five different research areas of the SANPAD project.
The UEC is currently in the third year of a research project funded by The South Africa Netherlands Project on Alternative Development (SANPAD). The title of the research project is: A South African Building Renaissance Acceptability of sustainable, high quality, earth constructed, public and private buildings to support local sustainable economic development. Seven locations in five different research areas (north east of Bloemfontein and north west of Kimberley), all nearby former homelands, have been targeted in the Free State, North-West and the Northern Cape Provinces. A Survey was conducted with Questionnaire 1 (with a total of 1800 participants) on the acceptability of earth constructed houses within this mainly rural environment. We can confirm that the general public mostly prefer burnt brick walls for their own houses. The main reasons: “It looks good! The Material is strong and safe”. The people (78.2%) that live in an earth constructed house claimed to have made the blocks themselves, with the help of a friend or a family member while 21.8% paid for it. Of the 9 semi-formal and 13 informal brick yard owners in these research areas, producing mainly cement stabilized concrete blocks or substandard burned clay bricks, 90.6% will be interested in learning to produce other kinds of bricks or blocks. It is clear that there is a need to expand the type of products in these brickyards. These brick yard owners (96.9%) confirmed that they also would be interested to attend workshops in order to learn how to make WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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compressed earth blocks (CEB) and stabilized adobe. The training in technical and management skills of this local trades can increase the number of blocks and bricks produced, which currently varies between 2 500 and 15 000 blocks per person per month, with at total number of bricks and blocks at 387 000 per month [12]. Table 1:
The question results on the SANPAD Questionnaire 1: Choose the two materials you prefer most for building your walls.
Material indicated zinc bricks cement blocks adobe wood wood & earth
First choice 6.0 % 59.6 % 29.6 % 3.2 % 0.0 % 0.0 %
Second choice 5.0 % 32.7 % 52.9 % 3.9 % 0.0 % 0.6 %
The UEC will complete workshops with a follow up survey, by July 2006 in these areas, targeting decision makers (traditional chiefs, councillors, small builders and brickyard owners) and present an outreach community theatre production to school children and the public at large. This dramatized performance will reflect on the low status of traditional earth building and focus on the many advantages of living, and building your own house in an upgraded eco-friendly earth building technique. The main research question to be answered is: How can earth construction be more effective and acceptable in providing private and public buildings to local communities in support of sustainable economic development? During the dissemination of this project it should be clear if a technological intervention in the form of training can make and impact on the acceptability of earth constructed buildings. If the local brick yards in these areas can provide new improved earth products, it can change the acceptability of earth building in these areas.
6
Sustainable thinking
Working with earth as the primary tool to promote sustainable thinking, results in various problems. These problems with earth buildings can be grouped under the following: 1) Mechanical performance 2) Standardisation to comply with local authorities and financial institution 3) Social acceptability (high expectation) [3] The combined knowledge of experienced scientists, soil technologists, builders and architects, gained over the last three decades, contributes to the increased utilization of earth. The mechanical performance of earth used for WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
304 Eco-Architecture: Harmonisation between Architecture and Nature construction will be in question for years to come. Convincing publications on this issue not only helped the scientific community to take stock of this area of study, but also react to the high expectations of the non-scientists’ desire to understand the issues [6]. Earth construction was prohibited in of the South African towns and cities as a result of by-laws and conditions for loans set by financial institutions. This resulted in earth construction being reduced to mainly rural areas. However earth construction made a comeback after the Second World War when it was again extensively applied by many farmers who either knew the techniques of earth building or learnt them anew [5].
Figure 7:
Bosman Residence with the application of stabilized adobe and compressed earth blocks in the residential area of Westdene, Bloemfontein.
Unlike many other developing countries and some European countries, South Africa still does not have national standards for Earth Construction. However approval for earth building systems can be obtained through a time consuming process, no standard earth building blocks, bricks or components are commercially available in South Africa. Unfortunately, the communal small WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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scale of earth construction makes standardization difficult. This is, however, not a big obstacle as the contemporary earth buildings in the urban environment stand witness to. Standards are however, required by the decision makers, the financiers, and the builders. In South Africa there is not only a need for low-cost building in alternative and sustainable construction methods but also for high profile buildings in the urban context [7]. Despite the absence of accredited standards and regulations the author took up this challenge and constructed his own earth house built in a post Anglo-Boer war (1899-1902) residential area of Bloemfontein. The selective use of compressed earth blocks and stabilized adobe in this small 180 square meter house is an attempt to address the status of raw earth as contemporary building material in an urban context. With some effort even the local authorities and a financial institution were convinced and approved this technology in the centre of Bloemfontein. The Bosman residence is a second dwelling on a residential stand. In order to support the densification of the urban residential area of Westdene, Bloemfontein, a specific brown field structure was utilized. The criteria included using recycled material on site and the use of compressed earth blocks from an abandoned brickyard. A specific morphology in terms of character, volume, material and geometry was achieved. The use of plaster and paint (with colour trends from the context) and an inverted corrugated roof were in direct reaction to the existing character of the suburb of Westdene. However, a contemporary building, it attempts to blend into the context by using compressed earth blocks and adobe, while creating a high quality economic and ecologically sustainable building [3].
7
Conclusion
With a global network on earth construction in place for some decades now, the international community can share experiences, disseminate research findings and give advice. This support system confirms the growing rediscovery of earth as building material [13]. International as well as national workshops and conferences focused on some or other sustainable issues have converted many South African politicians, building professionals and students to the use of earth construction. The environmental friendly contemporary buildings that have been built in the past decade are the evidence. A bigger challenge still awaits the South African building industry, where more sustainable high profile buildings have to be constructed in order to have a substantial effect on the social, economic and ecological environments. The promotion of upgraded earth construction on our beautiful open plains and in our cities will continue, in order to change the image of building in earth.
References [1]
Bosman, G., Teaching Earth Architecture at the Department of Architecture at the University of the Free State: Current situation, WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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[2] [3] [4] [5] [6] [7] [8]
[9] [10] [11] [12]
[13] [14]
Analysis and Perspective. Unpublished Thesis: Ecole D’Architecture de Grenoble, DPEA Architecture de Terre 1998-2000, pp. xv-xx. 2000. Bosman, G., Sustainability, involved ability, and the struggle for survival. Leading Architecture and Design, vol. September/ October, pp. 22-23, 2003. Bosman, G., Teaching Earth Construction in the Free State: 1995-2005. Proc. of the 4th Conf. in the series Sustainable Built Environment, South Africa: Pretoria, pp. 38-51, 22-24 June 2005. Dayaratne, R., Earth architecture for contemporary living: prospects and new initiatives. Open House International, vol 28 no 3, pp 23-33, 2003. Gerneke. G., The return to earth: The last of three articles on earth building. Architecture SA vol July/August pp. 40-44, 1992. Houben, H., Guillaud, H., Earth Construction: A comprehensive guide. Intermediate Technology Publications, London, 1994. Jooste-Smit, P., Earth Construction: A changing tradition. Acta Structilia, 5(1&2) pp. 55-80, 1998. Jordaan, G., Sustainable Urban Future – Cleaning up a messy Past. Proc. of the Conf Sustainable Buildings & Integrated Design, South African Solar Academy, South Africa: Johannesburg, p. 329, 9 – 14 September 2002. Noero, J., Unpublished Workshop presentation: Seven reasons why community asset management will not work. Community Asset Management (CAM) Workshop 15-16 September 2002. Norberg-Shultz, C., Genius loci – Towards a phenomenology of architecture. Academy Editions: London, pp. 5 – 30, 1984. Rodriquez, A. & Pettus, K., The Importance of Vernacular Traditions. APT Bulletin. vol. XXII no. 3 p. 2. 1990. Steyn, J.J., The role of small local brickyards in economic development: a case study of Botchabelo, South Africa. Proc. of the annual Conf. of the Regional Studies Association, eds. S. Hardy, L. Larson & F. Freeland, Seaford: UK, pp. 10-12, 2004. Watson, L., Earth as a British building material. Architectural design, vol 67 no. 1&2 pp. 87-89, 1997. CSIR, www.csir.co.za/boutek.
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Section 5 Natural technologies
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Heteronomy and (un)sustainability of essential technical infrastructures A. van Timmeren1, 2 1
Climate Design & Environment (CD&E), Delft University of Technology (TUD), Faculty of Architecture, The Netherlands 2 Atelier 2T, Haarlem, The Netherlands
Abstract The methods and techniques applied in present-day essential infrastructures for energy and sanitation supply may be considered traditional and driven by the separation and centralization paradigm. There is physical expansion and this is a structural phenomenon because of globalization combined with the liberalization of the energy market and – to a lesser extent – the solid-waste market. Moreover, there is growing heteronomy of the essential utilities, particularly energy and sanitation. There is a considerable increase in the electrification of society. For solutions to new or existing problems, technological development is following the “roads present”: the existing paradigm. Strict rules and regulations often make this necessary. Changes, innovations or adaptations within these essential (infra)structures follow the principles of the quasi-evolutionary model, while during the last few years developments have more and more arisen from the endogeneous point of view and a certain kind of “techno-fix” cannot be denied. Little or nothing is done about the underlying causes of the environmental problems, whereas unforeseen side effects occur, e.g. a large amount of strongly polluted sludge in waste water treatment. Many relevant participants do not seem to realize that other, more sustainable alternatives can be found by abandoning the specific characteristics of the traditional paradigms rather than following them. This paper emphasises the potentials for sustainability and resilience in case of a reciprocal relation between centralized and decentralized systems and the interconnection of energy, waste and wastewater solutions. Keywords: heteronomy, infrastructures, autonomy, integration strategy. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060311
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Introduction
Where the essential infrastructures are concerned, the liberalization of the markets shows that the goals set cannot always be accomplished in an integral way. At a national level, there is (still) too little grip on the developments. The demand for supervision or rules at a supra-national (European) level is being heard, and this causes one of the two main reasons for this liberalization to be surpassed. Changes in technological choices and in the framework are based on political decisions and (market-driven) sectoral strategies. This asks for target values and conditions to be formulated. Market participants have no interest in overcapacity, which puts pressure on the reliability of supply (by a maximum bid on the available capacity). Pressure can also be put on the other long-term interests, including maintenance of grids and investments in, research into or application of innovations (other techniques, other subsystems or even other (infra)structures and technology). Other aspects (for the users) are sustainability, a guarantee on supply and processing and affordability. For sectors that are left to market forces, positive effects are soon to be expected on the efficient use of the (infra)structures by oligopolistic market types, and, thus, on the affordability of the accompanying services. There will be a (well-known) dilemma between the short term (economic efficiency) and the long term (sustainability and guarantee of supply). In the Netherlands, the contributions to energy independence and knowledge infrastructure of the country are tasks for the government, or, in other words, a “the public interest”. Nevertheless, it seems reasonable that the dominant market participants also subscribe to these strategic targets, or at least facilitate them. Politics still aims too much for certainties and guarantees in advance. Given the nature of the changes (particularly in the internationalizing markets), politics should pay more attention to the uncertainties and, consequently, to the question of how public interests can be prevented from getting stuck in case of unforeseen and undesired developments. Convergence is a new characteristic of the various technical infrastructures. It results in greater complexity and more dependence on the structures as perceived by users. Reliability and – in an indirect way – affordability gain more importance. At this moment, this is still at the expense of sustainability. This may be overcome by including sustainability, via reliability, as an added value at relatively little cost, e.g. in the form of a decentralized backup. Too little advantage is taken of this subaspect of sustainability. For small-scale users, this results in a simpler arena, particularly where the number of parties is concerned with which contracts have to be signed. Other characteristics of development according to the traditional centralization paradigm of the essential technical infrastructures are: specialization and segmentarization, with one or several dominant parties per subflow or sector as major results. The dominant participants have an interest in using existing structures as efficiently as possible and in developing them further with as few risky investments as possible. As yet,
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the cost of transport (distances) is not taken into account, and there is little product differentiation. As a result of the increasing importance of flexibility, sustainability and certainties, it is evident that the call for solutions according to the present “integral” approach (with the aid of a source-focused and preventive policy as an important condition for all built-up areas) adds too little value as either a process guiding or process following interpretation. With administrative-organizational “integralness” as a starting point, there is too much focus on the advantages of business economics resulting form horizontal or vertical integration. “Integralness” is used too often and, as a result, is becoming a container notion, possibly even an empty paradigm. The current paradigm, specified by the participants connected with the essential flows and infrastructures, seems to aim at a development following the principle of the “economies of scale”. In addition to more far-reaching interconnection, this implies a vertical integration building on administrativeorganizational integralness. In this process of interconnection and integration, the aspects discussed, viz. certainty and sustainability, will eventually be normative for a well-considered choice of interpretation. Here, the so-called physical integralness will be of increasing importance. The presented research tries to demonstrate the need to include interdisciplinary approaches to the integration of strategies for raising public awareness, marketing of the different qualities of water (cascading) and energy (exergy), and establishing a service business for building and operating more decentralized installations. The general aim is the integration strategy for water management and sanitation (healthy wastewater and waste streams) together with energy-generation at scales nearer to users or residents. On the one hand it comprises direct linking of building and urban settlement with their surroundings and/or (green) hinterland. On the other hand with neighboring subjects like agriculture (especially urban farming), aquaculture, horticulture, health care and food security. The research has been commissioned by the Delft University of Technology (TUD) as part of the DOSIS (Sustainable Development of City & InfraStructures) project recently continued in CD&E – Climate Design & Environment – research to investigate and develop decentralized sanitation, energy and reuse technologies. The aim is to research the spatial, social and environment related consequences of the implementation of decentralised technologies, and to define the conditions within society, with emphasis on urban planning and building.
2
Heteronomy and the effects on sustainability
2.1 Sustainability of the essential technical infrastructures It is important to distinguish between underground and aboveground infrastructures. As yet, there is little knowledge of environmental costs of the technical, often underground, infrastructure. It is not known how the WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
312 Eco-Architecture: Harmonisation between Architecture and Nature relationships between the infrastructure inside the building, and the infrastructure systems outside the building and in the area in between can affect the environmental effects (or environmental costs) as a collective process. Since much is known about the sustainability of the infrastructure and facilities at the level of the building, it has been decided to test the environmental costs at the next levels, i.e. the ones higher than this smallest relationship. In this case, this is the level of the (city) district and/or neighbourhood. For the visualization of the environmental load of a prototypal reference project, this research studies part of the development Oosterhout in Nijmegen (the Netherlands). The modelling and calculation program Greencalc was used, that translates the environmental load into environmental costs. In this new housing estate (finished in 2001), the environmental load of the technical infrastructure (excluding roads) is 10.4% of the total environmental load. This portion may be considered non-significant, but at the same time it is not to be neglected, particularly where the hot-water infrastructure and sewage infrastructure are concerned. In three alternative configurations of the reference case of Oosterhout, it turned out that a reduction of the technical infrastructure of heat supply (which was the one with the highest environmental load) at the level of the district did not automatically lead to a lower total environmental load of the district. An example is the configuration based on a natural gas grid with individual heat supply (boilers) instead of the shared heating grid. The alternative configuration using heat pumps did produce a (slight) reduction of the total environmental load. In general, the calculation of environmental costs of the technical infrastructure of this new district in Nijmegen and the related techniques prove that the smallest amount of environmental load occurs in high-efficiency heating systems with generation close to the user. More important, however, is that reductions based on optimized urban development structures have a larger effect on the environmental load than optimizing the infrastructure using other system or transport options. Hence, optimization of central utilities or other facilities demands “compact building”. 2.2 (Further) preservation Looked on from the social aim of “sustainable development”, the path of expansion selected is not necessarily the optimum as perceived subjectively. A characteristic of expansion is the increasing importance of relocating the material and energy flows. In this, physical infrastructures play an important part. They are the bases for the supply of processes, products and services that meet the fundamental needs. Building infrastructure almost always implies slow and large-scale processes in the “underground” layer. For a structural solution and preservation, the technical infrastructure should be considered, as the lowest layer in this model of layers. It will be leading for the design and the allocation of the faster dynamics of the overlying layer: the layer of the “networks” and that of “occupation”. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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The infrastructure strongly correlates with production (supply as well as drainage). A change desired in the infrastructure, e.g. a bottleneck with respect to capacity, can be solved by investing in extending the infrastructure (now often accepted), but often also by adapting the “production” in strategic spots of the (central) grid. One possibility is connecting or disconnecting (decentralized, additional) sustainable subproduction (generation or processing capacity). This may imply a gradual change of the paradigm, following a sliding time scale rather than a radical change at a certain, perhaps unexpected, point in time. Moreover, it may involve short-term interventions for long-term guarantees (sustainability, guarantees for supply or processing and affordability). Such a principle may be useful as a kind of fall-back scenario for, for example, a serious and unforeseen dysfunction of the current process of further scaling up and liberalization of sectors. 2.3 Introduction of decentralized systems There are clear differences between the characteristics (or rather: advantages and disadvantages) of the various central networks, in the energy and sanitation subflows each as well as between the energy and sanitation supply as a whole. They are caused by different “central scales” of application and different extents of visibility, but also by the management structure and the presence or absence of liberalization processes. The increasing heteronomy observed in the so-called “essential” networks and accompanying managing parties for end users does not only hold for central networks, but also for decentralized or local systems. The difference lies in the consequences of catastrophes and the extent of visibility (the subjective perception) of the results of this heteronomy for the end user. There is a common consensus in society about the necessity of fundamental facilities for meeting the most fundamental needs in the own living environment, viz. “Maintenance”, the so-called primary necessity of life. The availability of energy and food, including clean drinking water, and the removal of waste are parts of it. It is no use trying to introduce sustainability measures that harm this fundamental need. It has turned out that the ongoing processes of liberalization have put pressure on the importance of the certainty of supply, and sometimes also removal. Working certainty of supply and independence out in further detail seems necessary, or even essential, not only for further development based on the future of scaling-up (“economies of scale”), but also for decentralization (“scale economy”). The distance created between the (environmental) problem and its solution leads to more and more complexity. The process of changing the interrelated public and private services, systems and infrastructures is becoming more and more complicated and less and less predictable. Together with the increased scaling, the interconnection of the various flows and the growing number of parties and techniques involved has increased the end users’ (consumers’) (subjective) dependence. This asks for a simplification of the processes, products (or rather: services) and parties involved. A larger concentration on integral provision of services, or, in other words, the supply and management of integral WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
314 Eco-Architecture: Harmonisation between Architecture and Nature packages, offers possibilities. Also the level of application should attune better to the lifestyle and direct surroundings of the users. The ongoing individualization more and more often leads to a pursuit of decreased independence on public infrastructures and the wish for decentralized utilities (connected or not), with autonomy of the individual or the household as an extreme version. A decentralized system must not be characterized as a static system, since there is an ongoing change of an existing situation. The scale level of a decentralized system is relatively fixed. It depends on the technique of the administrative body itself, the context and the position of the observer. Technical (de)centralization concerns (a change of/in) systems. In the case of administrative decentralization, there is a distinction according to the nature of the administrative bodies: territorial decentralization (between/carried out by Government, Province and Municipality) and functional decentralization (within the Municipality). As for technical decentralization, the various flows have different definitions of (the scale of) subclusters and of “decentralized” subnetworks and subsystems. Often, there is vagueness even within the various flows. The scale level is considered decentralized, but is defined in a relative manner too often. Regarding technical decentralization, this paper starts from the production and processing of the various flows closer to the users than is usually done, with the flows being fed back to the users in a direct way. In administrative decentralization, the “sandwich strategy” may be a good starting point for the far-reaching support of making the various (infra)structures within town and country planning sustainable and possibly independent. Decentralized initiatives to solutions and environment-friendly behaviour are emphasized here. Because of the relative new market of (technical) decentralization, “niches” can be created. It has turned out that this has happened before in history. Often, niches cause a set of instruments to be developed for the start of a new paradigm or system of techniques. With the aid of strategic niche management, innovations are implemented in this type of “sheltered area”, tested and evaluated. It is possible that the creation of niches can also take place in a planned way. This is called “strategic niche management”. The difference with the more familiar principle of “pilot projects” is that a shelter is built around the new technology in the case of strategic niche management, through which the technology can develop from prototype to an actually applicable technology. Eventually, the technology should work without any protective measures at all. Generally speaking, the two main problems in decentralized solutions are scepticism of the leading (often dominant) parties involved and the larger influence of a fluctuating flow size. The former is particularly caused by responsibility (certainty) and liability. This scepticism will increase because of the necessary transition of the market(s) from supply of products to supply of services. The aspect of the flow size (in fact, the basis for the technical “economies of scale”) can be met locally by modern techniques of control and tuning, the so-called “Real Time Control”, and the subdivision into parallel facilities. Thus, the remaining main points of interest for improving the WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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competitiveness of decentralized systems and actually achieving the advantages for the environment and the users are the organization and implementation of maintenance, exploitation, provision of services and inspection of the various systems, together with the availability of backup provisions if necessary.
3
Alternative network geometry
3.1 Introduction For the essential (technical) infrastructure, the dynamics of non-simultaneous, slow transformation necessary for attuning the complex structures of society, the “flows” and nature (or natural processes) implies that it is wrong to still think in separate systems within integral development processes. That is, since there is an increasing interconnection and interdependence in the technical infrastructure of the essential flows. This does not concern local interconnections only. In fact, the total human system all over the world is linked with the issue of to what extent the increasing rate and complexity of change is integrated in a determined effort. Two development processes concerning decentralized technology for the purpose of autonomy have come forward as topical: viz. first, the efficiency and improvements in the integration of subtechniques and co-ordinated, connected concepts, and, second, a better harmony between supply (input) and demand of the (different) subflows. Additionally, there are two more general underlying development processes. The first is the environment-technical, environmental and, to some degree, also social optimization of decentralized systems within semi-autarkic projects. In spite of the potential of the underlying optimization principle of the “scale economy” claimed in much of the literature, and in spite of its importance, which was also proven, it has only been applied to a small extent. Consequently, there are not many “economies of scale”. However, the subaspects concerning the application freedom and environmental integration (smaller sizes, fewer secondary demands, etc.) and user-related demands (comfort, ease of use, costs, etc.) do improve noticeably. The second underlying development process concerns the link to economic applications related to the surroundings, often determined by soil or users, including taking nutrients back to agriculture and other lateral applications or possibilities, such as car-sharing systems. In addition to the possibility of other types of use of (agricultural) grounds (urban agriculture), the link to agriculture may not only lead to a structurally different infrastructure (aboveground and underground), but also to different country planning as a whole, when applied on a larger scale. This offers points of departure for interrelating “red” and “green” functions in environmental planning. Here, the aspects of vicinity and comfort are leading. In this situation, the search for an optimum scale of autarky or autonomy of the various essential subflows in the built-up environment gains higher importance.
WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
316 Eco-Architecture: Harmonisation between Architecture and Nature The changed network philosophy described as desired has far-reaching consequences for the way in which these infrastructures are designed and integrated. For complex systems, the coherence with which and the way in which dynamic processes are dealt with determines the translation to physical “integralness”. It is important to establish that the stability or resilience of networks is directly related to their complexity. It is not the components of the various structures that matter, but the way they are organized together as intelligent structures. It is important to learn from the organization structure and topology of existing adaptive, complex structures. Recognizing the structures of each network is needed for combining their optimally ongoing development, possible decline and damage done to them, whether desired or not, with constant or increasing sustainability and certainty guarantees for users. 3.2 Decentralization for the purpose of scale invariance In current central infrastructures of energy as well as waste water flows, the possibilities of an alternative network layout are not or not sufficiently taken into account. More and more connections are made between the various (national) networks and subnetworks in gas and electricity networks, but this occurs because of considerations of capacity and economic (business) perspectives, rather than on the basis of the principle of network geometry. Consequently, there is a direct interest for large-scale central networks to have subsystems as a decentralized cluster included into the complex network. Because of the principle of self-organization, it also offers the possibility and the guarantees for being able to make local decisions with respect to, for example, further-reaching sustainability without abandoning the principle of scale size (“economies of scale”). Procedurally, it implies that authorities and (public) grid managers may abandon policy aiming for a fixed ultimate goal. Systems within decentralized planning concepts may lead to networks, complex or not, with a more strongly decentralized network structure with part of the networks performing relatively autonomously. These may support flexible planning concepts in town and country planning. Moreover, the issue of a more precise attribution of (network) costs to specific customers or transactions (which become more and more important as complexity decreases with ongoing liberalization) may be solved or may easier be solved. Concepts as such which support increasing flexibility can anticipate changing market developments. Moreover, it causes smaller investments with fewer risks in liberalized markets. The effect of scale size by various technological developments has decreased the last 50 years, because of the low energy density and little purification efficiency per m2. This is also because improvements of energy transformation techniques and waste (water) transformation and purification have had relatively more influence on small-scale systems. The main technical advantage of (incorporating) decentralized systems is that, because of the scale size, the flows transported, processed or generated can be separated more easily into various qualities at source. In addition, the transport, the treatment, the use and/or the WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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processing per subflow can take place more efficiently according to exergetic principles, such as cascading, where further optimization against user specifications becomes possible. A disadvantage is the difficult organization, maintenance, exploitation and inspection. The development of (legal) conditions with respect to responsibilities and periodic inspections is crucial for (decentralized) systems and determines a successful penetration of this technology. Decentralized and local (sub)systems as parts of complex networks will possibly play an important role. It is important that each of the regional systems is connected “aristocratically” within higher scale levels, according to the principle of overlap as described in Christopher Alexander’s ‘semi-grid axiom’. Network relationships support a process of so-called mutual innovation and, consequently, reduce the distances between central and decentralized solutions. In addition to this, there is the advantage of vicinity facilitates the “face-to-face” interaction and horizontal communication. In order to accomplish the desired shift to a larger interest in future value and power of correction, small, gradually changing innovations should alternate (incrementally) with top-down innovation. It is a problem that particularly the innovation related aspects come off worst because of a lack of control and grip, together with the aspects of maintenance and sustainability, in the current or intended liberalized situation of different essential subflows. The alternation of incremental and structural innovation appears to be the key to work out conflicting interests coherently for the short and the long term, without this leading to concession-driven solutions which are now quite common, and which lead to sustainability disappearing more and more or becoming only a fake type.
4
Conclusion
Redesigning large parts of the primary process in a top-down manner is necessary for the implementation of the substantial structural and sustainable improvements. Within the alternating process of incremental and structural innovation that was suggested above, the incremental innovation should shift more to solutions which follow the principle of subsidiarity of the European Community (Subsidiarity is the idea that matters should be handled by the lowest competent authority). It will lead to the desired larger differentiation in quality when there is less involvement, and it will support the main starting points of the European Community, and also (literally) the starting points of the wish for liberalizing the various utilities within the European market. Establishing the incremental innovation from the lowest scale levels may be a method for solving another topical problem on a European level, viz. the creation of equality for all member states, or, in other words, the accomplishment of a “Level Playing Field”. In the set of demands of optimum flexibility, a smaller scale can guarantee better flexibility and units that are exchangeable to a larger degree. As a conclusion, it can be stated that differentiation and flexibility in the area of town and country planning are preconditions for being able to anticipate WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
318 Eco-Architecture: Harmonisation between Architecture and Nature uncertainties in the long term. Additionally, it is easier to anticipate dynamic developments that are characteristic of today’s society. The process of urbanization and the infrastructural transport and distribution systems of the essential flows should be prevented from developing in separate ways. A sound, integral (Eu)regional planning based (first) on a combination of conventional (central) systems and additional decentralized systems (or, actually, the other way round), can prevent the risk of a possible “deadlock” of the current central systems, with all the accompanying health risks. The philosopher of culture Tom Lemaire claims “what matters is finding the right ratio between the global and the local. Local aspects should not be wiped out by globalization, but should get a new place”. The strategic or random integration of decentralized clusters into the growing central networks, that approach autonomy as much as possible, will contribute to the increase of the robustness of these central (complex) networks, provided that the other conditions of scale invariance are met. Thus, it seems that the developing directions of “economy of scales” and “scale economy” need each other according to the principles of mutual interdependence.
References [1] [2]
[3] [4] [5]
[6]
[7]
[8]
Alexander, Ch. The City is Not a Tree. Architectural Forum. nr.04 & 05 / Design. nr.02. 1965. Frey, H.W. The search for a sustainable city. An account of current debate and research, PLEA 2004, The 21st Conference on Passive and Low Energy Architecture. Eindhoven University of Technology. The Netherlands. 2004. Moet, D. Autarkie. Zelfvoorzienende woonwerklandschappen. Park. Haarlem. The Netherlands. 2004. McDonach, K. & Yaneske, P.P. Environmental management systems and sustainable development, The Environmentalist, vol.22, pp217-226, Academic Publishers, Kluwer. 2002. Timmeren, A. van. The scale of Autarky; self sufficiency through integrated design of decentralised natural technologies in city districts and building clusters. Proceedings Sustainable Building 2002. Oslo. Norway. 2002. Timmeren, A. van, Kristinsson, J., Röling, L.C. Existing infrastructures: a restriction for real sustainable development, in: ‘The Sustainable City III; Urban Regeneration and Sustainability. Wessex Institute of Technology. WIT Press. Southampton. United Kingdom. 2004. Timmeren, A. van, Kristinsson, J., Röling, L.C. The interrelationship of sustainability and resilience- & vulnerability of networks, related to the critical flows in society; a future deadlock?. Proceedings International Conference Sustainable Building (SB05). Tokyo. Japan. 2005. Watts, D.J., Strogatz, S.H., Collective dynamics of small world networks, Nature nr.393. p.440-442. 1998.
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Eco-design of technological systems in buildings L. Marletta, G. Evola & F. Sicurella Department of Industrial Engineering, University of Catania, Italy
Abstract In recent years the use of technological systems in buildings has considerably grown; the components are produced by industrial processes whose energetic and environmental impact is outstanding. The aim of this paper is the evaluation of the environmental impact and the energetic cost related to technological systems (heating, air conditioning, waterworks, fire-proofing, etc.). To this aim the Life Cycle Assessment approach is used; the environmental damage is assessed by means of the Eco-indicator 99 method. For every component (pipes, ducts, wires, radiators) different solutions and materials are considered, corresponding to the current technologies, in order to find out the best and less impactive solution. A case study is then considered to show the environmental benefit achievable by means of a proper design. The technical equipment of a real building is taken into account, and an “ecological” version is defined, by choosing the best solution for every component. The score of the whole apparatus in the ecological version is then compared to the one of the actual installation, showing that an outstanding reduction of the environmental impact can be obtained. Keywords: life cycle, environmental impact, technical equipment, pipes.
1
Introduction
Life Cycle Assessment (LCA) is a well known methodology for the evaluation of the environmental impact associated with the production, use and disposal of a product, taking into account resources and emissions occurring throughout its life, from cradle (extraction of raw materials) to grave (disposal). There is a wide literature concerning the application of LCA to building materials, due to the importance of the sector and to the number of new constructions in previous decades. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060321
320 Eco-Architecture: Harmonisation between Architecture and Nature On the contrary, only recently has this approach been applied to heating and air conditioning systems in buildings; the interest in this field is mostly due to the rapidly increasing number of installations, as opposed to the declining building activity. Some studies can be traced back to the late eighties, concerning the energy use connected with the production of components used in heating systems, such as pipes, radiators and heat generators [1]. These analyses were only focused on the Embodied Energy, whereas no attention was paid to other impacts on the environment. The publication of the ISO standards of the series 14040 [2], [3], [4], [5], which describe and regulate all the phases of an LCA, has led to the development of new complex evaluation methodologies for the assessment of the environmental impact, such as EPS 2000 and Eco-indicator 95, successively updated to the version 99. All of these methods consider a number of impact categories and quantify the environmental impact by means of suitable impact indicators; a final score is then obtained after a process of normalisation and weighting. The publication of these new methods and their consequent implementation in powerful and user-friendly software packages has given new impulse to the LCA analysis of heating and air conditioning systems in buildings. Prek [6] applied Eco-indicator 95 method to compare the use of radiators, fan-coil convectors and floor heating in residential buildings. Nyman and Simonson [7] studied the environmental impact of different ventilation units, with and without energy recovery systems, in order to understand if the further environmental load due to the production of the recovery unit could be overcome by the impact avoided thanks to energy savings. Furthermore, Heikkila [8] applied EPS 2000 to evaluate the environmental impact of a conventional air handling unit, and compared it to a more efficient one, provided with a desiccant rotor to perform dehumidification. In this paper the Eco-indicator 99 has been used to assess the impact associated with the main components of technological systems in buildings, such as pipes, ducts, radiators, gutters, drain pipes. For every component, different options were considered, according to the current practice. The aim is to guide designers to choose the best material for every component, as well as to quantify the advantages connected to the eco-design of technical equipment of buildings.
2
Environmental impact of components: methods
In Table 1 a list is made of the components which have been considered in this analysis. For every component different sizes are actually available, but only one has been chosen, as the results for all the other sizes may be regarded as differing for a simple scale factor. The first step of the analysis was focused on the definition of the functional unit (FU). The standard ISO 14040 defines the functional unit as the quantity of a product system which is able to provide a certain quantified performance; according to this definition, the authors decided to consider a one-meter length as the FU for pipes, wires and ducts, while for the radiator the FU was defined as an WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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element which is able to produce as much thermal power as 150 W when working with a temperature difference of 50°C between water and air. Table 1:
Definition of the components considered in this study.
Component Gutters Drain pipes Sewer Gas distribution Fireproof and sanitary water distribution Hot/cold water for heating and cooling Air ducts Radiators Electric wires r = radius
Dimensions r = 13 cm D = 10 cm D = 15 cm D = ¾”
Functional Unit 1m 1m 1m 1m
D = 2”
1m
D = 1”
1m
D = 500 mm ----S = 2,5 mm2
1m 150 W 1m
D = diameter
S = cross section
Every component may be made up of different materials; all the options normally available in current design and installation practice have been considered. The definition of the amount of material used in the functional unit is derived from information supplied by producers; where no information was available, the weight of the element was computed starting from its size, and adopting the following values for density: PVC : HDPE: STEEL /IRON: COPPER:
1350 kg/m3 970 kg/m3 7800 kg/m3 8900 kg/m3
Some further information should be provided concerning ducts for air distribution. Ducts are not only circular, but they can also have a rectangular shape; in this case, it is possible to define an equivalent diameter, such as the diameter of a circular duct which shows the same pressure losses per meter. If D = 500 mm (see Table 1), the equivalent rectangular section measures 400 mm x 500 mm. Four different types of ducts are normally used (see Table 2). Ducts defined in cases B and C are usually chosen when aesthetic requirements are considered more important than energy savings; case D is also known as flexible duct, as the thin layer of aluminium which forms the main frame of the duct allows the latter to be bendable. As far as electric wires are concerned, the only possible choice refers to the insulating material (PVC or Polyethylene), as copper is in any case used for the core.
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322 Eco-Architecture: Harmonisation between Architecture and Nature Table 2: Case A B C D
Different types of ducts for air distribution.
Shape Rectangular Circular Circular Circular
Material Galvanised Iron Stainless steel Galvanised Iron Aluminium
Insulation Glass wool (25 mm) --------Glass wool (25 mm)
Once all the components have been defined, the Life Cycle Assessment may be performed. To this aim, information provided by European databases have been used for the inventory phase, concerning resources and emissions associated with the production of raw materials, as well as the processes to transform the material into the final product. The LCA has been performed by means of the Eco-indicator 99 method, implemented in the software code SimaPro 6.0. In this study the Hierarchist cultural perspective is adopted, while the weighting is carried out by means of the Average weighting set [9], [10]. Products are considered to be disposed of in landfills at the end of their life.
3
Environmental impact of components: results
In Table 3 and Figure 1 the main results of the analysis are shown. A first consideration can be made about the convenience in using plastic materials, such as PVC and HDPE, for pipes. Thanks to its lightness and to the lower environmental impact of the material itself [10], an HDPE one-inch pipe for heating and cooling water presents a score almost one tenth as high as for copper (0,11 Pt/m vs. 1,27 Pt/m). Copper turns out to be the less environmentally friendly material for pipes, even worse than galvanised iron, which suffers from the process of galvanisation, where zinc is used. However, copper is frequently used in heating and cooling systems because of its good properties, such as resistance to corrosion, low pressure losses and easiness of installation. HDPE is normally adopted for cold water, while it must be properly treated to be used with temperatures higher than 80°C (cross-linked polyethylene). PVC is the most suitable material for gutter, drain pipes and sewer pipes. As far as radiators are concerned, cast iron should be avoided, while steel provides the lowest environmental impact (0,33 Pt per element producing 150 W). Furthermore, the best solution for air distribution is represented by flexible circular ducts; galvanised rectangular ducts are slightly more impactive than circular ones (5,1 Pt/m vs. 4,8 Pt/m), but their score accounts for a layer of glass wool, so their use ensures a reduction of the heat losses which should be considered when making a choice between these two options. Circular stainless steel ducts should be avoided, as their environmental impact is five times higher than galvanised iron ducts (15,6 Pt/m); however, they are often used when no false ceiling are adopted, and aesthetic requirements are more urgent. Finally, the use of PVC or HDPE as insulating material in electric wires is equivalent, as the most relevant contribution is due to the copper core. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Table 3: Component Gutter
Drain pipes
Sewer pipes Pipes for gas distribution Fireproof and water distribution Heating and cooling water Ducts for air distribution
Radiators Electric wires
Main results with reference to the Functional Unit. Materials Copper Galvan. Iron PVC Copper Galvan. Iron PVC Cast Iron PVC HDPE Copper Galvan. Steel HDPE Steel Galvan. Iron PVC HDPE Copper Steel Galvan. Iron HDPE Case A Case B Case C Case D Cast Iron Steel Aluminium Cu + PVC Cu + PE
Weight (kg) 2,99 2,54 0,44 2,23 1,96 0,34 23,6 2,36 2,47 0,86 1,18 0,2 4,49 4,63 1,4 1,05 0,76 2,20 2,28 0,28 17,8* 16 16 2,5 ** 7,1 3,5 1,75 28,5 (g) o 27 (g) oo
* : 16,5 kg steel + 1,3 kg glass wool ** : 1,9 kg aluminium + 0,6 kg glass wool
4
323
Environmental Impact (Pt) 4,83 0,76 0,14 3,71 0,55 0,11 7,24 0,76 0,9 1,43 0,43 0,07 0,74 1,38 0,45 0,38 1,27 0,36 0,68 0,11 5,1 15,6 4,8 2,4 2,4 0,33 1,8 0,0363 0,0360 o oo
Embodied Energy (MJ) 346 137 31,6 267 106 24,4 1830 169 208 103 69 16,8 198 250 100 88 90,6 97,3 123 22,6 927 1550 861 596 595 106 433 2,63 2,59
: 22,3 g copper + 6,2 g PVC : 22,3 g copper + 4,8 g HDPE
Eco-design of technological systems: a case study
In the previous paragraph the most environmentally friendly material was identified for every component related to technical equipment in buildings. In the following a case study is considered to understand how much an eco-design of technical equipment can depart from a conventionally designed system.
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324 Eco-Architecture: Harmonisation between Architecture and Nature Drain pipe (D = 10 mm) 5
4
4
3
3
Pt/m
Pt/m
Gutter (r = 13 mm) 5
2
2
1
1
0
0
Copper
PVC
Galv. Iron
Copper
PVC
Galv. Iron
Sewer (D = 150 mm)
Water / Fireproof (D = 2") 8
1,5
6
Pt/m
Pt/m
1
4
0,5
2
0 Steel
Galv. Iron
PVC
0
HDPE
Cast Iron
PVC
HDPE
Heating Hot water (D = 1")
Gas distribution (D = 3/4") 1,5
1
1
Pt/m
Pt/m
1,5
0,5
0,5
0
0
Copper
Galv. Steel
HDPE
Copper
Ducts (D = 500 mm)
Galv. Iron
HDPE
Radiator (150 W)
16
2,5 2
12
1,5
8
Pt
Pt/m
Steel
1
4 0,5
0 Case A
Case B
Case C
Human Health
Figure 1:
Case D
0 Steel
Ecosystem Quality
Cast Iron
Aluminium
Resources
Eco-indicator 99 scores for the components shown in Table 1.
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Eco-Architecture: Harmonisation between Architecture and Nature
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To this aim the design of a school was taken into account. The school is a one-storey building, which will be built in southern Italy; the ground floor will be used for classrooms and offices, while in the basement the boiler room and some utility rooms will be placed. Each storey surface is 650 m2, and the overall volume is about 6000 m3. The ground floor is provided with a heating system, with an overall thermal load as high as 48 kW, produced by two heat generators (24 kW each). Hot water is delivered to cast iron radiators by means of steel and copper pipes; no cooling or air conditioning system has been designed. In Table 4 the components of the technological systems are listed; the material chosen by the designer is reported, together with the one which should be used according to eco-design principles. Table 4:
Detailed description of the systems adopted in the case study.
System
Heating
Component
Quantity
Radiator
Material DESIGN
ECO
315 *
Cast Iron
Steel
Pipe for hot water distribution
470 m
Copper Steel
HDPE
Heat generator
2
-------
------
Pipe for gas distribution
20 m
Copper
HDPE
Pipe
175 m
Steel
HDPE
Gutter
77 m
Copper
PVC
Drain pipe
146 m
Copper
PVC
Pipe
340 m
HDPE
PVC
Wire
1060 m
Copper and PVC
Copper and PVC
PVC pipe for protection
500 m
PVC
PVC
Fireproof Sanitary water Rain drainage Sewer drainage Electricity distribution * : elements, 150 W each.
Table 5 shows the contribution of each system to the overall environmental impact and embodied energy, as well as the reduction achievable with an ecocompatible choice of the materials. The percentage reduction due to each system is computed as the ratio of the corresponding savings to the overall impact associated with the base-case design. The results are also shown in Figure 3 and Figure 4. The highest impact is shown by the heating system, which is responsible for 38% of the Eco-indicator score and for 46% of the embodied energy. This is mostly due to the use of cast iron radiators, while the impact of the heat generators is not relevant (see Figure 2). The latter has been quantified WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
326 Eco-Architecture: Harmonisation between Architecture and Nature by dismantling a real heat generator and weighting its components and materials, resulting in a score as high as 23,5 Pt and 3150 MJ of embodied energy for each heat generator. Gas distrib. 3%
Heat gener. 4%
Water distrib. 25%
Radiators 68%
Figure 2:
Heating system - percentage distribution of its environmental impact (Base-case design).
The most relevant improvements are given by means of a proper choice of heating and rain drainage systems (31,6% and 32,8%, respectively), i.e. the substitution of copper with PVC and HDPE. Minor improvements are achievable by substituting HDPE sewer pipes with PVC. On the whole, the eco-design of the technological systems may reduce the environmental burden of the 70% if compared to the design solution, which reflects common design practice. Furthermore, the embodied energy decreases down to the 40%. Table 5:
Advantages in performing eco-design of technological systems. Heating Firepr.
Rain drain.
Sewer drain.
Electric
TOT
Base-case design
1112
158
992
606
70
2938
Environm. Impact Eco design (Pt)
184
90
29
509
70
882
Savings
31,6 %
2,3 %
32,8 %
3,3 %
---
70 %
Base-case design
224450
43100
71200
141000
7000
486850
Embodied Energy Eco design (MJ)
47940
20900
6470
114000
7000
196410
36,3 %
4,6 %
13,3 %
5,5 %
---
59,7 %
Savings
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Eco-Architecture: Harmonisation between Architecture and Nature Base-case design
Eco-design
327
% distribution ( Base-case)
1200 Rain drainage 34%
1000
Heating 38%
Pt
800 600 400 Electric 2%
200 0 Heating
Water distrib.
Figure 3:
Sew er drainage
Electric
Rain drainage
Sew er drain. 21%
Water distrib. 5%
Environmental impact: reduction and percentage distribution.
Base-case design
Eco-design
% distribution (Base-case)
250000 Rain drainage 15%
200000
Heating 46%
MJ
150000 100000
Electric 1%
50000 0 Heating
Figure 4:
5
Water distrib.
Sew er drainage
Electric
Rain drainage
Sew er drainage 29%
Water distrib. 9%
Embodied energy: reduction and percentage distribution.
