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Energy efficiency policy is expected to play a key role for meeting the European Union's energy targets (particularly for reduced energy demand and reduced CO2emissions) using a range of policy instrument combinations. However, most analyses undertaken so far have focused on single-policy measures rather than developing a more generic framework for assessing to what extent a particular policy mix is effective and under which specific conditions. This paper both contributes to the theoretical literature on policy mixes and undertakes an empirical analysis of the current policy mixes in buildings efficiency policy in 14 European Union countries. Building on the existing literature, and using expert knowledge, an assessment of the interaction of 55 pairs of policies is presented. This identifies policy mixes likely to deliver more, less or the same energy savings in combination than singly. The theoretical assessment is compared with actual policy mixes present within the European Union, highlighting that combinations of multiple financial incentives may need further investigation. By bringing these forms of knowledge together, the paper suggests how buildings policy mixes could be made more effective, shows gaps in current knowledge and highlights key research needs. [ABSTRACT FROM PUBLISHER]

Thermal renovation (retrofit) of residential buildings is one of the major issues in the transition to a low-carbon energy system. This paper argues that the specific conditions in shrinking middle-size cities create an especially difficult environment for energy renovations. Using empirical data from the shrinking City of Delitzsch, Germany, it is hypothesized that buildings with poor energy efficiency are often inhabited by tenants or owners who impede retrofit activities due to their socio-economic conditions. The research analyzes the relation between buildings with a high potential for final energy reduction and a concentration of low-income, older or empty-nest households. The analysis examines this relation not only on an aggregated city level but also on the level of the city's districts to identify renovation ‘hot spots’ in the city. Specific challenges are identified for building renovations in shrinking cities due to a high concentration of possible barriers in the relevant housing stock. As a further consequence, those households with a low net-equivalent income are also at risk of energy poverty. In order to achieve a low-carbon and just society, possible actions are suggested for buildings with elevated barriers to energy renovation in shrinking cities. [ABSTRACT FROM AUTHOR]

Improving the environmental performance of non-domestic buildings is a complex and ‘wicked’ problem due to conflicting interests and incentives. This is particularly challenging in tenanted spaces, where landlord and tenant interactions are regulated through leases that traditionally ignore environmental considerations. ‘Green leasing’ is conceptualized as a form of ‘middle-out’ inter-organizational environmental governance that operates between organizations, alongside other drivers. This paper investigates how leases are evolving to become ‘greener’ in the UK and Australia, providing evidence from five varied sources on: (1) UK office and retail leases, (2) UK retail sector energy management, (3) a major UK retailer case study; (4) office leasing in Sydney, and (5) expert interviews on Australian retail leases. With some exceptions, the evidence reveals an increasing trend towards green leases in prime offices in both countries, but not in retail or sub-prime offices. Generally introduced by landlords, adopted green leases contain a variety of ambitions and levels of enforcement. As an evolving form of private–private environmental governance, green leases form a valuable framework for further tenant–landlord cooperation within properties and across portfolios. This increased cohesion could create new opportunities for polycentric governance, particularly at the interface of cities and the property industry. [ABSTRACT FROM PUBLISHER]

A need exists for robust environmental and health-related information to support decisions about construction products and the design of new construction and refurbishment projects. This need arises in order to protect resources and the natural environment. The relevant information can be provided from, for example, a life cycle assessment in the form of impact indicators. However, the large, complex data can overburden individual actors in construction and property (real estate). Hence, the question arises as to whether and how the complexity of communicating environmental information for construction products can be simplified. This paper explores various approaches to grouping the different impact indicators and to determining proxy indicators and impact indices as single scores within these indicator groups. No appropriate single proxy indicator is appropriate for all impact indicators. However, a cluster of indicators can be formed and proxy indicators or impact indices can be determined within these groups. An application of the approaches to the impact indicators according to the currently discussed product environmental footprint approach is presented. With a series of single scores, an existing multi-criteria decision problem can be reduced and a basis for business-to-consumer communication can be formed. [ABSTRACT FROM AUTHOR]