Conclusions
The results presented in this study show how important may be the right choice of the materials, as far as technological systems of a building (heating, drainage, fireproof, etc.) are concerned. Relevant environmental benefits may be derived, as well as a consistent reduction of the embodied energy associated with the production, use and disposal of these kinds of systems. Of course recycling can further reduce the environmental impact; if materials are recycled at the end of their life, according to average European figures on recyclability of plastics and metals, the results shown in Figure 5 are obtained. These results are even more important if we consider that technological systems are either regularly installed in new buildings or periodically renewed in existing buildings, to be adapted to new regulations or to new standards concerning comfort and energy savings. An environmentally aware approach to systems design is therefore of primary importance; the environment can be respected not only by using more efficient systems or cleaner fuels, but also through the attentive choice of materials.
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328 Eco-Architecture: Harmonisation between Architecture and Nature
3000 2500 2000 1500 1000 500
Pt
0
Figure 5:
Base-case design
Base-case design RECICL
Eco-design
Eco-design RECICL
Effect of recycling on the environmental impact (Pt).
References [1] [2] [3] [4] [5] [6] [7] [8] [9] [10]
Baroncini C., Giacchetta G., Lucarini G., Polonara F., Manufacture and running costs for traditional and innovative heating systems, La Termotecnica, 1988. ISO 14040. Environmental management – life cycle assessment – principles and framework. Geneva, Switzerland: International Standard Organization (ISO), 1997. ISO 14041. Environmental management – life cycle assessment – goal and scope definition and inventory analysis. Geneva, Switzerland: International Standard Organization (ISO), 1997. ISO 14042. Environmental management – life cycle assessment – life cycle impact assessment. Geneva, Switzerland: International Standard Organization (ISO), 1997. ISO 14043. Environmental management – life cycle assessment – life cycle interpretation. Geneva, Switzerland: International Standard Organization (ISO), 1997. Prek M., Environmental impact and life cycle assessment of heating and air conditioning systems, a simplified case study, Energy and Buildings 36 (2004), 1021-1027. Nyman M., Simonson C. J., Life cycle assessment of residential ventilation units in a cold climate, Building and Environment 40 (2005), 15-27. Heikkila K., Environmental impact assessment using a weighting method for alternative air-conditioning systems, Building and Environment 39 (2004), 1133-1140. Goedkoop M., Spriensma R. The Eco-indicator 99. A damage oriented method for life cycle assessment. Methodology report. Amersfoort, Netherlands, Prè Consultants, 2001. Marletta L., Evola G., Sicurella F., Environmental impact of materials used in technical equipments: an overview on different methods, Proc. of the 1st Intern. Conference on Eco-Architecture. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
Section 6 Design by passive systems
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331
Sound barriers to enable open windows and integration in landscape G. Rosenhouse Faculty of Civil Engineering - Technion, Haifa, Israel
Abstract Sound barriers are a familiar sight along highways. They act to reduce noise levels in residential areas. As architectural elements that influence the environmental view, sound barriers form a variety of kinds of geometrical shapes, textures, and colour combinations, and they are made of different building materials, such as concrete, plastics (including transparent panels), glass, wood etc. A part of the sound barriers is designed to be impressive, having a strong architectural effect on the landscape. Yet another extreme is possible - merging with the environment. This paper illustrates a diversity of solutions that make part of the environment, and are not significant visually, or at least minimize the intervention in nature. Examples of such designs that are shown here are chosen from a variety that includes the moderate slope barrier, the local screening, the combination of earth berms with walls, lowered roads, hidden walls, walls with end absorption and non planar walls.
1
Introduction
Residential areas near highways, railway lines, airports, industrial premises, recreation areas and other noisy zones are often subject to excessive noise levels, which are beyond the standards limits. Such situations invite acoustic treatment as to reduce the noise levels at noise-sensitive points to acceptable levels. The solutions can be divided into two distinct categories, namely: 1. External screening such as long sound barrier walls along noisy roads. 2. Acoustic isolation of the receiver, such as double glazed acoustic closed windows, or adding air conditioning and acoustic absorption to rooms exposed to noise. In some cases, also combined with acoustic isolation of the source. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060331
332 Eco-Architecture: Harmonisation between Architecture and Nature While the first type may intervene in natural landscape the second one forces people to live in sealed rooms, where direct flow of fresh air is avoided (It should be noted that it is also possible to use ventilation units combined with noise silencers and air cleaning devices, but even then the feeling of open windows is prevented). The need to close windows, which necessitates in turn the use of air conditioning leads also to a significant waste of energy. Yet, the usual low sound barriers (up to 5 m high) cannot screen the upper floors in a high rise building, unless local screening is built over the front of the protected building. A useful observation is that most of the length of highways, for example, passes near rural areas, where typically building height does not exceed two floors. However, in such areas the speed of the cars is very high, which increases the noise level considerably. Planning sound barriers combined with consideration of the topographic conditions can be useful in this case. Regular thin walled sound barriers do not integrate well with local landscapes. For that reason architects of such walls decorate them by using different shapes, materials (including transparent panels) and colours. This solution is not natural, and there exist solutions to the problem. In this paper we show schemes and approaches that integrate environment as it is.
2 Theory A rigid screen that separates between the noise source S and the receiver P and intercepts the sight line SP causes reduction of noise levels at P. The sound barrier can-not entirely avoid the penetration of noise into the “shadow zone” due to diffraction at the edges of the screen, taking into account an approximation of infinite transmission loss through the wall. The most fundamental model of the environmental sound barrier is the rigid, thin half plane (see Figure 1) and several theories have been developed in order to find how much noise reduction is achieved by it. The most popular concept of solving the diffraction pattern caused by the wall is that it combines a superposition of the waves scattered by the edge of the plane and the part of the incident waves that is not blocked by the screen. This idea was first brought into consideration in the 18th century by Young and Fresnel, and had a rigorous mathematical solution for a 2-D problem and a plane wave first introduced by Sommerfeld [1]. During the years, the theory was further developed, generalized, and has obtained integral forms, and applied the use of Wiener-Hopf method. Tolstoy [2] obtained an exact explicit solution for the sound diffracted by a wedge, represented by a sum of infinite series. For a review of other solution methods, see Maekawa [3], Pierce [4], Hu and Wong [5], Menounou et al. [6], Menounou [7], Quis [8], Li and Wong [9], among many others. The simplest solution for noise reduction by a thin half plane that fits the diffraction approximation model of Fresnel-Kirchhoff was presented by Maekawa [3], although this approach was already known (See Redfearn [10]), Rettinger [11–13]), and its fundamental physical model was borrowed from optics (Born and Wolf [14]. Maekawa's Formula reads: WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
Eco-Architecture: Harmonisation between Architecture and Nature
Shadow boundary Br θ = 3π − θs
Region II θs
Shadow boundary Bs
Region I
θ = θs − π
rs
Source
S
333
rr
Region III
θ r Receiver
R
P
θ = 2π θ = 0
screen
S’2 Image source - 2
S’1 Image source - 1 Figure 1:
Geometrical relations between the sources, control point and the half plane sound barrier. 10 lg 10 (3 + 20 N ) for N > −0.05 ∆L p = ; for N < −0.05 0 ∆x = rs + rr − R.
N=
2∆x ; λ
(1)
See glossary in section 5 of this paper and Tatge [15]. Another popular formula is that of Kurze and Anderson [16], which deviates by about 21.5 dBA from Maekawa’s curve for N<1: 2πN ∆L p = 5 + 20 lg 10 tanh 2πN
(
)
for N > 0.
(2)
Also Yamamoto and Takagi [17] formulated four types of more accurate solutions none of which deviates from Maekawa’s formula by more than 0.5 dB. The four solution types are respectively:
WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
334 Eco-Architecture: Harmonisation between Architecture and Nature 10 lg10 [(1 + G ( N) )(N + 0.3)] for N > −0.3 ∆L p = ; 0 for N < −0.3 ∆x = rs + rr − R.
N=
2∆x ; λ
N − 0.005 π G ( N) = 3.621tan + + 6.165{1 − exp[− 0.205(N + 0.3)]} + 2.354. 0.0145 2 (3a) 10 lg 10 N + 13 for N > 1 N 2 ∆x ∆L p = 5 + 8 for − 0.3 < N < 1; N = ; 0.55 + 0.143 N (3b) λ N 0 for N < 0.3 ∆x = rs + rr − R.
10 lg 10 N + 13 for N > 1 0.438 ∆L p = 5 ± 8 N for − 0.3 < N < 1; 0 for N < 0.3
N=
2∆x ; λ
(3c)
∆x = rs + rr − R. 10 lg10 N + 13 for N > 1 0.485 −1 ∆L p = 5 + 9.07674 × sinh N for − 0.3 < N < 1; 0 for N < 0.3
(
)
N=
2 ∆x ; λ
(3d)
∆x = rs + rr − R.
The efficiency of special types of barriers was also investigated. For example, a slit type barrier (Tanioku et al. [18]), a wide barrier following Pierce’s model (Li and Chang-zu [19]), a barrier with a cylinder at the edge (Fujiwara and Furuta [20]) and a barrier with a multiple absorbing edge obstacle (Fujiwara and Ishikuda [21]). If properly designed, sound barriers can reduce roughly 5-15 dB(A) of the noise levels in the “shadow zone”, and this may in many cases suffice to overcome the standards restrictions. Making the top of the barrier absorptive adds about 2 dB(A) to the noise reduction.
3
Sound barriers integration in landscape
3.1 Design approaches There are three main architectural approaches in acoustic screening design for residential areas: One approach makes the barrier a prominent feature in the nearby environment. The second way is to use the building façade for acoustic protection of the interior, including acoustic elements (see Figures 2, 3), and a third one is to design the barrier as a part of the environment, whether natural or man-made (see Figures 4 and 5). All three types can be combined legitimately WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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335
together in the same project. Mostly, the use of sound barriers is protection of residential areas against noise radiated from transportation, industrial premises or sports and recreation areas. In all these cases the aesthetics and view of the barrier is important on both the side of the receiver and the side of the noise source. Residential area
Shadow zone Extension of the lower floor Road
Residential area
Shadow zone Commerce
Road
Shadow zone Residential area Commerce
Road
Figure 2:
An acoustic screening by the building.
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336 Eco-Architecture: Harmonisation between Architecture and Nature
Noise absorbing material over the internal surface of the shielding
Noise screening precast
A fixed window
Shadow zone
A kip window
A fixed window
Boundary of the shadow zone
Noise radiation
Figure 3:
A detail of façade screening.
Shadow zone Hill
Factory
City
Figure 4:
Topographic acoustic shadow.
When the sound barrier is prominent the shaping, materials, colours, transparency, cultural and historical considerations, texture, pattern, caps, maintenance, view and landscaping are points to be considered in the design. In the present paper we emphasize the use of sound barrier that is, as much as possible, non intrusive to the environment. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Figure 4 illustrates a scheme of design where natural topography like a hill creates a shadow zone for a city against the noise of a nearby factory. The artificial counterpart in this case is the earth berm, mound or embankment. The deficiency of the earth berm is its wide base due to its natural slopes, which consume area. This problem can be partially solved by “cutting” the width of the slopes by steep retaining walls. Landscape considerations in sound barrier design are shown in figure 5. A house is located a few tens of meters from a main road as shown in figure 5a. Being exposed to heavy transportation noise, the measured levels are too high, which invites the design of a shadow zone by screening. The amount of needed noise reduction follows standard noise limits. The next step is calculation of the barrier height by using for example one of the aforementioned formulae. One of the possible solutions is road depression, which may solve the problem, but causes a steep cut in the landscape (see figure 5b). This cut should be very long since otherwise the screening will not be effective. Another possibility is shown in figure 5c. A thin sound barrier is built, which may have the same effect as the cut. This wall has to be also very long, or, alternatively perpendicular walls should be added along the border of the area that belongs to the house. Because of this screening, some activities can be done beyond the wall, due to its noise reduction. A combination of road depression and a thin wall barrier yields more acoustic shadow as shown in figure 5d. A road depression combined with a horizontal slab (see figure 5e) yields an effect that is similar to that of the scheme in figure 5d. Finally, a solution that integrates better with the environment and is not less effective can be obtained if the house is distant enough from the road. A small slope angle created in the area in front of the house and right landscaping gives us the advantage of road depression and thin walls noise protection. It should be noted that due to the ground sound absorption, about 2-3 dB can be added to the noise reduction as compared with non-absorptive sound barriers of the same height.
4
Conclusion
Designing against noises of road and railway traffic, factories, and recreation and sports areas can be done by using sound barriers. The theoretical analysis of noise reduction by such shielding is now established, backed by a huge amount of experimental data and evidence. At this stage researchers are trying to blend active noise control in design of barriers, but this a future trend. As a consequence of the intensive development in this area, the resulting engineering tool allows for architectural and environmental considerations without any analytical burden. The present paper illustrates how by involving architecture, the design of noise protection of residential areas can be friendly to the environment and landscaping. The additional benefit of the suggested approach is that a proper design may allow for building houses in a noisy area, still enabling living with open windows. This means allowing natural fresh air into the room through the windows, and saving artificial ventilation and air conditioning energy. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
338 Eco-Architecture: Harmonisation between Architecture and Nature No shadow zone but some trees of low acoustical influence
a House
Road
Shadow zone
b House
Road depression
Road
Shadow zone Sound barrier
c
park
House
Road
Shadow zone
Road depression combined with a sound barrier
d House
park
Road Shadow zone
e park
House Shadow zone
f
Road
Intentional slope
House
Figure 5:
5
Road depression combined with an horizontal roofing
Road
Landscape acoustic screening.
Glossary
N – Fresnel number. P – control point. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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R – the length of the sight line, SP, m. rs – the distance between the source and the top of the barrier, 2-D analysis, m. rs – the distance between the control point and the top of the barrier in 2-D analysis, m. S – sound source point. λ – source sound wave length, m. ∆Lp – reduction of sound level by the screen, at the control point, dBA.
References [1]
Sommerfeld, A., Mathematische Theorie der Diffraction. Math. Ann. 47, 1896. [2] Tolstoy, I., Exact explicit solutions for diffraction by hard sound barriers and seamount. Jr. Acoust. Soc. Am., 85, pp. 661-669, 1989. [3] Maekawa, Z-I, Noise reduction by screens. J. Appl. Acoust., 1, pp. 157173, 1968. [4] Pierce, A.D., Diffraction of sound around corners and over wide barriers. Jr. Acoust. Soc. Am., 55(5), pp. 941-955, 1974. [5] Hu, Z. & Wong, R.L.M., Barrier insertion loss versus Fresnel number and secondary parameters. Noise Con. Engineering J. 20(1), pp. 31-36, 1983. [6] Menounou, P., Bush-Vishniac, I.J. & Blackstock, D., Directive line source model for sound diffracted by half planes and wedges. J. Acoust. Soc. Am., 107, pp. 2973-2986, 2000. [7] Menounou, P., A correction to Maekawa’s curve for the insertion loss behind barriers. Noise-Con 2000, ed. J.J. Van Houten, Newport Beach California, CD, 2000. [8] Quis, D., Diffraction by half-plane: useful approximation to an exact formulation. J. sound Vib., 252, pp. 191-221, 2002. [9] Li, K.M. & Wong, H.Y., A review of commonly used analytical and empirical formulae for predicting sound diffracted by a thin screen. J.Appl. Acoust., 66 ,pp. 45-76, 2005. [10] Redfearn, S.W., Some acoustical source-observer problems. Phil. Mag. 30, p. 223, 1940. [11] Rettinger, M., Noise level reduction of barriers. Noise Control, 3(5), pp. 50-52, 1957. [12] Rettinger, M., Noise level reduction of “depressed” freeways. Noise Control, 5(4), pp. 212-254, 1959. [13] Rettinger, M., Acoustic Design and Noise Control. Vol. 2: Noise Control. Chemical Publishing, NY, pp.315-324, 1977. [14] Born, M. & Wolf, E., Principles of Optics, 4th ed. Pergamon Press, pp. 375-386, 1970. [15] Tatge, R.B., Bar-wall attenuation with a finite sized source. J. Acoust. Soc. Am. 53, pp.1317-1319, 1973. [16] Kurze, U.J. & Anderson G.S., Sound attenuation by barriers. J. Appl. Acoust. 4, pp. 35-53, 1971.
WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
340 Eco-Architecture: Harmonisation between Architecture and Nature [17] [18]
[19] [20] [21]
Yamamoto, K. & Takagi, K. Expression of Maekawa’s chart for computation. J. Appl. Acoust. 37, pp.75-82, 1992. Tanioku, Y., Konishi, K. & Maekawa, Z-I, Noise reduction of a slit-type barrier by using the line integral method and full scale model measurement. Inter-Noise 87, ed. Li Pei-zi, Beijing, China, Pp. 395-398, 1987. Li, Z. & Chang-zu, Z., Diffraction field of traffic noise behind building along a street. Inter-Noise 87, ed. Li Pei-zi, Beijing, China, Pp. 403-406, 1987. Fujiwara, K. & Furuta, N., Sound shielding efficiency of a barrier with a cylinder at the edge. Noise Con. Engng J. Beijing, China, pp. 5-11, 1991. Fujiwara, K. & Ishiduka, T., Noise Shielding efficiency of a barrier with multiple absorbing edge obstacle. Inter-Noise 99, eds. J. Cuschieri, S., S. Glegg & Y. Yong, Fort Lauderdale, Florida, pp. 451-454, 1999.
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Practicing what we preach M. Lawton Landcare Research, New Zealand
Abstract In 2001 Landcare Research embarked on a journey into the unknown – the design and development of premises for 100 of our staff in Auckland. Sustainability is the central thread of Landcare Research’s core business but we also try to practise what we preach, so when we came to build new accommodation, we knew we had to be innovative and to some extent courageous in breaking new ground. We set and achieved high environmental and sustainable design objectives for the building, based on our ethos as an organisation that champions sustainable development through lowering resource use and dramatically reducing waste. We agreed that the building had to be designed for sustainability. Construction costs were not to be increased because the building was sustainable. Projected energy operating costs should be about 60–70% less than for a conventional building. The building would make minimal use of municipal water, stormwater and sewage systems. In addition, we wanted the building to be a great place to work and to reflect our Pacific culture and specific Auckland location. We continue to adhere to those principles in our ongoing management of the building, and monitor and manage it as a research and demonstration site for low-impact urban design. This presentation will outline the drivers of sustainability in New Zealand and how they were translated into the goals we set ourselves for our sustainable building. It will also focus on the problems that face design professionals and their clients when they choose developments that are not mainstream, and present suggestions to overcome them. Keywords: sustainable architecture, energy efficiency, water management.
1
Introduction
It is now well accepted that the world has a limited source of natural resources and a limited ability to deal with waste. That’s a given, a fundamental law of WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060341
342 Eco-Architecture: Harmonisation between Architecture and Nature nature. Our global footprint, the amount of resource used globally, already exceeds by a third a level that can be defined as sustainable, that is will allow for the needs of future generations [1]. In addition, the footprint varies widely between countries emphasising global inequities. In New Zealand we have not yet exceeded our footprint but that is only because we have a magnificent landscape and small population. It is possible that previous post-industrial generations could be forgiven such extravagance; they simply did not have the data, even if they may have sensed that all was not well. The present occupants of this planet do not have that excuse. Despite the fact that science has still much to learn about how the world works, how species evolve, how climate cycles are influenced and what feedback mechanisms exist, the pattern of Western living will need to be changed, sooner or later, to adjust to global environmental concerns. The increasing development of China and India will only accelerate a global environmental crisis already on the horizon. So that is the big picture, a huge political, technical, social and economic web to disentangle so that we can find the balance that allows for global societal wellbeing in a sustainable way. All countries will face the same pressures, some more than others, but New Zealand with all its inherent natural wealth should be leading the way, a natural design laboratory for the world. What are the key urban development issues in New Zealand? The main consideration has been the provision of future energy sources, but the need to upgrade stormwater and sewage disposal systems is also of concern. Discussion usually seems to focus on the need to replace and rebuild, to find new sources, and to ensure above all else that we maintain our current high standard of living. Implicit in that way of thinking is that our behaviour need not be required to change, that we should be able to keep on using power whenever we want and should not have to think about how we get rid of any waste other then a modest attempt to recycle our newspapers, wine bottles and some plastic domestic solid waste. We know we could be less resource consumptive and produce less waste but that requires a change in behaviour, not an impossible task but something that could be facilitated by good leadership and a political and economic framework that encourages sustainable development. It is easy to say that people are the problem but behaviour would be strongly influenced by a more innovative approach from town planners, architects, engineers, local body politicians and industry. Much easier to be “green” in a house that does not need much energy or in a society that does not buy produce in excess wrapping or that lives in houses with toilet waste systems that do not require large amounts of water to flush away the contents. In the case of energy, a substantial reduction in energy demand, along with the development of a wider range of renewable energy sources, would diminish New Zealand’s issue of looming power failures and the need to enhance energy generation from fossil fuels. We should maintain a national grid by all means, but have that grid supplemented by local grids supplied through individual buildings that contribute or draw from the system as required. Let the grid act as a battery but have as much energy as possible generated where it will be used. Then design houses and develop precincts that minimise the need for energy WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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through orientation, aspect and material selection, and New Zealand, with its modest population growth predictions, would have no trouble in achieving its power needs without compromising productivity and comfort. Stormwater is a major problem wherever there are modest to major communities. The problem is two fold: the disruption of the hydrologic cycle by concentrating stormwater in pipes, leading to flash floods; and the contaminants, carried by the stormwater, mainly from road transport, which end up in our streams and harbours. Impervious surfaces add to both problems. The percentage of many urban impervious surfaces has increased in the last few years through in-fill housing, much smaller sections and larger houses and large tar-sealed driveways. No wonder the Auckland stormwater system is in trouble. There is insufficient natural filtration of water through the soil both to moderate its flow and absorb contaminants. Toilets, not a subject that most people want to spend time thinking about, certainly not discuss at dinner parties, are unpleasant but necessary evils, which help take our waste away so that we do not have to think about it. Their design has improved in latter years so that they have low water-use alternatives. In general, however, the principle has not changed and most still use large amounts of water directly from the municipal supply. The logic of cleaning water to potable standards and then flushing it down the toilet evades me. With massive redevelopment projects in Auckland getting underway, there is huge potential for further environmental degradation. However, if low-impact urban design and development practices become mainstream, enormous environmental improvements could be expected – with social and economic benefits ensuing. In any building, whether small domestic to large commercial, there are numerous improvements that could be made to limit resource use and waste production. The problem is that very few people are taking that opportunity despite the obvious advantages. Our experience in low-impact urban design in our recent building project has uncovered a number of reasons for this: • The prospective owners do not understand the problem or what can be achieved. • There are too few professionals in the design industry with a background in ecological engineering and sustainable architecture. • Anything can be built if the price is right, so there is a perception and sometimes a reality that eco-buildings are more expensive than conventional buildings. • While the design industry has some understanding of the problem, the construction industry, construction contractors and material suppliers have very little.In general developers have not been interested in moderating development to address environmental concerns. There are some exceptions. • Building code and compliance standards can work against innovation. Often people work to the minimum standards, when going above them would be beneficial.
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Risk is a major factor in that anything new may be risky and may not be suggested by the design team or the construction company, because of liability issues. Environmental, economic and social data need to be put in a form that is able to influence plans, codes and practice.
2 The Landcare Research building Despite the above constraints and in part in blissful ignorance of the potential pitfalls, Landcare Research when it came to consider a new building for staff in Auckland, decided they wanted as sustainable building, at the forefront of ecodesign in New Zealand. Clearly they wanted a sound functional building, suitable for all the various activities staff carry out. They wanted a good place to work and agreed with the University of Auckland to co-locate onto the Tamaki Campus to facilitate collaborations with University staff. The main functions of the building provided a challenge being: • House our national insect collections of 6.5 million insects, one million of them mounted with pins, in a state-of-the-art collection facility. • Likewise for our national fungal collection of 600 000 specimens. • Provide for containment facilities within our laboratories to meet PC2 standards. • Provide containment and propagation glasshouses. • Ensure the building could be monitored as part of our ongoing urban research. • Provide space for 60 Landcare Research staff, 25 MAF staff, and a number of University collaborators. As an organisation we also had some key goals relating to sustainability: • The building had to be designed for sustainability. • Construction costs were not to be increased because the building was sustainable. • Projected energy operating costs should be about 60–70% less than for a conventional building. • The building would make minimal use of municipal water, stormwater and sewage systems. We assembled a design team with some experience in sustainable buildings and were fortunate to be able to include Robert Vale from the University of Auckland to assist. We went through many of the usual processes of seeking staff consultation through workshops and scoping our requirements. We had some of our own ideas of what a sustainable building should incorporate and we threw them into the mix. The design and build process took 18 months and no doubt there would have been some improvements if there had been more time to explore a wide range of options. We moved into the building at Easter and have been settling in for the last 2 months. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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2.1 Building features Pressure did come on the cost-plan, and the original size of the building was scaled back. Nevertheless, we are very pleased with what we have achieved through the ideas of the architects, Chow-Hill, the innovations of Connell Mott MacDonald, the forbearance of Hawkins Construction, and our own perseverance in the face of some adversity. The key features that have added to the sustainability aspects of the building are dealt with below. 2.1.1 Energy The goal was to maximise passive climate control in keeping the warmth in but excess heat or cold out so that pleasant working conditions were maintained throughout the buildings irrespective of the weather outside. Inside temperatures are expected to range from 17 to 25oC for offices and laboratories (winter/summer) when external temperatures will be between 6 and 27oC. We deliberately did not aim for a smaller temperature range that would have required more active climate control and intervention. The energy consumption target is 100 kW hrs/m2/yr averaged over offices, collection spaces and laboratories, the latter being notoriously energy intensive. A conventional office building would consume approximately 200 kW hrs/m2/yr, and a building with laboratories would use closer to 300 kw hrs/m2/yr. Limiting energy consumption will be achieved through design features that reduce the need for heating and cooling (minimising direct energy consumption), and by recovering and reusing waste heat. In addition to our environmental saving, good energy management will save us up to $70000 a year. Some of the design features to help achieve that include: 2.1.1.1 Building materials The external shell of the building is multi-layered to limit heat gains from or losses to the outside. The innermost layer is a concrete block wall (keeping the thermal mass on the inside), then a thick layer of rigid fibreglass insulation, a ventilated cavity, a vapour seal layer, and finally timber or metal cladding on the outside. Internally, exposed concrete has been used extensively to increase the thermal storage capacity of the building. During the initial decision-making design stages, innovative energy modelling software was used to optimise placement of windows and window shades and the building fabric options. The software assessed natural lighting, heating and ventilation for various times of the day, every day of the year. 2.1.1.2 Insulated walls and roof Expenditure and performance has been focussed on areas where it is needed most: • •
High-performance insulation has been used for the roof, walls and floors of the Biological Collections Mid-level insulation (R4 fibreglass batts, which is several times the recommended amount) has been used in the atrium and office façades.
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Low-level insulation has been used internally between air-conditioned and non-air-conditioned areas. (A typical office loses 28–30 W of heat per m2 of un-insulated wall. With insulated walls this drops to 8 W.) 2.1.1.3 Windows Windows are double-glazed, with opening frames for fresh air. Windows will need to be closed at night and during temperature extremes to help maintain the reasonably constant inside temperatures. (A typical office loses 100 W of heat per 1 m2 window. With double-glazing, this drops to 56 W.) 2.1.1.4 Heat recovery ECO-AIR units that incorporate heat exchangers recover waste from the refrigerator/freezer systems, the air-conditioning/dehumidifying systems, and some of the fume cupboards. The building has 11 fume cupboards, and the energy associated with their operation (including replacing the air they suck out) is the greatest single energy use for the whole building. The refrigeration system serving the freezers and Collections space dehumidification system both contribute to a skirting radiator system throughout the offices. A gas-fired booster system has been installed to supplement, if needed, the recovered heat and solar heating systems. 2.1.1.5 Solar panels Two solar panels on the roof provide the energy needed for the hot water usage throughout the laboratory systems. The cafeteria has a separate solar hot water storage system that is independent of the laboratory systems. 2.1.1.6 Wind-powered generator A small (400 W) wind-powered generator by the glasshouses provides sufficient power to pump rainwater from the storage tanks (by the glasshouses) back up to the roof tanks that supply water for flushing urinals and ground floor toilets. Wind is a ‘sustainable’ form of energy, and incorporating a windmill generator contributes to the overall sustainability of the stormwater management on site and further reduces energy consumption from the national grid. 2.1.2 Sewage The goal was to minimise the load that 90 staff, visitors and laboratory usage places on the sewer and wastewater system. The key to achieving this goal was using low-impact alternatives that meet all health and waste discharge requirements. 2.1.2.1 Composting toilets Using waste materials as a resource is a fundamental of nature or ecological systems. Human waste, once composted, is a rich source of carbon and nitrogen that can be added to soil to enrich its productive and filtering capacity. Composting toilets are frequently considered for use in rural areas as an alternative to septic tanks. There is no reason, however, why they cannot be WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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considered in a built-up area. There may be some occasions when they are simply not practical but there will be many times when they are. Putting composting toilets in our urban commercial building has been one of the more controversial aspects of the building and, it must be admitted, this feature still has its sceptics amongst the building occupants. The first and second floors in our building have composting toilets with seven toilets feeding two large Clivus Multrum units. These toilets are located against the North wall to help keep the composting tanks warm for optimal functioning. Cleaning requires bio-friendly products similar to those used with a septic tank system. It is expected the tanks will need emptying about once every 6 months, and the tank area has external access to make servicing easier. The system conforms to the Australian standard for composting toilets, and the New Zealand standard for on-site wastewater disposal. This means compost can go onto the surrounding gardens. Liquid toilet waste drains to the sewer system, as do the urinals and washbasin wastewater. Wastewater from laboratories goes via local sediment/dilution traps to the sewer via a 1000-litre detention/dilution tank, and then into the sewer system. There is insufficient land area available for soakage pits for ‘grey water’ disposal. 2.1.2.2 Ground-floor conventional toilets For the ground floor, low water-use flush toilets have been installed. Rainwater (collected and stored on site) is used for flushing these toilets plus the urinals on all floors. Composting toilets were not suitable for the ground floor because the hole that would have needed to be excavated for the collection unit of the composting toilets would have been below flood level. This, plus the additional costs associated with excavation, extra pumping, tanking and ventilation, made ground-floor composting toilets impracticable and uneconomic. Overall, we have achieved our goal by ensuring that the load being placed on the sewer system is markedly smaller than for a conventional building of similar size and function. 2.1.3 Water and wastewater management The goal was to reduce both the amount of water purchased from Auckland Metro and the amount of water entering the stormwater system. By harvesting rainwater and using it on site, we are reducing the need for mains water and the infrastructure needed to supply it and remove stormwater. 2.1.3.1 Rainwater harvesting Instead of rainwater running into the stormwater system, as much as possible is collected and stored on site for use in all urinals (manual flushing), ground floor toilets, and for irrigating gardens and glasshouses. Rainwater harvesting for water reuse is an obvious way of limiting the demand on future water supplies but currently it is only applied in rural areas. It is one relatively simple change that could be made to a significant percentage of our urban infrastructure.
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348 Eco-Architecture: Harmonisation between Architecture and Nature Water running off all the roofing areas is gravity fed to a 25 000-litre tank near the glasshouses. Water is pumped from the main storage tank back up to the roof header tank using electricity supplied by a small wind turbine. Two additional 25 000-litre tanks detain stormwater overflow from the main tank. Overflow from the detention system (e.g., during a big storm when the tanks are already mostly full) will overflow into the rain garden (still to be constructed). A soak pit, which penetrates the basalt rock layer, allows approx 10 l/sec to drain way. Any excess over this will still enter the municipal stormwater system through the normal curbing channels and drains but the volumes will be drastically reduced compared with situations where collection and detention systems are lacking. The cost of the tanks and wind turbine generator was offset by not needing to run downpipes to the ground and connect them to underground stormwater systems, and by savings in Auckland’s Metro water charges. Mains water is used for basins and for drinking. Although hand basins use mains water they have low-volume water-saving taps to prevent unnecessary wastage of water, including the hot water heated by solar panels. 2.1.3.2 Purified water for laboratories Reverse osmosis or hyper-filtration is the finest filtration known, and is used to provide pure water to the laboratories with specialist requirements for slide preparation and uncontaminated glassware. A reverse osmosis machine is a large consumer of water as only a small proportion of the water (maximum 30%) flowing through the machine actually passes through the filter. The system has been configured so that the reject water can be collected for re-use in urinals and for garden irrigation, i.e. the reject water is incorporated in our stormwater management system. We have the option of using either rainwater off the roof or mains water in the reverse osmosis machine. However, using recovered rainwater may extend the life of the reverse osmosis resin filter because the rainwater probably has less dissolved salts than tap water. 2.1.3.3 Runoff from the car park and roads The car park has been constructed with a pervious gravel surface that allows rainwater to infiltrate the surface. During storms, excess water beyond what the soil can normally retain, will flow through the soil down the gentle gradient to an area to be shortly developed as a rain garden. This involves collection into a stormwater pipe to take the water under the building foyer to the front of the building where it will be released into soil and a wetland area. Any excess water will flow through the soil into the stormwater network. The overall water volume will have been significantly reduced and contaminants filtered out. 2.1.4 Other features As limiting resource use was a key goal, we limited the inclusion of excess materials where possible. There are many areas with no false ceiling but exposed ceiling trays carrying pipes and wiring below the concrete upper floors or roof. Most of the office and corridor floors are concrete, which acts as a heat sink. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Carpets used in meeting rooms and admin offices are tiles from Interface Carpets. They are off-cuts that form an interesting pattern. Once they are ready to be replaced they will be extensively recycled. Laboratory coverings are a product called Marmoleum. It looks like vinyl but is made from jute and natural resins and can be composted after its 25-year lifetime. Organic solvents in paints and varnishes were minimised. Light fittings are low energy usage.
3
Where to from here?
The building has already fulfilled its purpose in a number of ways but the hope is that it will continue to be an example of some or all of the features others may wish to consider when they come to build. We will incorporate the monitoring and management of the building into our mainstream urban research, continue to make public its performance, and suggest further improvements. Some of the deterrents for the widespread uptake of ecological features were mentioned earlier. These are not insignificant. Some of the things to consider when going down the sustainable building path must include: • Having a design team that is really committed to the goal and has in it some experience in sustainable design. • Remembering that sustainable design does not have to stand out like a sore thumb, especially if that adds to the costs. • Client and design team being prepared at this stage to take some, at least perceived, risk, in moving away from the status quo. • Having end-users who are prepared to accept a building they may need to manage actively, to open and close windows, and to adopt a wider climate comfort range than normal. • Choosing a framework for decision making – there are several available – and spending the time required to consider the trade-offs in terms of sustainable features, e.g., the various aspects of embodied energy in choosing materials in relation to the life-cycle of the building. In the longer term there needs to be more fundamental changes to the Construction Industry: • Major suppliers of materials should be aiming to procure only certified sustainable products. There needs to be better traceability so that customers know where the materials come from. • More robust and accepted financial systems should take account of the reduced operating costs of a sustainable building and, as is often the case, the longer building lifetime when considering depreciation. • There will either need to be a move away from working to the minimal building code and compliance standards, or those standards will need to change to encourage more sustainable behaviour. • We had anticipated more concern from our local Council than we encountered. We were pleasantly surprised. However, for sustainable development and design to become mainstream councils need actively WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
350 Eco-Architecture: Harmonisation between Architecture and Nature to promote such an approach through a range of mechanisms, and they also need to coordinate between their planning and consent departments to give a consistent message. There was more time and effort involved in achieving our building than we had anticipated/planned for but it was a rewarding process, well worth the effort. We hope it can encourage others and, through some of the learning involved, make it easier for them to follow suit.
Reference [1] Loh, J., Living Planet Report 2002, Gland Switzerland: WWW-World Fund for Nature.
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Guidelines for sizing roof windows S. Robertson & M. Thompson University of East London and the Centre for Alternative Technology, UK
Abstract Roof windows are often used as a major glazing element in loft conversion projects and to create a room in the roof space of new residential developments. Selecting the correct size of roof window is subject to a range of potentially competing influences, including the need to satisfy building regulations and planning control legislation. This paper describes a recent investigative project to address a particular research question: ‘When considering the daylighting and energy consumption aspects, how can designers determine the appropriate size and position for roof windows in loft rooms?’ The primary objective was to identify appropriate roof window size and position for a typical loft room, when based on accepted numerical daylighting criteria. The research method that was adopted used standard calculations, scale modelling under an artificial sky, computer simulations and internal illuminance measurements for real loft rooms. The relative daylighting performance of a dormer window was also determined using similar techniques. By considering an example of typical modern residential construction, it was then possible to illustrate the effect of variation in roof window size on annual energy consumption. Finally, the paper outlines the preliminary development of a simple graphical design tool that exploits the research. This tool is intended to assist homeowners and designers in selecting roof windows that optimise both the daylighting and energy consumption aspects. Keywords: roof windows, dormer windows, loft conversions, daylighting, energy consumption, design tools.
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Introduction
Roof windows are tilting double glazed units that are fitted in the plane of the sloping roof surface. Such windows are often used as a major glazing element in conversion projects for domestic lofts, agricultural barns and former industrial WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060351
352 Eco-Architecture: Harmonisation between Architecture and Nature buildings. Modern construction techniques including structural insulated roof panels and planning trends such as the higher density requirements for new residential developments mean that roof windows are also increasingly used to illuminate rooms within the roof space of new build housing. Selecting the appropriate size for roof windows is subject to a range of potentially competing influences, including the need to satisfy building regulations and planning control legislation. For instance, the understandable desire for a well daylit interior with consequently low electric lighting load may well conflict with the need to achieve a low average U value and the associated reduction in the annual heating energy requirement. In relation to the sizing and position of conventional vertical windows, the question of daylighting has been investigated and documented by authors such as Hopkinson et al. [1] and Littlefair [2]. Much of this work on daylighting theory has been embodied in practical guides including the CIBSE Lighting Guide LG10 Daylighting and Window Design [3]. Baker and Steemers [4] have produced material that describes the potential conflict between daylighting and thermal performance requirements and have developed this to provide predictive techniques such as the LT Method. However, there is little independently published work to provide the same degree of guidance for sizing roof windows. Whilst it is possible to determine optimum roof window size using some of the sophisticated lighting and thermal simulation tools that are now available to designers, this level of effort is unlikely to be appropriate for a typical loft conversion or new build project. Consequently, for mainstream construction projects it is common practice to refer to the available industry guidance from industry bodies and manufacturers in order to identify design solutions. As far as the leading manufacturer of such windows is concerned, the available guidance on the topic of roof window sizing has historically used a comparatively simple rule of thumb approach [5]. This proposes a minimum glazed area equivalent to 10% of the floor area in order to achieve adequate natural daylighting levels. It is further suggested that the overall effect is usually improved by increasing this ratio to around 20% of the floor area. An associated common statement is that a roof window will admit 40% more light than the equivalent dormer window. This guidance also appears in a number of texts that are aimed at homeowners who may be considering a loft conversion project [6]. Choosing the correct size of roof window is important both for external aesthetic and building performance reasons. Although normally prevented by compliance with Building Regulations limits, extreme instances of incorrect sizing could actually produce loft rooms that are unusable. This might be due either to the creation of a poorly illuminated, stuffy attic or a loft room with such a large area of glazing that it resembles a solar oven in summer and a cold garret in the winter. Selecting the optimum size of roof window can undoubtedly produce light, airy loft rooms so the objective of the research was to increase the frequency of this situation for future design projects. Estimates of the total number of such roof windows that are being installed each year were derived from sources such as manufacturer revenue data [7] and the English House WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Condition Survey [8]. It appears that there are approximately 450,000 roof windows being installed in the UK each year, so any general trend towards inappropriate sizing can reasonably be multiplied by this value to determine the cumulative effect. Therefore the aim of the research was to answer the question: ‘When considering the daylighting and energy consumption aspects, how can designers determine the appropriate size and position for roof windows in loft rooms?’
2
Objectives
The primary objective was to identify appropriate roof window size and position for a typical loft room, when based on accepted numerical daylighting criteria. Average daylight factor (ADF) is defined as the ratio of average indoor to outdoor illuminance and is the most commonly used indicator of daylighting within a nominated room. The current British Standard BS8206 [9] specifies required daylighting levels based on ADF values of between 1% and 2.5% subject to the intended use of the room in question. However, it is generally accepted that most people now prefer daylighting levels that are approximately twice those defined in this standard [10]. Therefore, this study considered daylighting levels in the range 2% to 5%, with an optimum value of 3.5% at the centre of this ideal range. The particular case of a loft room was selected since it represents one of the most frequent situations in which such windows are used. It also provided a common test case to which a number of different assessment techniques could be applied. The loft room dimensions that were used were consistent with those published in the guidance notes from the leading manufacturer of roof windows [11]. A physical 1:10 scale room was constructed for comparative investigation and a standard CAD toolset was used to create a software representation of the same loft room. In addition, these dimensions matched those of an available full size loft room. It was therefore possible to use a number of different research tactics to determine these indicators and compare them with real world data. Numerical results and observations associated with these different approaches are considered in the following section.
3
Research
3.1 Calculation A proposed calculation method for ADF is described by Littlefair [2] and cited in LG10 [3]. This is a widely accepted single stage technique that is used to calculate ADF from a number of fixed variables. Although this approach is more usually applied to vertical windows, LG10 does show it being applied to sloping glazing and in the absence of any other readily available single stage technique, this method has been used to assess its suitability for sizing roof windows during the loft room design process. This is found using the Littlefair and Plymouth expression: WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
354 Eco-Architecture: Harmonisation between Architecture and Nature ADF = TAw∂/A(1-R2)% where the terms have the following meanings: T Aw ∂ A R
diffuse transmittance of the glazing net area of the window angle of the visible sky in degrees total area of the room surfaces average internal surface reflectance
Based on these calculations, it seems that the predicted ADF for the typical loft room will be approximately x0.35 the ratio of glazing to floor area. This implies that a roof window of 10% of the floor area would result in an ADF of 3.5%, which is in the centre of the ideal range. 3.2 Scale modelling Next, a scale room placed under an artificial sky was used to determine the ADF for a number of test cases. The 1:10 scale room had dimensions equivalent to 4.0m x 2.5m internal floor plan and 2.5m internal ceiling height with a 45o pitch. The internal finishes of the scale room were generally identical with those of the full size room and the external surfaces of the scale room were finished in black to represent a typical concrete tile or slate roof surface. As is normal practice for such scale rooms, no glazing was installed and a correction factor was then applied in the analysis. This scale room was placed under an artificial sky, of the mirror box type that replicated overcast sky conditions. Internal illuminance levels were measured using a 0.5m scale grid on a working plane at 0.7m scale height. The results suggested that with a 2.0m head height and a typical room profile, installation of a roof window will result in an average daylight factor (ADF) that is 0.46 x the glazing to floor area ratio. Therefore in a typical loft conversion with a 45o roof pitch, from the scale modeling it appears that an average daylight factor (ADF) of 3.5% can be achieved using a roof window with a glazing to floor area ratio of 7.6%. 3.3 Simulation Daylighting simulation tools such as Radiance [12] and FlucsDL [13] can be used to predict daylighting levels and numerical indicators such as ADF. The simulation model was a single loft room with dimensions of 4.0m x 2.5m internal floor plan, 2.5m internal ceiling height and a 2.0m window head height. All the detailed dimensions of the room were consistent with those of the scale room and with those of the full size loft room. In setting up the simulation, the location and orientation together with all of the internal finishes, glazing type and construction materials were either the default values used within the Radiance and FlucsDL simulation environments or were set to be consistent with those of the scale room. In order to be consistent with the data from the calculation and scale modelling, this daylighting data also used simulated WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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overcast sky conditions. The Radiance simulation work suggested that installation of a roof window would result in an ADF that is 0.43 times the ratio of glazing to floor area. Within a reasonable margin of simulation error, the work with FlucsDL generally supported these findings and showed that a roof window will result in an ADF that is 0.45 times the ratio of glazing to floor area. Therefore, in a typical loft room with a 45o roof pitch, the simulation work predicted that an ADF of 3.5% could be achieved using a roof window with a ratio of glazing to floor area of between 8.13% (Radiance) and 7.78% (FlucsDL). 3.4 Measurement Comparing these results with measured data from a full size loft room was also possible since all the dimensions and internal finishes were consistent. This loft room also had plan dimensions of 4.0m x 2.5m and a 45o roof pitch. In this room, the roof window had a glazed area of 0.82m2 with a head height of 2.0m. Data was collected for the equivalent grid points as used in the scale room. Based on three sets of data collected, the measured ADF was found to be 4.97%. Applying these findings would imply that in order to achieve an ADF of 3.5% with a fixed head height of 2.0m, it would be necessary to install a roof window with a glazing area of 5.83% of the floor area. 3.5 Summary For the typical loft room that was investigated, the combined calculation, experimental, simulation and measurement data in this study seem to suggest rather lower values for the required glazing area than that which has been identified in the majority of the existing guidance material. The findings are: • • • • •
Method Calculation Scale modelling Simulation Measurement
ADF:glazing to floor area ratio 0.35:1 0.46:1 0.43:1 to 0.45:1 0.60:1
Averaging these findings and applying equal weighting to each, it appears that a linear relationship of ADF to glazing to floor area ratio of 0.46:1 will generally apply. This means that in a typical loft room, a roof window with a glazing area of 7.6% of the floor area will normally result in an ADF in the region of 3.5%. If the two extreme values based on the calculation and measurement aspects are ignored then an almost identical linear relationship will still apply. This second approach may be justified on the basis of the potential inapplicability of the Littlefair and Plymouth expression to roof windows and the reduced confidence level for the measurement data due to the inevitably limited number of data points associated with one full size loft room.