This paper is a personal response to the Green Building Challenge '98 conference, held in Vancouver in September 1998. It represents an attempt to link together conceptually - and then comment on critically - the two main challenges thrown down at the conference. These were offered at the start and end by Rees and Kohler and were, respectively: (1) that developed countries reduce the environmental impact of their built environment tenfold by 2040 (Rees, 1999: p. 216), and (2) that they stop constructing additional new buildings, limiting themselves instead to improving their existing stock (Kohler, 1999: p. 317). Although not mentioned by Rees or Kohler, both of these challenges could be tackled, for example, through adopting a Service Economy approach to improving the built environment in industrialized countries. This could allow room - in terms of both resources input and pollution output - for the rapid urbanization predicted (and already occurring) in developing countries over the next 30 or 40 years. This paper seeks to locate their challenges in the context of broader initiatives to 'dematerialize' industrial economies. This is done in order to question whether the development of methods for assessing building performance should continue to address the relatively narrow resource-efficiency agenda that has predominated over the past ten years or whether it should now be extended to begin to tackle a wider remit - the sustainability of the built environment. Cet article est une reponse personnelle a la conference Green Building Challenge '98 qui s'est tenue a Vancouver en septembre 1998. C'est une tentative d'etablir un lien sur le plan conceptuel entre les deux principaux defis presentes a cette conference puis d'en faire une analyse critique. Ces deux defis ont ete exposes au debut et a la fin de la conference par Rees et Kohler et s'enoncaient comme suit: (1) d'ici 2040, les pays developpes doivent reduire, par un facteur de dix, l'impact du cadre bati sur l'environnement (Rees, 1999: p. 216); et (2) les pays developpes doivent arreter la construction de batiments nouveaux et se limiter a l'amelioration du parc immobilier existant (Kohler, 1999: p. 317). Bien que Rees et Kohler ne le mentionnent pas, ces deux defis pourraient etre releves, par exemple, par l'adoption d'une approche d'economie de services qui ameliorerait le cadre bati dans les pays industrialises. Cette nouvelle methode laisserait la place, en termes de recettes de ressources et de pollution en resultant, a l'urbanisation rapide prevue (qui se produit deja) dans les pays en developpement au cours des trente ou quarante prochaines annees. Cet article cherche a placer ces defis dans le contexte d'initiatives plus larges visant a 'dematerialiser' les economies industrielles. Il s'agit en effet de s'interroger sur le fait de savoir si l'elaboration de methodes d'evaluation des performances des batiments devrait continuer a prendre en compte la question relativement etroite du rapport entre les ressources et l'efficacite qui a predomine au cours des dix dernieres annees ou de savoir si elles devraient desormais etre etendues a la question plus large de la durabilite du cadre bati. [ABSTRACT FROM AUTHOR]

The intentions for, and the thinking behind, the Green Building Challenge (GBC) assessment framework and its development are made explicit. This paper disentangles three separate roles for environmental assessment of buildings (stimulating owners to improve a building's performance, informing decision makers during the design stages and delivering objective measurements of a building's impact on natural systems). The author provides a number of significant lessons from the development exercise and discusses further implications and directions for developing environmental assessment methods for buildings. A distinction is made between 'green' and 'sustainable' agendas and their implications for the future development of building environmental assessment methods. This is essential in order to clarify the many roles and applications demanded of these tools. The considerable practical overlap between the 'green' and 'sustainable' agendas suggests that they can be reconciled within a single tool. 'Green' performance is most usefully described in relative terms in comparison to similar buildings in the region, while absolute energy and mass flows are a prerequisite for assessing progress towards sustainability. A fewer number of carefully elected performance measures are required to provide a measure of a building's role in ecological sustainability than to describe its green performance. The GBC process has clarified the roles and applications demanded of different tools and these lessons will be integrated into the restructuring and application of GBTool , and add significantly to the wider debate on environmental assessment. Cet article explique les objectifs et les raisons qui ont amene a elaborer le cadre d'evaluation Green Building Challenge (GBC) ainsi que son evolution. Il precise le role de trois facteurs distincts qui participent a l'evaluation environnementale des batiments: inciter les proprietaires a ameliorer les performances des batiments, informer les decideurs pendant la conception et fournir des mesures objectives de l'incidence d'un batiment sur les systemes naturels. L'auteur tire un certain nombre d'enseignements significatifs de cet exercice et examine d'autres implications ainsi que des orientations relatives a l'elaboration d'autres methodes d'evaluation environnementale des batiments. Il fait la distinction entre les aspects 'verts' et les aspects 'durables' et examine leurs implications dans la perspective de l'elaboration de nouvelles methodes. Cela est essentiel si l'on veut expliciter les nombreux roles et applications demandes a ces outils. Cette distinction est capitale; le chavauchement considerable de ces aspects suggere que l'on pourrait les fusionner dans un seul outil. Les performances 'vertes' sont tres bien decrites en termes relatifs, par comparaison a des batiments similaires de la region, alors que l'energie absolue et les flux de masses sont une condition prealable a l'evaluation du progres vers la durabilite. Un nombre moins important de mesures de performances selectionnees avec soin servira a donner la mesure du role des batiments dans un contexte de durabilite ecologique plutot que de decrire leurs performances 'vertes'. Le processus GBC a precise les roles et les applications des differents outils et ces enseignements serent integres dans la restructuration du GBTool, de ses applications a une plus grande echelle et au debat elargi sur l'evaluation environnementale. [ABSTRACT FROM AUTHOR]