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356 Eco-Architecture: Harmonisation between Architecture and Nature 3.6 Comparison with dormer windows In visually sensitive situations for historic buildings and conservation areas, it is possible to debate the relative merits of dormer windows as compared with the use of small conservation rooflights. To a degree, any conclusions on this topic are somewhat subjective. However, the internal room qualities can be assessed more objectively. A comparative investigation using the well proven Radiance daylighting simulator has previously been published by Dubois et al. [14]. It indicated a relative ADF for a roof window of approximately 3 times that of a dormer window of equal glazed area, which seems to be at odds with the published guidance from a major roof window manufacturer. The work carried out by the authors generally supported the findings described by Dubois et al. Comparative scale room and simulation data was collected for a dormer window using the same techniques as described above for the roof windows. In particular, the ADF for roof window was found to be 2.9 times that of a dormer window of identical roof aperture size and head height. 3.7 Energy consumption As far as the predicted energy consumption is concerned, the available techniques are rather more limited. Given the project duration, it was impractical to consider collecting data from a real loft room over an extended period. Energy consumption data from scale rooms is generally not considered particularly valuable and in any event it was expected the proportionately small change in energy consumption with changes in roof window area would potentially be masked by experimental error and measurement limitations. The use of the Apache thermal simulator appeared to offer the most promising option for predicting annual energy consumption and was applied to a number of test cases. From this simulation, it was apparent that the range of values for annual energy consumption are much less sensitive to changes in roof window area than is the case for daylighting levels. For the typical example that was analysed, varying the roof window area from zero to 20% of the floor area resulted in a maximum variation in energy consumption between 1830kWh and 2330kWh or 21% of the maximum value. The minimum total annual energy consumption was with a glazing to floor area ratio of between 13% and 17%, depending on the orientation of the loft room.
4 Comparison of tactics Calculation of daylighting levels for loft rooms using a single stage method was comparatively rapid but it appears that the usual calculation method will tend to underestimate the daylighting performance of roof windows. The use of scale rooms under artificial sky conditions provided access to daylighting prediction based on variables that would not routinely be possible in full size rooms. Obvious instances of this flexibility included variation in the window area and the ability to change from a dormer to a roof window at will. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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The collection of data under the artificial sky represented a very stable and repeatable test environment, without the variability of weather conditions. The scale room was intuitive to use and provided good quality data, albeit typically at a resolution that was limited by the scale of model and the precision to which the model had been constructed. The majority of these observations are consistent with those described by Littler [15]. In contrast, the simulation techniques allowed for finer resolution and provided photo realistic rendering data. In order to obtain valid data, it was important to construct a CAD model that accurately reflected the room under investigation. The simulation tools also required care during the setting up phase to ensure that the results reflected reality. The use of a common data model within the IES Virtual Environment was also valuable as it facilitated a comparison of the Radiance and FlucsDL results for the same CAD model. The measurement activity generally affirmed the qualitative findings from the calculation, scale modelling and simulation work. It also directly related the findings to a real environment and highlighted some of the intrinsic issues in the measurement of lighting levels in a practical context. Although the data set was small, from the measurement work it did seem that in some cases the actual daylighting performance of roof windows might exceed that predicted by scale rooms or using simulation techniques. From a practical point of view, the challenge in the measurement work was one of normalizing the recorded results in order to try and eliminate the effects of any minor variations in aspects such as reflectance and geometry.
5
Design tool
A derived objective of the project was the preliminary development of a simple graphical design tool to exploit the research. This tool is intended to assist homeowners and designers in sizing suitable roof windows that optimise both the daylighting and energy consumption aspects. It is based on two graphs that plot the linear change in predicted ADF and the U shaped variation in energy consumption with increasing roof window area. This tool will apply to a reasonably common set of conditions for aspects such as roof pitch, construction type and location.
6
Conclusions
This paper makes a case for amending the current guidance on roof window sizing and also the stated relative performance of such windows in comparison with dormer windows. Rather than suggesting 10% of the floor area as the minimum for adequate daylighting, it appears that for typical loft rooms a roof window sized at 7.6% of the floor area will actually provide optimum daylighting levels. Roof windows have been confirmed to provide daylighting levels that are approximately three times better than equivalent dormer windows, which may sometimes encourage their preferential selection for visually sensitive situations. Lastly, in the case of specifically low energy designs and WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
358 Eco-Architecture: Harmonisation between Architecture and Nature assuming adequate control mechanisms, roof windows having a glazing area that is between 13% and 17% of the floor area may be the most energy efficient solution.
References [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14]
[15]
Hopkinson R G, Petherbridge P and Longmore J., Daylighting, Heinemann, London, pp. 59-107, 1966. Littlefair P J., Site Layout Planning for Daylight and Sunlight: a Guide to Good Practice, Building Research Establishment Report, Watford, 1991. CIBSE., Lighting Guide LG10 Daylighting and Window Design, Elsevier, Oxford, pp. 15-68, 1999. Baker N and Steemers K., Energy and Environment in Architecture, Spon, London, pp. 22-25 and pp. 42-52, 2000. Velux Ltd., Loft Conversion Guide, Velux, Glenrothes, pp. 29-31, 2003. Hymers P., Home Conversions, New Holland, London, p. 85, 2003. Velux Ltd., Directors Report and Financial Statements, Velux, Glenrothes, pp. 3-9, 2004. Office of the Deputy Prime Minister, English House Condition Surveys, 2003 and 2005. British Standards Institution, BS8206 Part 2 Code of Practice for Daylighting, BSI, London, pp. 2-7, 1992. Borer P and Harris C., The Whole House Book, Centre for Alternative Technology, Machynlleth, pp. 35-36, 1998. Velux Ltd., Architects Binder, Velux, Glenrothes, 2005. Ward Larson G and Shakespeare R., Rendering with Radiance – The Art and Science of Lighting Visualization, Morgan Kaufmann, San Francisco, 1998. Integrated Environmental Solutions Ltd., Virtual Environment Version 5, Integrated Environmental Solutions, Glasgow, 2003. Dubois M C, Grau K, Traberg-Borup S and Johnsen K., Impact of Three Window Configurations on Daylight Conditions: Simulations with Radiance. Internal Report, Danish Building and Urban Research, Hørsholm, Denmark, 2003. Littler J., Test Cells: Do We Need Them? Building and the Environment, volume 28, Pergamon Press, London, p. 222, 1993.
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Section 7 Building operation and maintenance
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Building defects: survey and impact over sustainability E. Costanzo Laboratory for Construction and Conservation LCC1-EPFL, Ecole Polytechnique Fédérale de Lausanne, Switzerland
Abstract It is commonly assumed that existing building stock management has a great potential to achieve better sustainable development results. Durability of existing building components determines the period of their performance decay and, therefore, maintenance and refurbishment cycles, which, owing to their recurrence, may have relevant effects on the environment and the economy. Knowledge of building pathology phenomena and, therefore, defects prevision during building operation, can lead to less frequent and more appropriate maintenance and renovation, helping lengthen service life (and durability) of components, and so avoiding new production and construction impacts and reducing recurrent C&D waste due to frequent replacement. This paper shows the advantages of an archive on building pathology, created from cases of expertises and consultancies, and a proposal of a protocol of survey, to collect in-field data and address the use of the archive towards operational and post operational building performance assessment and management. Keywords: construction elements, failure, survey, post occupancy evaluation, durability, indoor health.
1
Introduction
The operational phase in building life is the moment where the occupant has to experience and to profit of the existing structure. This phase lasts at least 50 years in average and is the very aim of construction, where the user’s needs are compared with real building performances and their eventual decay due to aging: WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060361
362 Eco-Architecture: Harmonisation between Architecture and Nature health, safety and security, functionality and efficiency of technical and space elements • psychological, social, cultural and aesthetic performances. Moreover, - if we consider an existing building as an heritage all citizens has to profit of as enlarged users of the built environment - environmental and economic issues, such as impacts on natural material and energy resources consumption due to operation, land occupation, adaptation to present crucial uses and other externalities, are also to be taken into account. Since the ‘1970s Post Occupancy Evaluation (POE) models have been developed to estimate real occupancy performances of housing rapidly constructed after the Second World War, when premature damages and degradations began to be evident. The feedback evaluation of performances and failures has several advantages: • socially, to demonstrate lacking of knowledge of needs, expectation, behaviour and lifestyle of present occupants at the age of construction; • technically, to assemble useful information on design, construction and renovation “correctness”, thus contributing to assess service life [1] and negative effects of building components and products. The feedback data are precious to building industry, to maintenance and management planning, to the assessment of compliance to new standards that occurred after the construction. It is the case of energy saving directives but also of building products health and environmental standards, nowadays more and more imperative in Europe [2]. Information from inspection of buildings, - when the investigations are properly designed - gives direct correlation between the state of components, exposure environment and the building use [3]. The trend for systematisation of such information is alighted by recent international acts and procedures and by the spread of master study courses for surveyors: i.e. the UK 2004 “housing act” requiring re-launched training for building inspectors [4] and the on going “air quality campaign” in France [5]. Failures that occur in buildings are among the data that are necessary to gather in order to evaluate varied building performances from the design phase. The concern of measuring the relationship between occupants’ satisfaction and building technical performance is expressed by recurring complaints on comfort deficit (acoustic and lightning levels, temperature and humidity, ventilation, indoor air quality) as consequences of components failures or inapt employ of materials and techniques. Quantitative and qualitative evaluations are necessary to attain the comparison between measured and perceived levels of performance. Expertises supplied by EPFL for thirty years in French Switzerland, as a service to owners, architects, building estate managers, renters and lawyers constitute an archive basis on actual state of running modern buildings. The available database contains information on corrupted materials, components failures, performance decay, agents, anomalies localization, factors causing degradations, defects and responsibilities. Most of pathologies have been found to be systemic, first of all the ones where components failures and low indoor comfort are strictly related [6]. • •
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Nevertheless our available information should be enriched by a more systematic approach in measuring micro-environmental loading, building components degradation and in investigating occupants’ perception. The relationship between these three factors is still unexplored, as well as effects on human health due to indoor pollutants; yet some of them are generated by building products and by their degradation. Therefore we consider it necessary to broaden the building pathology enquiry field, fostering the interdisciplinary approach of three combined issues: socioeconomic occupants’ satisfaction, environmental and engineering studies of indoor environment, architectural topic of components’ durability.
2
In field data collection
Survey is the first cognitive moment of the building, of its components features, of their aging and use conditions but also of performance level they actually supply. It can represent much more than a simple “visual appreciation” so leading to diagnosis, if the surveyor carries it on according to a procedure and by help of a basic equipment that allows him to gather numbers of targeted information. Normally a first recognition visit is followed by a more detailed direct survey, where adopting further diagnosis-oriented investigations and non-destructive or little invasive tests and monitoring. The surveyor analyses: • Materials and their labour • Constructional techniques and historical stratification • Degradation phenomena and evolution • Triggering agents • Hygienic-sanitary conditions, health and comfort (IAQ, IEQ) Moreover further instrumental testing, technically more complex and expensive, may claim particular skills and experience. Decision to deepen the diagnosis is established by the surveyor and can be rather subjective. An indiscriminate adoption of such methods might be a burden for a cost-effective diagnosis, and for repeatability of building performance evaluation methods. It is necessary, in our opinion, a rule to scientifically define the relationship between the presence of particular building materials and products, their degradation, health concern and measurable in use performances. In the last decade different campaigns in Switzerland dealt with building pathology diagnosis and indoor comfort, supplying separate tools of building performance evaluation [7] [8]. We are working at a tool, a protocol, to make the survey methods repeatable and to integrate available information in our building pathology database. 2.1 Preliminary recognition visit During the first visit, following a quick documentary research and simple questions to owners, clients, occupants, the surveyor will gather general data and attain a rough estimation, by the aid of descriptive forms. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
364 Eco-Architecture: Harmonisation between Architecture and Nature Table 1:
General data for report of preliminary recognition visit.
Data to report: Conditions of engagement Data on client Client’s mandate or complaint Geographical information Building localization Date of inspection and weather Functions of the building Date of construction Date of renovation - maintenance Activities per space/room of inspected units Occupational density Demographic information of occupants (position, age, gender, education) Presence, type, conditions of services (electrical, gas, cold water plumbing and sanitary fittings, hot water, drainage) Main technology (prefabricated, Hi-Tech mechanic assembly, main structural and envelop materials) Rough evaluation of overall building components conditions i.e., roofs, chimneys, flashings, parapets, gutters, main walls damp proof courses and ventilation, joinery and woodworks, decorations and finishes, ceilings, walls and partitions, floors, joinery and woodworks. Rough evaluation, rating of degradation percentage and level Pre-diagnosis
Eventual degradations will be rapidly appreciated according to four levels: light, average, heavy, irreparable and by rough estimation of percentage or number of components affected by degradation. A first pre-diagnosis will be hypothesised, also underlining opportunity of further survey. 2.2 Building defects detailed survey: protocol of investigation The tools that compose the protocol in course of development are: 1. A check list for sensorial survey, mainly subjective visual, odour, tactile, noise assessment, to gather qualitative data on presence/lack of symptoms and anomalies (Figure 1), as well as on presence/lack of building products that can be sources of indoor pollution such as fibrous or foam insulations, textured paints and coatings, pressed wood products, wet or damp carpets, tissues, glues, some rocks, etc [9]. 2. A questionnaire for occupants. (Table 2) Aid tools for more detailed inspections are: 3. A list of reference to methods of direct survey. The surveyor uses common instruments such as insulated light and extension lead, binoculars, plumb line, hand mirror, camera, assorted screwdrivers, digital level meter for angles and gradients, laser measurer, capacitance moisture meter, endoscope, rubber tipped hammer, metal detector and stud sensor, concrete reinforcement corrosion detector, inflatable bags and smoke testing, coloured dyes for tracing drain runs, but also more specific equipment [10] for measuring materials strength or detect invisible condensation (dew point indicator). (Figure 2) 4. A list of reference to instrumental procedures of testing and monitoring to quantify IEQ effects due to building components pathology or inappropriate use of building materials, absorbing or emitting ozone, formaldehyde, fibres, asbestos, radon, bacteria and moulds, VOCs.
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Sensorial Perception: • Visual: Colour, surface texture, continuity, deformation • Tactile sensation: Temperature, moisture content, consistence (tenacious, friable); hardness (tender, soft, hard) • Sound: different sound levels at impact • Taste: salted (efflorescences); sweet, bitter, none • Odour: acre, sweet, Questions to Surveyor perception Visual sensation occupants A) Ceiling Finishes. (code 45/1) Visual sensation: Material: Plaster Where water leaked? How long have Moisture stains and corrugation Are there interior or exterior stains? What is their chromatic attribute? What water leaked? of rendering the degrees of intensity? What the Since when in a degrees of brightness (clear, dark)? visible way? Does it make patterns along fissures, What were the sills, roof drains? Are there water patterns in efflorescences (white stains)? the building Is the surface flat, smooth, corrugated, history? cracked? What are the materials at Under what perception? What materials-parts were meteorically wetted? What are the materials affected condition leak occurs: after B) Suspended ceiling (code 45/3) by anomalies? Are previous repair present? Are there open or corrupted abundant rain, Material: gypsum-board joints? with what combination Rust stains on the ceiling wind-waterfall?
Figure 1:
Example of checklist for sensorial survey in two cases of water leak trough flat roof.
Existing checklists, building codes, standards and past good practices form the references to outline questionnaires for owners, managers and occupants [11]. Table 2:
Abstract of the questionnaire for occupants.
Data and evaluations to be supplied by the occupants Comfort per type of space (rated from 1 to 4, according to different spaces/rooms) Scores for temperature, ventilation, humidity, air movement, air freshness, odour, noise distraction, visual privacy, conversation privacy, natural and artificial lighting comfort, glare from light, perceived quality of building materials Functionality of components: Scores: easy (simple, intuitive) to use, equitable use (for different abilities), resistant, safe. Maintainability: easy to care, difficult to care, frequency of maintenance Ecology: energy saving (bill cost, Energy Index), kind of cleaning, frequency of cleaning Health problems: allergies, headaches, light disturbs (complaints, frequency of disturbs)
During the detailed inspections the pre-diagnosis is confirmed or rejected. This may require the use of instrumental testing that is to be indicated by the surveyor himself. He has to judge the opportunity and the kind of such check. Figure 2, case A, illustrates the characterisation of symptoms like stains, WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
366 Eco-Architecture: Harmonisation between Architecture and Nature efflorescence, and moulds. One third to one half of buildings have damp conditions that may encourage development of such pollutants, often causing allergic reactions - including asthma - and spread of infectious diseases. Related symptoms described by occupants may be sneezing, watery eyes, coughing, shortness of breath, lethargy, fever and digestive problems. Owing to the correlation of factors like temperature, relative humidity, thermal transmittance, condensation and probable presence of indoor air pollutants (VOCs, formaldehyde, moulds, odours) in this pathology case, the surveyor might go through the indicated instrumental monitoring. More generally, building products can actively and indirectly contribute to pollution not only as a source of indoor pollution but also by absorbing or reacting to NOx, SOx, CO2.
3
Impacts on sustainability
Life cycle thinking is peculiar in sustainability evaluation. Within this approach building pathology distresses: • Mentioned health and satisfaction of occupants during operation • Functionality of components • Service life of the original and repaired components, hence waste avoidance • Degree of repair intervention and through time easiness to care. • Reusability or recyclability of components when dismissed and their end of life treatment (discharge, incineration, special processing, etc.) Choice of materials and of their quantities, also due to repair frequencies, determines associated environmental impacts. That’s why service life, is mentioned as a parameter to be taken into calculation of resources consumption and emission flows [12]. Knowledge of negative cases and codification of failure modes, contributing to service life prevision, effects on micro-environmental and occupants’ comfort, can improve sustainability performances.
4
Results
The ongoing work, as illustrated, will converge to a method of data collection to integrate components pathology analysis with occupational and indoor environment information, within a holistic approach to building performance evaluation.
5
Conclusions
Data gathering during expertises on building pathology is to standardize, in order to have replicable results and contribute to post occupancy evaluation.
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Direct survey • Materials and degradation classification and evolution with weather (see sensorial perception checklist) • Dimensions of the room/space • Orientation of the wall • Orientation, position and size of doors – windows • Appraise detachment and moulds stain surface (rating) and position • Evaluate relationship with Case A: thermal bridges Detachment of the paper, stains, (external insulation, moulds, fungal growth, Odour presence of reinforced concrete beans and Pre- diagnosis: columns) • Insufficient thermal • Verify insulation of the wall (U value) presence, type and • Excessive air-tightness of position of thermal the windows insulation in the wall • Excessive air moisture content (but also in the floor in the room (insufficient and in the ceiling) ventilation) Presence of materials with air pollutants emissions: • Glues (VOCs) • Tissues (formaldehyde) • Tissue powders (fibres)
Instrumental testing Material characterisation (destructive sampling): i.e. organic nature of coating and of glue. Moisture content, wall moisture meter Surface temperature hand kit Thermal Bridges hand thermograph Temperature and Relative Humidity (ISO 7730) instantaneous measurement by a Fanger psychrometer. Condensation (ISO 13788) Air tightness of windows pressure-pulsation by a standard kit with ventilator Formaldehyde airborne concentration by passively samplers (ISO/DIS 16000-4) and analysis by chromotropic acid colour development UV-VIS spectrophotometry. Moulds analysis on specimens taken from surface (Petri Box) and from air (pumping on polyurethane foam) VOC analysis by diffusion sampling and gas chromatography (ISO 16017-2)
Check activity and evolution of fissures at visual and probe (indoor-outdoor) Presence of materials with possible dangerous emissions: • Isolating mats behind the gypsum Case B: boards (fibres) Displacement and fissures between the indoor gypsum boards Pre- diagnosis: Shifts of the load-bearing structure
Sequence and composition of the wall layers (endoscope) Cracks width and evolution (monitoring through time by a plaster or glass crack indicator) Mineral fibres monitoring of airborne concentration by pumping air into filters or by a hand counter of condensation centres (CNC)
•
Figure 2:
Examples of detailed inspection checklist.
WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
368 Eco-Architecture: Harmonisation between Architecture and Nature A more rigorous approach in surveying can be put to point by putting into practice a campaign of oriented expertises. These ones should simultaneously take advantage of empirical and scientific methods, both direct sensorial ones, which are peculiar of current building pathologies inspections - and instrumental monitoring, typical of IEQ building physics and chemical investigations. Furthermore, a sustainable approach cannot neglect interviews to occupants and their appreciation. In some standard cases, as the presence of moulds and water leak, such approach could allow fixing: • Reliability of pre-diagnosis survey visit • Proper testing and a standardised series of empirical detection procedures • Relationship between qualitative pre-diagnosis direct survey results and quantitative measurement.
References [1]
[2] [3]
[4] [5] [6] [7] [8] [9] [10] [11] [12]
International Organization for standardization, series ISO 15686: Buildings and constructed assets - Service life planning. ISO 156861:2000 General principles; ISO 15686-3:2002 Performance audits and reviews; ISO 15686-6:2004 Procedures for considering environmental impacts. European Commission Construction Unit, http://europa.eu.int/comm/ enterprise/construction/mission_en.htm. P. Jernberg, C. Sjöström, et al., Service Life and Durability Research, Proceedings of Joint CIB W080/RILEM TC 140 -Prediction of Service Life of Building Materials and Components - Guide and Bibliography to Service Life and Durability Research for Buildings and Components, Part I, CIB report 295, 2004. BRE, British Research Establishment, http://www.bre.co.uk/. Observatoire de la qualité de l’air, http://www.air-interieur.org/. F. Iselin, Plaidoyer pour des rénovations durables - Leçons de mille et une expertises. C&R 5, pp. 52-56, May 2005. Publications of Programme PI-BAT, Entretien et rénovation des constructions, Office Fédérale des Questions Conjoncturelles, Berne 1990-95. Office Fédéral de la Santé Publique, Liste de contrôle pour la première évaluation de la charge polluante à l’intérieur des bâtiments existants, Berne, Suisse, 2000. Ibid., Fiches d’évaluation : fiches thématiques et de matériau (20 sheets) P. Glover, Building Surveys, Elsevier: Oxford, pp. 4-6, 2003. W. F.E. Preiser, J. Vischer, Measuring instrument for Building Performance Evaluation (Appendix), Assessing Building Performance, Elsevier, pp. 209-237, 2005. AFNOR, NF P01-10:2004, Environmental Quality of construction products – Environmental and Health Declaration of Construction Products (Within the ISO/TC59 for ISO/TS 21931). WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Cob seismic rehabilitation G. Scudo1 & A. Drei2 1 2
Department BEST, Politecnico di Milano, Milano, Italy Department Ingegneria strutturale, Politecnico di Milano, Milano, Italy
Abstract Among the different earth architectural techniques largely diffused in the Italian regions – rammed earth, various types of “adobe”, light earth and cob – the last one is the less known due to its prevalent use in traditional rural buildings and in a few small settlements in Central Italy, partially abandoned in the last 50/60years. Only recently the administrations of the Regions where the majority of this cultural heritage is located developed an interest in the cob technique and earth architecture, mainly in the Marche and Abruzzo regions. Conservation and ecological interest are the main aim of the local groups which have to face the very “heavy” task to cope with national technical norms, particularly seismic ones which do not include traditional earth based building technologies. A detailed study has been carried out to assess the technological and structural pathologies of a typical rural residence in Treia (Macerata Council, Marche Region) now abandoned in critical conditions due to the lack of maintenance and to the destructive use of concrete and bricks in previous repair interventions. An appropriate technological and cultural sound restoration was proposed along with a structural improvement taking into account the seismic hazard of the area, by means of a wooden grid included into the outside façade of the cob structure. Seismic forecast performance of the proposed system is based on the experience of the Colombian research group “Tierra Viva Foundation” and was also studied by means of a numerical modelling. Keywords: earth construction, seismic rehabilitation, cob technique, rural residence.
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1
Context
The understanding of earth building seismic behaviour is an important issue also in Italy, where existing large earth built Cultural Heritage stimulated a proposal to introduce into the new seismic national regulations earth material and techniques. The rehabilitation design of an earth building has been the occasion to study its antisismic performance through specific “consolidation” techniques. The opportunity came from the interest of the Treia council in Macerata County (Central Italy) and local architects to preserve the cultural heritage of an almost disappearing earth technique common in that area. The local Council promoted an agreement with the property to repair one of the few still standing cob buildings (“atterrato” Cerioli) in Treia through a “learning by doing” process which involves researchers, architects, local technicians and builders in the frame of a larger rehabilitation programme.
2 Cob technique The unique earth technique used in Treia is the cob (“massone” in Italian, “bauge” in French) which is relatively uncommon in Italy where the most diffused earth techniques are rammed earth and earth blocks. In Italy cob technique is limited to few areas in the hinterland of Marche and Abruzzo regions (central Italy), while in France, Belgium and Great Britain the cob cultural heritage and new cob buildings are much more diffused and studied [1, 2]. The existing cob architecture in Marche region – built between the second half of the XIX century and the beginning of the XX – is mainly rural isolated buildings, now almost completely abandoned; a unique example of row houses – Villa Ficana settlement – now inglobated in Macerata town and undergoing to a rehabilitation programme – is still existing [3]. Cob is based on the traditional ingredients of many other earth techniques: aggregates (vegetal fibres, small stones, gravel, sands and silts), binder, which is the clay fraction of the soil, and water. When the wet mixture is done, walls are built directly without any shutter or formwork. In the traditional technique the cob mixture is used to prepare the “massoni” (big “earth loaves”), which are put beated on the wall. The single course is more or less one meter high and has to be enough dried to “carry” the second course. Up to two/three courses, the vertical surface is then pared with special cutting devices used in agricultural works (mattocks, slashers).
3
Seismic protection of the “atterrato” Cerioli
The building is completely built with the earth cob technique, from which comes the local name “atterrato”. The southern part of the building, the oldest one built around the middle of the XIX century, is single store, while the northern two WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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stories part was added later defining a non regular typology uncommon in the area (Fig 1).
Figure 1:
The cob built “atterrato” Cerioli in Treia (Macerata Council, central Italy).
When the design analysis and restoration proposal were carried out (2 years ago), the building was in a very critical physical decay due to structural and technological pathologies determined by a long period of lack of maintenance, wind and rain actions and soil yielding (Figs 2, 3).
Figure 2:
Analysis of the structural pathologies due to soil yielding and lack of maintenance.
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372 Eco-Architecture: Harmonisation between Architecture and Nature
Figure 3:
Analysis of wall erosions due to wind, rain and lack of maintenance.
Earth building techniques generally give structural elements which have a lower carrying capacity in comparison to other poor conventional techniques such as multiple-leaf walls. Further on the flexural behaviour of earth cob structures, even if it can be considered a monolithic element, without mortar joints, is not good because of the low tensile resistance of the material. Therefore the overall structural performance requires a high thickness of the earth structure, usually not less than 40 cm. Nevertheless earth structures have a relatively good ductility behaviour, which is very important to resist seismic actions, while masonry structures have generally very low ductility factors. The plan to insert earth structures in the national seismic code came up against a certain opposition, mainly based on the critique (or pre conception) that it was very difficult to include in a technical regulation the great variability of mechanical properties of earth structures due to the local differences of soil ingredients and craft-men culturally oriented building abilities. It is a typical example of local/global technological conflict in which the dominant methodology have to rule over the local knowledge and experience: i.e. durability standard analysis (as defined by RILEM standards) requires an elevated number of water immersions which is good for water resistant building materials (i.e. concrete for dams, etc.) but not for many other which are never exposed to continuous flooding. The critical problem of conventional earth building technologies performances – such as cob or other earth technologies – needs to be faced through a transdisciplinary and culturally oriented approach which keeps
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together local experience with architectural, technological and structural requirements. Focusing on seismic protection of diffused earth architectures, since a few years many proposals and experimental techniques have been carried out. The first studies on seismic reinforcing of earth buildings have been performed in South America where earth blocks (“adobe”) and rammed earth (“tapial”) techniques are largely diffused in highly seismic areas. The main researches have been done by the group CERESIS [4], by the Getty Institute and by Gernot Minke [5]. The results where diffused also through very simplified guidelines which are very useful in such contexts. More recent studies have been carried out by a professional group (“Tierra Viva Foundation”) in a collaborative research project with the Getty Institute. The group experimented with a seismic reinforcement made by a wooden lath grid which can be integrated in different parts of the earth structure (outside, inside, only in corners): the wooden grid reinforcing system is easy to fit to the existing earth structures, and therefore it is a valid alternative in seismic areas to the diffuse inappropriate use of reinforced concrete or steel elements additions, which are not physically compatible with earth structures and often produce damages in earth buildings by strong earthquakes.
4
Rehabilitation and seismic reinforcing technology
The proposed rehabilitation follows two guidelines: first the preservation of the original architectural characteristics, (dimensions, position of inner walls, doors, windows, stairs) through conservation and repair; second a more invasive but anyway reversible and low-cost structural consolidation to increase load carrying capacity in case of earthquake. The preservation of the original building implied the limitation of the technical plants inside and the location of services out of the cob building, the ridding of degradation causes (ventilated French drain, outside drainage, renewal on the roof) repair and reinstatement with cob of the heavy dilavated external walls. A special earth stabilized plaster has been studied to protect by water erosion the outside cob walls. Consolidation design involved also the site of the building with a soil retaining wall, to avoid further yielding causing heavy structural cracks. Following the basic design choices and to eliminate the inconformity among materials, every additional previous intervention (brick, concrete, etc.) to close cracks and cavities was removed and replaced with the traditional cob. The stairs, previously a brick structure, and the intermediate floor were completely rebuilt, using only wood elements. The floor beams were connected to the walls with an intermediate wood plate, in order to distribute the load and to prevent stress concentration on the earth walls. The same solution was adopted for the new roof. The proposed intervention was aimed to use materials and techniques suitable with earth structures and to avoid any structural hardly reversible superimposition such as brick buttresses, concrete columns, concrete slabs WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
374 Eco-Architecture: Harmonisation between Architecture and Nature applied on the walls, corner brick reinforcements, reinstatement with steel grids and concrete, etc. All these “hard” techniques, very often used to reinforce masonry structure, are non suitable for the conservation of earth buildings or for their seismic upgrading. The very different stiffness of the coupled materials strongly modifies the overall physical and structural behaviour of the building.
Figure 4:
Seismic action on original earth structure - VM stress.
The enhancement of the performance to seismic actions is based on the adoption and deepening of the techniques proposed and experimented by the Columbian research group “Foundation Tierra Viva”. A numeric modelling confirms the effectiveness of the adopted methodology (Figs 4, 5). A reinforcement grid made by vertical and horizontal wood joists at a distance of about 100÷120 cm is applied to the external walls. It can be modified following openings position but anyway maintaining the density of reinforcing grid almost uniform in the different walls; some diagonal joists are inserted for bracing (Fig 6). Moreover, in order to obtain a better global box behaviour, the wood frame should be connected by screws to the wood beams of the intermediate floor and to those of the roof. This last union is important for the reinforcing of the tympana, which are generally the first elements to collapse in the experimental tests performed by the research groups previously indicated. The critical details of the grid system are the joist joints, the connection at the building angles, the fixing to the ground of the vertical wood elements. The joist union was designed as a simple placement side by side on a wood table under them, fixed to the table with wood pins. The grid connection at the angles is made by steel angle bars.
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Figure 5:
Figure 6:
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Seismic action on grid reinforced earth structure – VM stress.
Design of the reinforcement wood grid integrated into the external walls.
The fixing to the ground of the vertical splints is made by means of bent steel plates fastened to the wood elements and drowned in a concrete stringcourse at the base of the earth walls. This buried external stringcourse is important also to reinforce the base of the “atterrato” which is completely made with earth cobs, and has no foundations. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
376 Eco-Architecture: Harmonisation between Architecture and Nature In other cases, these kinds of earth buildings have a stone or a brick masonry basement, acting as foundation and protection from soil water. The proposed reinforcing is for many aspects similar to the “sistema baraccato” a building system proposed by probably the first Italian seismic code, at the end of the XVIII century in the kingdom of Naples. It consisted, in brief, in timber frames well connected, with stone/brick masonry inside. Another important detail is the protection and the strengthening of door and window openings by means of complete wood frames, connected to the external grid. Even if the external grid is not adopted, the protection of the openings is quite important, because the beginning of fractures and crashing happens generally at the angles of doors and windows, due to stress concentration. Finally the grid can serve also as a support for the earth plaster. The effectiveness of the intervention was evaluated by a numerical modelling, to investigate the most stressed zones of the structure and of the grid. The analysis was performed considering the seismic spectra of the Italian norm for Treia. The applied grid, assuming the adhesion of the joists to the earth walls and an effective fixing to the ground, yields a good performance; the model suggests also an additional reinforcing (other vertical elements) near to the angles, where there are larger stresses. The global effect obtained by the grid is a 30- 35% lowering of the maximum stresses in the earth walls.
5
Conclusion
The conservation of the architectural heritage was the aim of the project as the “atterrato” Cerioli is protected by local regulations, therefore the original configuration was not modified. Guidelines of the restoration design were the use of eco-compatible materials, fit for earth cob constructions, and a structural intervention for seismic protection made with low-cost and low technology materials which can be removed. Nevertheless the global good behaviour that can be obtained, depends especially from good craft-men capability and a high quality technical direction, that is in paying attention to the details of the project (mainly the connections between the elements and to the ground) and in an accurate work execution. The house services and the technical plants, necessary for the use of the building, will be located in a new small construction made with pre-cast cob elements, in order to test also the modern evolution of this traditional technique.
References [1] [2]
A.A.V.V., Architecture de terre en Ille-et-Vilaine, Ed. Apogée, Ecomusée du Pays de Rennes English heritage research transactions, Earth- The conservation and repair of Bowhill, Exeter: Working with Cob, Vol.3, English heritage Ed., London, 1999 WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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[3]
[4] [5]
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Saracco M., Architettura in terra cruda: il caso delle Marche, Alinea Ed.,Firenze, 2002. Scudo G., Sabbadini S., Le regioni dell’architettura in terra, Maggioli Ed., Rimini, 1997. Scudo G., Sabbadini S., Bonomini A., Drei A., Il recupero ai fini antisismici del massone, il Progetto sostenibile, n°8, Edicom 2005. CERESIS, Centro Regional de Sismología para America del Sur, founded in 1971 by Argentina, Bolivia, Brasil, Colombia, Chile,Perù, Trinidad, Uruguay, Venezuela. Minke G., Construction manual for earth quake-resistant houses built of earth, Ed. GTZ. Nuevas casas resistentes de Adobe, Pontificia Universitad Catolica del Perù Centro International de Investigation para el desarollo (CIID).
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Section 8 Water conservation
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Rainwater harvesting in Brazil: investigating the viability of rainwater harvesting for a household in Brasília D. Sant’Ana Oxford Institute for Sustainable Development, Department of Architecture, Oxford Brookes University, Oxford, UK
Abstract This paper addresses the issue of harvesting rain for later use, as part of a decentralised sustainable urban water management scheme, by adapting an existing house in order to study the viability of rainwater harvesting (RWH) systems. The goal of this study was to investigate the potential solutions for the application of a domestic RWH system for a household in Brasília and identify the most favourable system for such, considering water conservation and its economic viability. Based on the investigated the household’s total annual water consumption and rainwater yield capacity, two RWH systems were proposed: a treated and a potable indirectly pumped system. The treated RWH system, used for toilet flushing, dish washing, clothes washing and sink washing, is capable of conserving 222.65m3/yr of potable water. Considering the total annual savings of R$1,962.54 (US$882.71), this system has a payback period of approximately 11 years. The potable RWH system, applied to the existing plumbing, supplies potable rainwater into a pre-existing water tank for all uses. This system presented a lower payback period of 9½ years, is able to conserve 456.25m3/yr of mains water and contains a total annual savings of R$3,659.29 (US$1,645.88). The potable RWH system conserves more water, and has a lower payback period than the treated RWH system because it harvests and uses more rainwater. Although, there is a setback, the potable system contains a much higher capital cost and operational cost, requiring a higher initial investment capital and annual expenses. Keywords: rainwater use and harvesting systems, rainwater tank performance, potable water savings, cost-benefit analysis, viability of rainwater harvesting in Brazil. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060381
382 Eco-Architecture: Harmonisation between Architecture and Nature
1
Introduction
Water is the most precious of all resources, to sustain it, is to preserve life. According to the Agencia Nacional das Águas -ANA (National Water Agency), it is estimated that the capacity to supply fresh water to the city of Brasilia will be exhausted by 2007 [1]. In order to meet the demand, the construction of a fifth water catchment system, the Corumbá IV water dam, is taking place. The implementation, operation and maintenance of large scale systems are becoming complex and costly. Because of this, most environmental specialists believe that future urban water management will have to be decentralised, with small scale systems such as rainwater harvesting, in order to preserve and maintain precious ecosystems threatened by the large scale urban water and waste management schemes. The exploitation of further hydrologic resources, as well as being environmentally unfriendly, could only solve the supply issues for the city on a mid-term level. The actual problem lies within the exceeding water consumption of the city, where for example, the enormous water consumption rate of 829L/person/day at the Lago Sul neighbourhood of Brasília [2] is four times larger than the generous average quota of 200L/person/day estimated by Gould and Petersen [3]. Collecting rainwater from buildings is a simple concept promoting selfsufficiency, water conservation and minimises local erosion or flooding caused by run-off. A mass scale use of rainwater harvesting on buildings may possibly aid on minimising the impact of floods on cities as well as reducing the demand of freshwater by storing storm water to be consumed later on. Precipitation has the advantage of being relatively pure, oxygenated and free. Treated rainwater can be safely used for toilet flushing, washing and irrigation [4]. Therefore the use of rainwater on buildings could play an important role on water conservation and sustainability.
2
Objective
The idea of retaining rainwater for reuse as part of a decentralised sustainable urban water management scheme for the city of Brasília, addresses the issue of adapting existing buildings in order to apply such systems. This study shall investigate the possibility of adapting a typical house at Lago Norte, as well as identifying the optimal rainwater system for it. Formulating the possibilities of rainwater system for domestic supply depends largely upon its water consumption patterns and the volume of gathered rainfall. As the price for water rises, due to the limited offer and the growing demand, a cost-benefit analysis linked with the amount of water harvested and therefore conserved, should also be analysed in conjunction with the system’s cost. The overall aim of this investigation is to analyse the possible solutions towards the application of a rainwater harvesting system for a house in Brasília, Brazil and pinpoint its optimum harvesting system considering water conservation and feasibility.
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3 Methodology Initially, with the intention of determining the optimal rainwater harvesting system for the investigated house, an overview of existing system types and possible configurations linked with an estimated annual rainwater yield capacity is necessary. By assembling the site’s rainfall data and assessing the existing catchment area, an estimated monthly rainwater supply can be determined. With this, a cross reference of rainwater supply patterns and possible domestic water demand can be done to propose a potential rainwater harvesting system. The estimated water savings can be obtained through modelling the recommended rainwater system, followed by an annual simulation of monthly harvesting and consumption patterns of rainwater. This simulation shall also assist on sizing the storage tank of the system, considering its security of supply. In order to assess the proposed rainwater harvesting system’s feasibility, the comparison of the estimated total capital cost of equipment and installation together with the cost of mains water saved, provides the predicted payback period of the system at hand.
4
Case study
The investigated five bedroom house, with a total area of 483m2, is located on an 8,000m2 plot of land near the banks of Brasília’s artificial lake, Lago Paranoá, situated in the neighbourhood of Lago Norte. Within the site, a swimming pool is topped up with mains water on the average of once a year. The house is mains connected, receiving potable water from the local water facilities company CAESB, which supplies potable water for a total of six people. This water is fed to a 2,000 litres mains water tank located within the loft of this residential construction, which is later delivered to points of use in the house by gravity. External consumption of water, such as garden irrigation, car and floor washing, is supplied by an underground water well located within the site. The underground water is extracted via water pump and is fed to external taps located throughout the garden. 4.1 Domestic water demand The metered data collected from the investigated house for the period of one year indicates that the average daily water consumption is 1.25m3 from the total annual consumption of 455m3, fig. 1. Having six household members living in the house, the daily water consumption per capita for the period of August 2004 to July 2005 is of 207.8 L/person/day. 4.2 Estimating rainwater supply The average volume (L) of the annual rainwater yield Yt can be calculated by the product of the amount of rainfall (mm) available over a period of time Rt, its possible collection from a catchment area A (m2) in relation to its runoff coefficient Cr and the system’s filter efficiency coefficient Cf [4]. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
384 Eco-Architecture: Harmonisation between Architecture and Nature 36
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Metered mains water readings of the site (m3 per month). Yt = Rt x A x Cr x Cf
(1)
4.2.1 Rainfall data Brasilia’s average annual precipitation is 1,502mm, and its rainfall patterns consists of dense tropical rains during the summer, specially in the months between November to February with precipitation reaching up to the average 250mm, and dry winters, having only an average 5mm of rain in the month of June, fig. 2. 350 300 250 200 150 100 50 0 Jan
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Figure 2:
Brasília’s average annual precipitation. Source: METEONORM V. 4.0.