The resilience and capacity of historic buildings to adapt plays a vital role in mitigating climate change through adaptive reuse. The adaptive reuse of buildings is a practical substitute to demolition and has substantial economic, environmental and social benefits. However, tensions exist between the retention of heritage buildings and conformance with regulatory requirements (e.g.energy efficiency to reduce greenhouse gas emissions, disability access, etc.). This raises questions about whether regulatory systems can embrace both green building technologies and heritage conservation principles. This paper examines the challenges/barriers to successful adaptive reuse projects in Australia using a qualitative approach that involves multiple case studies and in-depth interviews with industry experts coupled with field observation and building plan appraisals. The findings show that compliance to codes/regulations and current design requirements are the major challenges encountered in undertaking adaptive reuse projects. The underlying parameters of the identified challenges will serve as an initiative for formulating prospective regulations that address changing building use, encourage the integration of modern technologies and inhibit unnecessary building demolition for future global climate protection. [ABSTRACT FROM PUBLISHER]

This paper seeks to challenge the traditional way in which we assess the value of green buildings in terms of their environmental friendliness, energy efficiency and whole life cost. In the UK, quantity surveyors (or cost consultants) have a perception that more energy efficient and environmentally friendly buildings cost between 5% and 15% more to build from the outset. This common assumption is not backed up by recent research and should be questioned. Construction professionals need to be informed of the whole life cost and environmental impact of buildings so that they can encourage key stakeholders to make more sustainable choices. These emerging issues together with practical tools are considered with case studies from recent projects. Le présent document vise à remettre en question la méthode traditionnellement utilisée pour évaluer la valeur des bâtiments écologiques en termes de respect de l'environnement, de rendement énergétique et de coût global. Au Royaume-Uni, les métreurs (ou les conseillers en coût) pensent que des constructions plus rentables sur le plan énergétique et plus respectueuses de l'environnement engendrent un surcoût global de construction compris entre 5 et 15% du coût initial. Cette hypothèse courante n'est pas étayée par les récentes recherches et devrait être remise en question. Les professionnels de la construction doivent être informés du coût global des bâtiments et de leur impact sur l'environnement, afin d'être en mesure d'encourager les principaux partenaires à effectuer des choix plus durables. Les cas d'etude issus de projets récents examinent ces nouveaux problèmes et les outils pratiques disponibles. [ABSTRACT FROM AUTHOR]

The construction and property sector has seen the development of a number of methods for evaluating the 'greenness' of buildings in the 1990s - both for new designs and existing buildings. These range from very detailed life cycle assessment methods, which account for all the embodied and operational environmental impacts of building materials, to higher level environmental impact assessment methods, which evaluate the broader implications of the building's impact on the environment. In between these two are environmental assessment methods such as BREEAM, BEPAC, LEED, and GBA. In this paper, we discuss the potential market applications of these systems and compare and contrast several of the major environmental assessment methods. Le secteur de la construction et de l'immobilier a ete le temoin du developpement d'un certain nombre de methodes permettant d'evaluer les performances ecologiques des batiments dans les annees 1990, tant sur le plan des nouveaux concepts que des batiments existants. Ces methodes vont de l'evaluation tres detailee du cycle de vie, qui tient compte de l'impact specifique et des incidences operationnelles des materiaux de construction sur l'environnement, jusqu'a une evaluation de l'impact environnemental a un niveau plus eleve. Entre ces deux extremes, on trouve des methodes d'evaluation environnementale telles que BREEAM, BEPAC, LEED et GBA. Dans cet article, nous examinons les applications commerciales potentielles des ces systemes; nous comparons, en les opposant, plusieurs methodes majeures d'evaluation environnementale. [ABSTRACT FROM AUTHOR]