4.2.2 Catchment surface area The investigated household at hand contains a sloped roof, having a plan area of 468.63m2, and is covered with terracotta tiles. The roof does not contain any gutters and down pipes, therefore the installation of such would be required for a RWH system, which would add up to its final cost. 4.2.3 Runoff coefficient Runoff coefficients of varied catchment surfaces have been developed by researchers and system manufacturers in order to identify the possible rainwater WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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losses of every roof and ground catchment type. Having a sloped terracotta tile rooftop, a runoff coefficient of 0.8 was adopted for the investigated household. 4.2.4 Filter efficiency coefficient With a plan roof area of 468.63m2, the optimal filter for the given situation would be to use a subsurface filter, which is able to deliver filtered rainwater with 90% efficiency for catchment areas up to 500m2. 4.2.5 Annual rainwater yield In theory, the estimated volume of 506.80m3 of rainwater harvested, would be able to completely supply the annual household demand of 455m3. Further investigation of monthly rainwater supply and domestic water demand would be necessary due to the unstable rainfall patterns, where dry months could pose a supply issue. 4.3 Identifying possible rainwater use 4.3.1 Untreated Rainwater Use Untreated rainwater can be used for garden irrigation and external washing. However, in this case, the household already makes use of free underground water for such purposes and therefore investing on a RWH system would bring no pay back. 4.3.2 Treated rainwater use Treated rainwater could be used in the house for toilet flushing, dish washing, clothes washing and sink washing providing some refurbishment to the building is done. By adopting previous studies on water consumption patterns for Brazil [5], where the WC flushing, dish washer, washing machine and washing sink represents a total of 49% of the entire domestic water use, it is possible to estimate the overall volume of rainwater required for such supply. Having a mean annual water consumption of 455m3, for such system, the household would require an average of 222.95m3 of rainwater supply. The overlapping total estimated potential rainwater yield of 507.80m3 implies that, for the system at hand, a partial runoff catchment from the roof area could provide the necessary volume. By using the 228.85m2 portion of available roof area, the total average annual rainwater yield of 247.50m3, would offer the required water volume. 4.3.3 Potable rainwater use Due to a series of possible contaminants and pathogens encountered within rainwater, suitable disinfection is necessary after a microfiltration process, if such water is to be used for potable purposes and other domestic uses such as bathing and washing. In this case, an indirectly pumped system could be easily applied to the pre-existing plumbing with minor refurbishment, by supplying potable rainwater into the existing water tank. Although this would represent a lower cost in refurbishment, safety issues such as electronic fail-safe controls and equipment which are extremely crucial to provide the necessary health safety WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
386 Eco-Architecture: Harmonisation between Architecture and Nature guard, can raise the cost of the system. Another factor to take into consideration for analysing this system’s cost-benefit would be periodical maintenance such as UV lamps replacement and system check-up. 4.4 Proposed rainwater harvesting systems 4.4.1 Treated RWH system The schematic flow diagram of such RWH system represents the design and treatment process of this proposed system, fig. 3. As rainfall is collected by the gutters, an initial screen filtration removes coarse debris as a prevention of downpipe clogging. A subsurface filter provides a finer filtration with a 0.44mm grid and is connected to the stormwater drain pipe, where debris is washed away through a self-cleaning action. The calmed inlet delivers the filtered rainwater to an underground collection tank without disturbing the sedimentation layer of settled impurities, as well as providing slight aeration to the stored water. An overflow unit removes suspended impurities of the water during rainy season, having a backflow protection valve and a grill to prevent unwanted contaminants and animals within the tank. During dry periods, mains water is toped-up to the collection tank when necessary. A float switch located inside the collection tank triggers a magnetic valve, feeding mains water into the tank through the calmed inlet. The floating suction filter provides fine filtration with its 0.23mm filter mesh and extracts rainwater where it is cleanest, therefore reducing the wear of the pump, which is activated by a float switch when required, located within a distribution tank. This water can then be fed to points of use through gravity.
Figure 3:
Flow diagram of proposed treated RWH system.
4.4.2 Potable RWH system The schematic flow diagram of such potable RWH system represents the design and treatment process of this proposed system, fig. 4. This system contains the same filtration process as the previously proposed treated RWH system, but before the filtered rainwater is fed to the distribution tank, disinfection is crucial. Therefore, a 25 and a 5 micron microfiltration is necessary before UV sterilization can take place. In order to guarantee a fail safe system, the WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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ultraviolet treatment unit is equipped with an automatic shut-off control. In case rainwater does not receive the appropriate level of UV radiation, this device automatically prevents the untreated rainwater from entering the distribution tank by restricting its flow. The disinfected, therefore potable water, delivered to the distribution tank, can be fed to points of use through gravity.
Figure 4:
Flow diagram of proposed potable RWH system.
4.5 Sizing the rainwater tank Gould and Petersen [3], indicate a practical and effective graphical method of mass curve analysis to identify the most appropriate tank volume. This method makes use graphics to illustrate the volume of harvested rain and water consumption, over a time interval. By plotting the cumulative average rainwater supply, and cross referencing this information with the average cumulative water demand, it is possible to identify the volume of storage needed. This graphical representation also aids on pointing out periods the tank would need top-up from mains water in order to provide the necessary volume of water. 4.5.1 Treated RWH system tank In order to determine the necessary tank volume for the proposed treated RWH system, a cumulative mean rainwater yield is cross referenced with the average rainwater consumption for the period of one year, fig. 5a. So as to simplify the model, the assumption a constant daily consumption of 0.61m3 is used, given the estimated total 222.95m3 of rainwater consumption for toilet flushing, dish washer, washing machine and washing sink. For one year, the graph demonstrates that from August to November, mains top-up would be required to supply the necessary water for consumption. When this graph is to be plotted for a period of five years, it indicates a progressive rainfall yield compared to the constant rainwater consumption. As a result, mains water top-up would not be required after the simulated second year because by the end of each year approximately 25m3 of rainwater would add up to the following year. Considering that a commercially available 30m3 rainwater tank is applied to the system, its performance is simulated by determining how WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
388 Eco-Architecture: Harmonisation between Architecture and Nature much rainwater it contains through a period of five years, assuming the above supply and consumption factors. Such performance indicates rainwater overflows at its maximum level of 30m3, and after the third year, the tank reaches its maximum efficiency, fig. 5b. 300
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Monthly cumulative supply and demand (a) and rainwater tank performance (b).
4.5.2 Potable RWH system tank Using the same technique as above, a cumulative mean rainwater yield is cross referenced with the average rainwater consumption for the period of one year in order to determine the required reservoir volume for the proposed potable RWH system, fig. 6a. Assuming the total average daily consumption of 1.25 m3, the graph demonstrates that during the months of August to November, the collection tank would be empty and such system would require mains top-up during this period. The five-year simulation of its cumulative supply and demand reveals an arithmetic progression of around 50m3 rainfall yield per year due to annual surplus, compared to its constant rainwater consumption. Due to such progression, mains water top-up is only necessary for the first two years. Considering two commercially available rainwater tanks of 30m3 are applied to the system, the tanks’ performance can be simulated by determining the rainwater volume contained within through a period of five years, assuming the WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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above supply and consumption factors, fig. 6b. Such performance indicates rainwater overflows at its maximum level of 60m3, and after the third year, the tank reaches its maximum efficiency.
5
Cost-benefit analysis
The cost-benefit analysis of the RWH systems includes an analysis upon the total cost of a system, in relation to present and future mains water cost. In order to identify the payback period of a system, its total cost should be divided by the annual savings the system in hand generates. Payback Period (yr) =
Total System Cost Total Annual Savings
(2)
Predicted annual savings of RWH system can be identified by the product of the volume of monthly water saved and the price of mains water within one year, where: 12
Savings (R$/yr) = ∑ (Monthly Volume Saved (m3) x Mains Water Cost (R$/m3)) (3) 1
Operational costs should also be considered in order to obtain a more precise prediction of annual savings. Many RWH systems consume energy, require specialised labour and demand parts replacement. These annual expenses contribute to the deduction of a system’s annual savings, where: Total Annual Savings (R$) = Annual savings – Operational cost
(4)
5.1 Treated RWH system analysis The proposed treated rainwater system has a total cost of R$21,044.56 (US$9,465.46), with an annual operating cost of R$188.26 (US$84.67) and generates an annual savings of R$2,150.80 (US$967.39). Having a total annual savings of R$1,962.54 (US$882.71), this system’s payback period is of almost 11 years. 5.2 Potable RWH system analysis The proposed potable rainwater system generates a savings of R$4,407.18 (US$1,982.26) per year, has an annual operating cost of R$748.09 (US$336.48) and needs an initial investment of R$34,336.95 (US$15,444.10). With the total annual savings of R$3,659.29 (US$1,645.88), this system has a payback period of approximately 9½years.
6
Conclusion
This study proposes two types of indirectly pumped systems: a treated RWH system and a potable RWH system. Since the site already makes use of WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
390 Eco-Architecture: Harmonisation between Architecture and Nature underground water for irrigation and other external uses like car and floor washing, such untreated uses were ruled out. The proposed treated RWH system costs R$21,044.56 (US$9,465.46), conserves 222.65m3 of water and saves R$2,150.80 (US$967.39) per annum. Considering the system’s annual operating cost of R$188.26 (US$84.67), that reduces its annual savings to R$1,962.54 (US$882.71), leads to a payback period of approximately 11 years. The proposed potable RWH system presented a lower payback period of just about 9½ years, being able to conserve 456.25m3 per year. The potable system would require a higher investment of R$34,336.95 (US$15,444.10) to install it, having an annual operational cost of R$748.09 (US$336.48). The potable RWH system conserves more water, and has a lower payback period than the treated RWH system because it harvests and uses more rainwater. Although, there is a setback, the potable system contains a much higher capital cost and operational cost, requiring a higher initial investment capital and annual expenses. Actually, both systems present a medium term payback period and perhaps it would be necessary some sort of public financing with low interest rate and long-term credit in order to convince households to invest on them. Or, what is the same, introduce a discount in the water and sewage bill for the households who have installed it.
References [1] [2] [3] [4] [5]
Fonseca, A., A ordem e economizar água, Correio Braziliense, 16 February 2005. CAESB, http://www.caesb.df.gov.br/. Gould, J. and Petersen, E., Rainwater Catchment Systems for Domestic Supply: Design, construction and implementation. London: ITDG Publishing 1999. Leggett, D., Brown, R., Brewer, D., Stanfield G. and Holliday, E., Rainwater and greywater use in buildings: Best practice guidance. London: CIRIA, 2001. Santos, G. and Poledna, S., Meio Ambiente, Reciclagem e Tratamento de Resíduos. Sistema Brasileiro de Resposta Técnica. Ministério da Ciência e Tecnologia: SENAI, 2005.
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Reliability of rainwater harvesting J. W. Male & M. S. Kennedy School of Engineering, University of Portland, USA
Abstract The increased emphasis on sustainability has resulted in an effort to reduce the reliance on municipal water in favor of the use of collected rainwater. This paper addresses the reliability of rainwater collection and use for residential buildings. It describes a procedure that utilizes a water balance based on the amount of collected rainfall, household demand, and storage tank capacity. The probabilistic nature of rainfall is incorporated by establishing weekly exponential distributions based on historical data. These rainfall distributions are used in a Monte Carlo simulation along with characteristics of the residential system (catchment area, storage tank size, household demand, etc.). Results show that along with the size of catchment area, the storage tank capacity is critical in determining the reliability of the system. The procedure is illustrated with data from Portland, Oregon. Keywords: rainwater harvesting, reliability, residential water supply.
1
Introduction
With increasing water rates, a growing number of homeowners are considering the use of rainwater to help lessen the reliance on municipal water. While the practice is more common in other countries, it is far from widespread in the U.S. In addition, water supply utilities are also looking for ways to reduce water use and forestall the need for capacity expansion. Judicious use of rainwater has the potential to address both concerns. The intent of this paper is to assess the potential use of rainwater for domestic purposes in Portland Oregon, paying particular attention to the reliability of rainwater collection. 1.1 Previous work The use of rainwater has been addressed by a number of individuals and organizations, but usually from the practical viewpoint of design. There are a WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060391
392 Eco-Architecture: Harmonisation between Architecture and Nature number of publications that emphasize overall sustainable practice with sections on rain harvesting (e.g., City of Austin [1], Barnett and Browning [2]). Others are specific to water supply (e.g., Milne [3], Pacey and Cullis [4]). Several publications are aimed specifically at developing countries, where safe distribution systems may not be in place (e.g., Fok et al. [5], Minnigh et al. [6], Schiller and Latham [7]), or where rainfall is minimal (e.g., NAS [8], Minnigh et al. [6]). Much of the published work on rain-water harvesting pertains to the practical aspects of systems, including component design, code issues, and expected water yield. The Texas Water Development Board [9] presents a stepby-step approach to estimate how much rain might be collected, along with rainfall frequency curves for several cities in the state. Few approaches have attempted to incorporate the reliability of rainfall by analyzing the variability and sequencing of rainfall on a period-to-period basis. Schiller [10] presented a method using monthly time increments and historical rainfall data. 1.2 Rainwater collection components While there are several variations, a basic rainwater collection system incorporates the following components: (1) catchment – an impervious surface that collects rain, usually a roof, (2) collection – gutters and downspouts to direct the water from the catchment area to storage, (3) first flush diverter – a device to divert the initial fraction of rainfall, (4) storage – a reservoir that stores collected rainwater for future use, (5) overflow – a means of removing excess water from the tank, (6) conveyance – a delivery pipe from the tank to the end use, and (7) treatment – a means to improve quality to meet end use requirements. The important components for this study are the catchment and storage. The size and surface characteristics of the catchment are important in determining the quantity of water entering the tank. Naturally, there is a linear relationship between the catchment area and the amount of rainwater collected. For every one inch of precipitation, roughly 2/3 of a gallon of water is collected per horizontal square foot of the catchment. However, some initial rain is lost through the wetting of the roof. In addition, for better water quality, the collection sys-tem is often designed to divert away from the tank the initial portion of the runoff (first flush). The storage tank is a critical determinant of the system reliability. A larger storage tank will allow for a longer water delivery period through dry months. 1.3 Portland’s rainfall Portland’s precipitation averages approximately 37 inches per year, with most of it falling as rain between October and June. Daily rainfall values for Portland exist for 62 years, from which weekly averages were determined, as shown in Figure 1. The resulting table of 52 values for each of 62 years was used to determine statistical parameters, appropriate distributions, and correlation coefficients.
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1.20 1.00 0.80 0.60 0.40 0.20 49
45
41
37
33
29
25
21
17
9
13
5
1
0.00 Week of the year
Figure 1:
2
Histogram of weekly average rainfall amounts for Portland Oregon.
Reliability analysis
2.1 Water balance A spreadsheet program was created to account for water inflow, outflow and storage in the system. For each of the simulations several user-defined parameters were required, including: daily demand, catchment (usually roof) size, storage tank capacity, percent-age lost to first flush, and the status of the tank (full or empty) at the start of simulations. A simple water balance, shown in Equation (1), was used to deter-mine the volume stored at the end of the current week by adding weekly rainfall to the storage carried over from the previous week, and subtracting the weekly demand. The rainfall, in inches, was selected from an appropriate statistical distribution, described later. if Si +1 < 0 0 Si +1 = Si + (1 − flush )( I i ) − Di = CAP if Si +1 > CAP S i +1 otherwise
where:
Si+1 Si flush Ii
Di CAP
(1)
= storage at end of week i, = storage at beginning of week i, = the fraction of a rainfall event diverted from storage tank, = inflow during week i 1 = ( 7.48 gal. / ft.3 )( roof size in ft.2 ) ( rainfall in inches ) , 12 = water demand during week i, and = capacity of tank.
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394 Eco-Architecture: Harmonisation between Architecture and Nature
Input • Average weekly rainfall data • Rainfall distribution function • Correlation coefficients
Monte Carlo Simulation
Simulated weekly rainfall
• • • • •
Input Roof area Storage tank volume Consumptive water demand Water losses (first flush, evaporation, etc.) Unit costs
Figure 2:
Water Balance
Output Distribution • Number of weeks that storage tank is available • Revenue losses
Diagram of the procedure.
Figure 2 shows a schematic diagram of the procedure. For each week, the spreadsheet recorded tank availability (i.e., non-zero storage at the end of the week). The water balance was conducted for 52 weeks of the year, and the total number of weeks that the tank was available for use was determined. The water balance was performed on a yearly basis, starting each new simulation with the beginning of each calendar year. This assumption corresponds to the practice of not using the tank when it is empty during the later summer and early fall months, and allowing the tank to fill during the fall. Therefore, week number one was assumed to be the first week in January, starting the water balance with a full tank. 2.2 Reliability analysis
The reliability of a rainwater collection system cannot be determined using only the weekly average rainfall. Examination of the average precipitation data for Portland indicates that when averaged over the historical record, each week of the year receives some rainfall. However, closer examination of all the data shows that in some years Portland can go several weeks during the summer months without any significant precipitation. A storage tank designed using average weekly precipitation data may not be adequate during dry summers. In order to determine the reliability of a storage tank during dry periods, the variability in rainfall must be incorporated into the water balance analysis. A stochastic component was incorporated into the analysis by defining probability distributions for each week of rainfall included in the water balance and WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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beginning of each calendar year. This assumption corresponds to the practice of not using the tank when it is empty during the later summer and early fall months, and allowing the tank to fill during the fall. Therefore, week number one was assumed to be the first week in January, starting the water balance with a full tank. 2.3 Reliability analysis
The reliability of a rainwater collection system cannot be determined using only the weekly average rainfall. Examination of the average precipitation data for Portland indicates that when averaged over the historical record, each week of the year receives some rainfall. However, closer examination of all the data shows that in some years Portland can go several weeks during the summer months without any significant precipitation. A storage tank designed using average weekly precipitation data may not be adequate during dry summers. In order to determine the reliability of a storage tank during dry periods, the variability in rainfall must be incorporated into the water balance analysis. A stochastic component was incorporated into the analysis by defining probability distributions for each week of rainfall included in the water balance and performing a Monte Carlo simulation. The simulations were performed using a proprietary software, Crystal Ball (Decisioneering [11]) which allows the designation of input probability distributions and selection of output variables. The simulation used the 52 distributions determined from the historical data, along with the week-to-week correlation coefficients. To incorporate rainfall probability distributions, each of the 52 weekly data sets was analyzed using both Chi Squared and Kolmogorov-Smirnov tests. The exponential distribution generally provided an excellent approximation of weekly rainfall frequencies.
Results of 10,000 Simulations 1,200
Frequency
1,000
Roof area = 1000 sq. ft. Storage = 500 gallons
800 600 400 200 0 1
3
5
7
9
11
13
15
17
19
21
23
25
Number of Weeks
Figure 3:
Frequency distribution for 10,000 simulations of tank availability for roof area of 1000 sq. ft. and tank size of 500 gallons.
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396 Eco-Architecture: Harmonisation between Architecture and Nature 2.4 Interpretation of simulation output
Monte Carlo simulations consisted of 10,000 iterations of the water balance, each based on 52 weeks of rainfall data generated from 52 exponential distributions. The output from these simulations is presented as a distribution representing the number of weeks in a calendar year that the storage tank is available for use. From these distributions, a reliability can be associated with the specific number of weeks that the tank is avail-able. The results of one simulation for a roof area of 1,000 ft2 and a tank size of 500 gallons are shown in Figures 3 (probability distribution) and 4 (cumulative distribution). As can be seen the results are sym-metrical, resembling a normal distribution. For a particular combination of roof area and tank size, the reliability associated with the number of weeks that water is available can be predicted. For example, there is a 90% chance that water will be available in the tank eight weeks of the year. Where as, the probability that the tank will be available 12 weeks of the year, is only 50%. At the other extreme, there is only a 10% chance that the tank will be available for 17 weeks.
Percentage of Simulations Exceeding
100%
Model Simulations
90%
10%
80%
50% 70%
90%
60% 50% 40% 30% 20% 10% 0%
0
Figure 4:
3
5
10
15
Number of Weeks
20
25
Cumulative distribution 10,000 simulations of tank availability for roof area of 1,000 sq. ft. and tank size of 500 gallons.
Results
Simulations were performed for roof sizes of 1,000, 2,000, and 3,000 sq. ft. and for tank sizes varying from 200 to 1,500 gallons. Reliability results for these combinations of roof area and storage tank volume are summarized in Figures 5, 6, and 7. Also shown in these figures is the number of weeks of available storage obtained by simply using the 62-year average rainfall for each of the 52 weeks of the year. As would be expected, for a desired reliability, as the tank size and roof size increase, the number of weeks that the tank is available for use also increases. It is interesting to note that the relationship of the “aver-age results” (those calculated from a single simulation using the 62-year average weekly values) to the reliability results, changes with different roof sizes. In particular, for the 1,000 ft2 roof, using an average value significantly WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Weeks of Available Storage
underestimates the utility of the systems for all tank sizes. For the 2,000 ft2 roof, the “average results” show relatively good agreement with the reliability predictions. With the 3,000 ft2 roof, the utility of the system is overestimated for smaller tank sizes using “average results,” but both the “average results” and reliability predictions are in agreement for larger tank sizes. Thus, not only is there an apparent disagreement between “average results” and reliability predictions, this discrepancy is a function of both roof area and storage tank volume. This seemingly anomalous result is addressed further in the discussion section.
30 10% Reliability 90% Reliability
25
50% Reliability Average
20 15 10 5 0 0 Figure 5:
4
500 1000 Tank Size, gallons
1500
Reliability results for a 1,000 sq. ft. roof area.
Discussion
4.1 Reliability
As can be seen from Figure 5, for a specified number of available weeks (a horizontal line on the figure), the reliability increases with tank size. Likewise, for increasing roof size (Figures 5, 6, and 7), the reliability increases. However, when comparing the results using average values to the median results (50% reliability), a different trend is apparent. The effect of the difference is most dramatically seen in Figure 7, where for a small tank (200 gallons), the calculation using weekly average rainfall amounts yields an available supply for 34 weeks, whereas the median simulation result yields only 26 weeks. In contrast, for a large tank, the two approaches yield about the same result. One can draw the conclusion that, for Portland’s rainfall data, the average and median results are not significantly different for large roofs and large tanks, but they are for small tanks. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
398 Eco-Architecture: Harmonisation between Architecture and Nature 45 10% Reliability 50% Reliability 90% Reliability Average
40
Number of Weeks
35 30 25 20 15 10 0
200
400
600
800
1000
1200
1400
1600
Tank Size, gallons
Figure 6:
Reliability results for a 2,000 sq. ft. roof area. Roof Size = 3000 sq. ft.
50 10% Reliability 50% Reliability
# Weeks Available
45
90% Reliability Average
40 35 30 25 20 15 0
200
400
600
800
1000
1200
1400
Tank Size, gallons
Figure 7:
Reliability results for a 3,000 sq. ft. roof area.
These results can be explained by the fact that the mean value for the heavily skewed exponential distribution of precipitation values is higher than the median value. While it is true that the median value is not used as an input value (as the mean is), many more of the input values that are selected from the input distribution tend to be closer to the lower, median value. During the dry summer WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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months when rainfall is low, mean values do not represent a likely sequence of low rainfall; a sequence of values quite likely at, or close to zero. For a small tank, the mean values (larger relative to the values close to the median) have a more pronounced effect on filling a tank, particularly a small tank. For example, for week 25, which leads into the dryer summer weeks, the average weekly rainfall of 0.4 inches will fill a 500-gallon tank to almost 85% of its capacity. The median value only provides only about 59% of the tank capacity. Note that for each of these calculations, 15% is subtracted for first flush. 4.2 Water savings
The simulation procedure is likely to underestimate the amount of water that can be utilized by a rain harvesting system. Because the computational routine is set up with weekly increments, the maximum amount of water that can be provided on a weekly basis is equal to the capacity of the tank. In reality, even though it may not rain continuously and water may not be used continuously, the tank is not emptied and filled only once a week, as is done in the routine. Therefore, depending on rainfall and demand, the amount of water available for use over a week’s time could exceed the tank volume. For example, for a 1,000-gallon tank, the procedure can utilize at most 1,000 gallons a week. Yet if the problem is addressed on a daily basis, it is theoretically conceivable that the tank could refill every day, allowing the use of up to 7,000 gallons a week. This scenario assumes a 3,000 sq. ft. roof and 0.8 inches of rainfall a day, seven days in a row. This rainfall is higher than normal for Portland. However, when picking a rainier-than-average week (week 48) and the median value from that week (1966), the daily rainfall values of 0.03, 0.04, trace, 0.19, 0.27, 0.21, and 0.18 inches yield a usable volume of over 1,350 gallons, higher than the 1,000 gallons the procedure would have determined. This calculation assumes the first three daily values never reach the tank and the others are reduced by the first flush amount of 15 percent. There are many weeks during the historical record that have far greater weekly rainfalls. The continuous-use scenario assumes that the user takes advantage of the system daily; for example it is connected permanently to the household supply, allowing use of the municipal water if the tank goes dry during a day. A procedure using daily time increments is an area for further research.
5 Summary and conclusions This study assessed the reliability of residential rainwater harvesting systems to supply water for different catchment areas and storage volumes. In particular, the procedure determines the number of weeks that such a system is available to supply a given demand. Results of the approach show that for rainfall patterns similar to those seen in Portland Oregon, combinations of roof/tank sizes from 1,000 sq. ft./500 gallons to 3,000 sq. ft./1,500 gallons have a 50% probability of reducing annual municipal water use by 8,000 to 27,000 gallons, respectively, for each system installed. Several conclusions can be drawn from the study: WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
400 Eco-Architecture: Harmonisation between Architecture and Nature • • •
Median (50% reliability) storage availability can not be predicted based on average weekly rainfall data, Reliability analysis gives a more complete picture of the effects of roof area and storage tank size on performance of rainwater harvesting systems, and Rainwater harvesting can reduce water use.
Acknowledgements The authors would like to thank the Portland Water Bureau for providing support for the project. They would also like to thank Jim Doane and Marie DelToro of the Water Bureau for their valuable contributions. At the University of Portland, four students contributed to the project: Robb Lukes, Lara Karamatsu, Ashley Cantlon, Brendan O’Sullivan, and David Shunk.
References [1] [2] [3] [4] [5]
[6]
[7] [8] [9] [10] [11]
City of Austin, Sustainable Building Sourcebook, City of Austin Environmental and Conservation Services Department, Austin, TX, 1995. Barnett, D.L. and W.D. Browning, A Primer on Sustainable Building, Rocky Mountain Institute, Snowmass, CO, 1995. Milne, M., Residential Water Re-Use, Water Resources Center, Davis CA, 1979. Pacey, A. and A. Cullis, Rainwater Harvesting: The Collection of Rainfall and Runoff in Rural Areas, Intermediate Technology Publications. London, 1986. Fok, Y.S., E.T. Murabayashi, and R.H.L. Fong, “Rainwater RoofCatchment Cistern Systems for Residential Water Supply,” Third World Congress on Water Resources Proceedings, Vol. IV, International Water Resources Association, Mexico City, 23-27 April, 1979. Minnigh, H., H. Mark, M. Diaz, and J. Meyers, SWAP for Rainwater: Experience in the U.S. Virgin Islands, presented at American Water Resources Association 2003 International Congress, 29 June – 2 July, 2003. Schiller, E. J., and B. G. Latham, A Generalized Method for Designing Rainwater Collectors, Canadian Water Resources Journal, Vol. 17, No. 2, 1992. NAS, More Water for Arid Lands, National Academy of Sciences, Washington DC, 1974. Texas Water Development Board, Texas Guide to Rainwater Harvesting, Austin TX, 1997. www.twdb.state.tx.us/publications/reports/RainHarv.pdf Schiller, E. J., Rooftop Rainwater Catchment Systems for Drinking Water Supply, Water Supply and Sanitation in Developing Countries, Ann Arbor Science, 1982. Decisioneering, Inc. Crystal Ball: Forecasting and Risk Analysis for Spreadsheet Users. CG Press: Broomfield, Colorado, 1996.
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User experiences with decentralised water systems in an ecological residential area A. A. E. Luising Delft University of Technology, Faculty of Architecture, Environmental Design, The Netherlands
Abstract EVA-Lanxmeer is an ecological residential area in the centre of The Netherlands. An integrated (waste) water concept was an essential part of the design. On the incoming side two water streams are distinguished: drinking water and household water. On the outgoing side the household wastewater is divided into two streams: black water and grey water. This paper discusses the attitude of the users on water saving and water treatment systems. The central theme is the relation between the physical implementation of the water systems in the design and the use of it by the inhabitants of the area. For this research interviews were held with the inhabitants of the project. The water concept was an important part of the concept of the project and it added to the visible quality of the area. Furthermore, the people considered the systems very reliable even if the systems had not yet been put into practice. Keywords: grey water, black water, wastewater, decentralised sanitation, user experiences, ecological residential area.
1
Introduction
Central end of pipe wastewater management causes various environmental and social problems. Integrated water management can offer an opportunity for residential areas to improve building and living quality. Centralised wastewater concepts are not sustainable: they use water for flushing, need for infrastructure, loss of valuable nutrients in the wastewater and a lack of user consciousness. Decentralised wastewater concepts can be a solution for these problems. The change from central to decentralised systems means that wastewater systems come closer or even in the built environment. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line) doi:10.2495/ARC060401
402 Eco-Architecture: Harmonisation between Architecture and Nature This causes a new view on the subject. How are these systems to be integrated in the built environment? Which new challenges are to be met? What function do these systems have except for cleaning wastewater. How have they to be used and maintained. This paper describes a research about the implementation of decentralized systems and user aspects. Lanxmeer, an ecological area in Culemborg, was used as a case study. In this area an integrated water system was part of the design. Some parts of the system were functioning at the time of the research; some parts just existed on drawings. Goal of the research was to find relations between user aspects and the physical implementation of the system. For a successful application of a decentralized system a good technical design is essential. But after building the system the user and maintenance phase are just as important for success. Aspects as trust, responsibility, information, physical appearance and location play an important role. 1.1 Location EVA-Lanxmeer is located in Culemborg in the centre of the Netherlands. The project is realized in cooperation with future inhabitants. Goal was to create an integrated design in which sustainable development and a high quality of the living environment played a central role. The houses and buildings lay horseshoe shaped round a water collection area and consist of three neighbourhoods, fig. 1. The area is characterised by a spacious and green lay-out. The program consists of two hundred houses, office space, a city farm and a multifunctional congress and educational centre. Except for attention for renewable materials and an energy neutral concept an integrated water system was implemented [1, 2].
Figure 1:
Location of Lanxmeer.
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Figure 2:
403
Water made visible in Lanxmeer: open rain water gutters.
1.2 Process and organisation Lanxmeer was founded in 1996 by a project team formed by the municipality of Culemborg and the EVA-Foundation. In 1998 the inhabitant’s organisation BEL was founded. It looks after the interests of the inhabitants. It consists of various working groups, for example traffic, gardens and car sharing. The project office is responsible for the organisation of the building project and informs the inhabitants of Lanxmeer about the progress. 1.3 Water system The plan location in the middle of a water collection area was the basic principle for the urban design. The water systems take a very prominent role in the area. The water systems take considerable space on prominent positions. Water is visible everywhere in Lanxmeer, fig. 2. Because the area is situated in a water collection area this made special demands on the building manner related to the water system. At the same time this offered opportunities to show many aspects of sustainable water management. The houses are built on a foam concrete foundation in stead of building on piles to prevent contact between drinking water layers in the soil with contaminated water layers. The water collection area is protected from dirty water inlet by creating a constant overpressure in the area. The wastewater flows away from the water collection area.
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Figure 3:
Reed bed filter.
Figure 4:
Rainwater pond.
collecting
The basic principle was to save and reuse as much water as possible and protect the vulnerable water collection area. Every of the three neighbourhoods have their own water system for grey, black (toilet water) and rainwater. Rainwater is collected in retention ponds situated around the water collection area, fig. 4. The grey water is treated in one of the three reed bed filters, fig. 3. The effluent infiltrates in wadi’s. These wadi’s are used as well to infiltrate a part of the rainwater. The retention ponds for collecting the rainwater are situated around the water collecting area. The black water is collected from the whole area and in the future it will be treated in a biogas treatment plant. At this moment it flows to the sewer which was added as a back up system in the design. Part of the plan is a multifunctional conference and education centre. The wastewater of this centre will be treated separately in a Living Machine.
2
Methods
In order to investigate the relation between implementation and the user aspects of the water systems, a research frame was set up. Firstly the water systems in the area were studied. This included the technical specifications, the implementation in the design of the area and the process from design to implementation and use of the water systems. Inhabitants of the area where interviewed about their attitude to decentralised water systems and their experiences so far. A list of questions was set up using key themes from the system analysis and former inhabitant research. 102 letters were sent to all the inhabitants of EVA-Lanxmeer. Fifteen in depth interviews were held. Because of the small number of interviews the results are just interpreted qualitatively. The interviews consisted of five parts: • Common questions about the residential area • Decision-making, participation and process: the commitment and opinion of the respondents regarding the water system was checked • The wastewater treatment system: knowledge and point of view was tested. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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• Maintenance • Application: these questions go in to the practical use of the systems and final products.
Figure 5:
3
Wastewater systems in Lanxmeer, picture Paul de Graaf.
Results and discussion
3.1 Trust Most respondents trusted the project office to take the right decisions regarding the water system. When they were asked if any health risks were involved with the system, nobody expected any problems. They even planned to use the future compost of the anaerobic digester in the communal gardens. Although many of WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
406 Eco-Architecture: Harmonisation between Architecture and Nature the respondents were not satisfied with the information they received during the process, this did not lead to a decreased level of trust in the water system itself. For a functioning grey water system it is important that users do not contaminate the reed beds by disposing toxic materials in the kitchen sink. For example no chlorine or remains of paint can be disposed. There was some distrust between inhabitants; they were afraid that others would not treat the grey water system with care. The residents are responsible for the water system together and therefore dependant on each other’s behaviour. 3.2 Information Inhabitants are informed about the water system by the project office of Lanxmeer. Information about the household water is the responsibility of the supplier of the household water. Respondents wanted to be informed about the water systems by meetings and mail. During the interviews it was not clear if the household water network would be brought into use. The information provision by the supplier of the water was considered poor. None of the respondents was informed about this process. Due to a governmental regulation it was prohibited to use household water in houses. 3.3 Identity There seems to be a separation between inhabitants of the various neighbourhoods. The difference between owner-occupied houses and rented houses is not clearly present although some house-owners show their concern about tenants not visiting information meetings. This could cause problems when they have to be informed about using the water system. Inhabitants who not considered themselves as environmental friendly were influenced by their neighbours; good examples were taken over. In general the respondents believed that the water system is an integrated part of Lanxmeer. In spite of the fact that a considerable part of the system was not yet brought into use (no household water and black water system) they would be very disappointed if this was not going to happen. The water system is considered as one of the essential projects in the area. The area would have failed if the decentralized water system would not be completed according to most of the respondents. Previous research [3, 4] showed that most of the inhabitants moved to Lanxmeer because of the ecologically sound character. Besides, the water system has important social control function. The sensitivity from the grey water system means that users have to treat it with care. If the grey water system would not be put into use there would be no necessity to use ecologically sound products and with it the solidarity would decrease 3.4 Location of the water system At the time of the interview the grey water system was constructed. The motives of the designers to locate the system on a certain place diverged. WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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The location involved accessibility, safety and educational reasons. One the one hand the water system is an important visiting card of the area. For this reason it should be visible to as many people as possible. For example places on the border along a busy cycle track where many people pass on their way to the Station, fig. 6. On the other hand the water system is vulnerable and the system could be better situated in a sheltered place.
Figure 6:
Information board reed bed filter along cycling track.
3.5 Maintenance Most respondents do not want to be involved in the maintenance of the water system. It takes too much time and many of them already are a member of other teams. Some of the respondents doubt if they have enough knowledge of the water system. 3.6 Scale The level of social cohesion is highest on the smallest level of scale in Lanxmeer: the courts. Inhabitants are responsible together for the system, use and maintenance. Therefore the optimum level of scale for the water system would be the court level, fig. 7. This would involve the users more in the system, although respondents indicated that they did not consider themselves qualified for maintenance tasks. Furthermore the infrastructure can be more efficient. The recycled water could be used in de court as well. 3.7 Selection of water system Saving water is the main motive for inhabitants to have a decentralised water system. Saving costs is not an issue. Respondents expect that using a decentralised water system will improve the (environmental) quality of their living environment. In selecting a water treatment system a number of aspects are of concern for inhabitants. To what extent the system can be integrated in WIT Transactions on The Built Environment, Vol 86, © 2006 WIT Press www.witpress.com, ISSN 1743-3509 (on-line)
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Figure 7:
Communal garden in court.
the situation is of importance. Respondents choose for a system that merges in its surroundings. A helophyte filter is a good example of a merging system because the plant fit well in the green design. However, because Lanxmeer aims to be a model for a sustainable area in which sustainable techniques are shown, systems are made visible in the area. Rainwater flow through open gutters to the retention ponds and in de future educational centre a Living Machine is planned.
References [1] [2] [3] [4]
Website inhabitants EVA-Lanxmeer (BEL), www.bel-lanxmeer.nl. Website EVA-Lanxmeer Foundation, www. eva-lanxmeer.nl. V&L Consultants, Bewonerservaringen EVALanxmeer te Culemborg, Rotterdam, 2003. Ger de Vries, Bewoners in EVA-Lanxmeer. Dik tevreden, Magazine Puur Bouwen, nr. 5, 2004.
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Author Index Anselm A. J. ............................ 195 Armpriest D. ............................ 133 Baker N........................................ 3 Bojórquez-Morales G. ............. 205 Bosman G. ............................... 297 Brebbia C. A. ........................... 215 Bt Omar D. ................................ 83 Chen C.-J. .................................. 73 Connors K................................ 287 Corona-Zambrano E. ............... 205 Costanzo E............................... 361 Drei A. ..................................... 369
MacBurnie I............................... 63 Male J. W................................. 391 Marletta L. ....................... 267, 319 McCabe C................................ 237 Metallinou V. A......................... 15 Ochoa-Corrales J. .................... 205 Ott B. ......................................... 45 Quale J. ...................................... 53 Richarde R. .............................. 195 Robertson S. ............................ 351 Rojas-Caldelas R. .................... 205 Rosenhouse G. ......................... 331 Rossi P. .................................... 247
Evola G. ........................... 267, 319 Garrison M............................... 155 Gorst J...................................... 215 Haglund B................................ 133 Harwood P. .............................. 103 Ibrahim R................................. 185 Kennedy M. S. ......................... 391 Kilby P..................................... 115 Kirschner U.............................. 143 Koester R. J.............................. 175 Kytzia S. .................................. 227 Lawton M. ............................... 341 Luising A. A. E........................ 401 Luna-León A............................ 205 Lützelschwab I......................... 227
Sala N. ..................................... 163 Sant’Ana D. ............................. 381 Scudo G. .................................. 369 Seyler C. .................................. 227 Sicurella F........................ 267, 319 Soria López F. J. ........................ 23 Stevenson F. ............................ 257 Stoy C. ..................................... 227 Straka V. .................................. 277 Swensen G. .............................. 123 Thompson M. .......................... 351 Tsianaka E. ................................ 93 van Hal A................................... 35 van Timmeren A...................... 309
Flow Phenomena in Nature
Design and Nature III
A Challenge to Engineering Design
Comparing Design in Nature with Science and Engineering
Edited by: R. LIEBE, SIEMENS Power Generation, Germany
Edited by: C. A. BREBBIA, Wessex Institute of Technology, UK
Do we have an adequate understanding of fluid dynamics phenomena in nature and evolution, and what physical models do we need? What can we learn from nature to stimulate innovations in thinking as well as in engineering applications? Concentrating on flight and propulsion, this unique and accessible book compares fluid dynamics solutions in nature with those in engineering. The respected international contributors present up-to-date research in an easy to understand manner, giving common viewpoints from fields such as zoology, engineering, biology, fluid mechanics and physics. This transdisciplinary approach eliminates barriers and opens wider perspectives to both of the challenging questions above. Contents: Introduction to Fluid Dynamics; Swimming and Flying in Nature; Generation of Forces in Fluids - Current Understanding; The Finite, Natural Vortex in Steady and Unsteady Fluid Dynamics - New Modelling; Applications in Engineering with Inspirations From Nature; Modern Experimental and Numerical Methods in Fluid Dynamics. ISBN: 1-84564-001-2 2006 apx 800pp apx £195.00/US$312.00/€292.50
Throughout history, many leading thinkers have been inspired by the parallels between nature and human design, in mathematics, engineering and other areas. This book brings together articles from researchers from around the world working on a variety of studies involving nature and their significance for modern scientific thought and design. Featuring papers from the Third International Conference Comparing Design in Nature with Science and Engineering, the text will be of interest to researchers and those interested in the study of natural materials, organisms, processes and their significance for design in the world today. Notable topics include: Design in Nature; Shape and Form in Engineering and Nature; Nature and Architectural Design; Thermodynamics in Nature; Biomimetics; Natural Materials in Engineering; Mechanics in Nature; Bioengineering; Bionics; Solutions from Nature; Evolutionary Optimization; Complexity; Sustainability Studies. ISBN: 1-84564-166-3 2006 368pp apx £145.00/US$265.00/€217.50
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Compliant Structures in Nature and Engineering Edited by: C. H. M. JENKINS, Montana State University, USA Nature is the grand designer and human engineers have taken great motivation from it since the earliest of times. This book celebrates structural compliance in nature and human technology. Examples of compliant structures in nature abound, from the walls of the smallest cell, to the wings of the condor, to the tail of the gray whale. The subject of compliant structures in nature and engineering is timely and important, albeit quite broad and challenging. A concise summary of the important features of these interesting structures, this volume demonstrates, wherever possible, a mapping between naturally compliant structures and the promise and opportunity commensurate in human engineering. Series: Design and Nature Vol 5 ISBN: 1-85312-941-0 2005 296pp £97.00/US$175.00/€145.50
WIT eLibrary Home of the Transactions of the Wessex Institute, the WIT electronic-library provides the international scientific community with immediate and permanent access to individual papers presented at WIT conferences. Visitors to the WIT eLibrary can freely browse and search abstracts of all papers in the collection before progressing to download their full text. Visit the WIT eLibrary at http://library.witpress.com
Nature and Design Editors: M.W. COLLINS, London South Bank University, UK, M.A. ATHERTON, London South Bank University, UK and J.A. BRYANT, University of Exeter, UK Combining authority, inspiration and stateof-the-art knowledge, this volume provides a comprehensive study of the fundamental laws of nature and design. Partial Contents: Optical Reflectors and Antireflectors in Animals; Adaptive Growth; Robustness and Complexity; A Medical Engineering Project in the Field of Cardiac Assistance; Creativity and Nature; Design in Plants; The Tree as an Engineering Structure. Series: Design & Nature, Vol 1 ISBN: 1-85312-852-X 2005 360pp £133.00/US$213.00/€199.50
Design and Nature Comparing Design in Nature with Science and Engineering Editors: C.A. BREBBIA and L.J. SUCHAROV, Wessex Institute of Technology, UK and P. PASCOLO, Università degli Studi di Udine, Italy Providing researchers in this subject with fresh impetus and inspiration, this book consists of papers presented at the first international conference on this subject. The contributions reflect the rich variety of work taking place and cover topics within shape and form in engineering and nature, solutions from nature, design and sustainability studies, nature and architectural design, mechanics and thermodynamics in nature, biomimetics and materials, and vision in science and nature. Series: Design & Nature, Vol 3 ISBN: 1-85312-901-1 2002 460pp £149.00/US$223.00/€223.50
Optimisation Mechanics in Design and Nature II Nature Comparing Design in Nature with Editors: M.W. COLLINS, D.G. HUNT and M.A. ATHERTON, London South Bank University, UK
This book comprises a study of the two great organic solids in Nature, namely wood and bone. The common scientific laws which act in parallel for both natural and manmade materials are detailed as wood and bone are studied in their natural structural environment as well as in the fields of engineering structural analysis and medical analysis. The relationship between them enables wood to be used in engineering structures and man-made materials to be used as scaffolding for tissue restoration in the human environment. The ‘two-way traffic’ relationship explored in this volume is termed biomimesis, a modern development of the ancient Greek concept of mimesis - the man-made imitation of nature. Contents: Preface; Wood as an Engineering Material; Uniform Stress - A Design Rule For Biological Load Carriers; Nature and Shipbuilding; The Structural Efficiency of Trees; Application of the Homeostasis Principle to Expand Gaudí’s Funicular Technique; Bones - The Need For Intrinsic Material and Architectural Design; Restoration of Biological and Mechanical Function in Orthopaedics - A Role For Biomimesis in Tissue Engineering; Design in Nature. Series: Design & Nature, Vol 4 ISBN: 1-85312-946-1 2004 176pp £70.00/US$112.00/€105.00
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Science and Engineering Editors: M.W. COLLINS, London South Bank University, UK and C.A. BREBBIA, Wessex Institute of Technology, UK Containing the proceedings of the Second International Conference on Design and Nature, this book brings together contributions from researchers working around the world on a variety of studies involving nature and its significance for modern scientific thought and design. Over 55 papers are featured and these span the following broad range of topics: Architectural Design and Structures; Architecture and Sustainability; Acoustics; Biology; Biomimetics; Design Philosophy and Methods; Human Biology and Medicine; Materials; Nature and Architectural Design; Space. WIT Transactions on Ecology and the Environment, Volume 73 ISBN: 1-85312-721-3 2004 648pp £186.00/US$298.00/€279.00 All prices correct at time of going to press but subject to change. WIT Press books are available through your bookseller or direct from the publisher. WIT Press is a major publisher of engineering research. The company prides itself on producing books by leading researchers and scientists at the cutting edge of their specialities, thus enabling readers to remain at the forefront of scientific developments. Our list presently includes monographs, edited volumes, books on disk, and software in areas such as: Acoustics, Advanced Computing, Architecture and Structures, Biomedicine, Boundary Elements, Earthquake Engineering, Environmental Engineering, Fluid Mechanics, Fracture Mechanics, Heat Transfer, Marine and Offshore Engineering and Transport Engineering.