The Green Building Challenge '98 (GBC '98) developed and tested an international assessment system for buildings. An underlying premise of GBC '98 was to allow for regional differences by providing flexibility and weighting of building assessment criteria within an international framework. This was considered crucial for the acceptability of the assessment system as well as for its ability to accurately reflect best local practice. Regional adaptation is complex, however, and raises many considerations that may be in conflict. This paper analyses the importance of integrating regional aspects into assessment tools on the one hand and the benefit of setting up an international assessment system on the other. An approach for achieving a balance between the regional and international levels of a universal assessment system is discussed. Issues and proposed solutions for further consideration are raised along with suggested topics for further research. Le projet Green Building Challenge '98 (GBC '98) a elabore et teste un systeme international d'evaluation des batiments. L'une des conditions sous-jacentes de GBC '98 etait, dans un cadre international, de prendre en compte les differences regionales en autorisant davantage de souplesse et en affectant les criteres d'evaluation de batiments de facteurs de ponderation. Ce point a ete juge essentiel pour que le systeme d'evaluation soit accepte et pour qu'il soit apte a prendre en compte avec precision les meilleures habitudes locales. Toutefois, l'adaptation regionale est complexe et oblige a tenir compte de nombreuses considerations qui sont parfois contradictoires. Cet article analyse l'importance de l'integration des aspects regionaux dans des outils d'evaluation d'une part et, d'autre part, l'avantage de mettre en place un systeme international d'evaluation. L'article se poursuit par une methode qui permettrait d'atteindre un certain equilibre entre les niveaux regional et international d'un systeme d'evaluation universel. Les questions et les solutions proposees en vue d'une consideration ulterieure sont exposees ainsi que les sujets suggeres pour de futures recherches. [ABSTRACT FROM AUTHOR]

This paper reports on experiences from the Swedish participation in Green Building Challenge '98 and ongoing similar work in Sweden. It argues against very simplified environmental assessment methods and recommends, as far as possible, calculation of environmental effects caused by buildings during their life cycle. Participation in the development of the GBC tool provided a broad view of the issues, clarified different opinions in a new field and provided additional stimulation while developing our national assessment methodology, EcoEffect. The environmental assessment of buildings is discussed in relation to the strength and weaknesses of the GBC system. The design and characteristics of 'green buildings' in Sweden is addressed, including ten poster presentations and two case studies presented at GBC '98. Cet article rend compte des experiences liees a la participation de la Suede au projet Green Building Challenge '98 et a des travaux similaires en cours d'execution en Suede. Il procede a l'analyse critique de methodes d'evaluation de l'environnement tres simplifiees et recommande que, dans la mesure du possible, on calcule les incidences sur l'environnement imputables aux batiments pendant leur cycle de vie. La contribution aux travaux de developpement du GBC Tool a permis d'arriver a une vision plus large des problemes, de faire la lumiere sur des opinions differentes dans un domaine nouveau et est a l'origine d'une stimulation nouvelle tout en developpant notre methodologie d'evaluation nationale, EcoEffect. L'evaluation environnementale de batiments est passee en revue sur fond de points forts et de points faibles du systeme GBC. L'article etudie la conception et les caracteristiques des 'batiments verts' en Suede; ce sujet fait egalement l'objet de 10 presentations par affiches et de 2 etudes de cas presentees a la conference GBC '98. [ABSTRACT FROM AUTHOR]

This paper highlights the differences in the customization and use of GBTool during the GBC '98 process by contrasting the assessments of two multiunit residential case-study projects: the Ekoporten project (renovation project), Norrkoping, Sweden and Co-housing project (new build), Cambridge, Massachusetts, USA. The application of GBTool in the two projects suggests that the differences between assessing new and refurbishments is much more significant than initially envisaged. The customizing of the default Performance scales was extensive. The wide range of interpretations that different National Teams placed on the various criteria reinforced the importance of regionally specific assessment methods. The Nonapplicability designation was often applied due to technical difficulties in performing an evaluation rather than whether or not the performance issue was pertinent to the case-study project. The Criticality/Noncriticality designation was ineffectively used during this first testing of the assessment process, primarily due to the absence of meaningful guidance. Although an option existed for National Teams to propose the addition of a limited number subcriteria unique to the region or building type it was not used. The GBC process clearly showed that users need time to become familiar with an assessment procedure and it is evident that a much clearer and consistent set of directives must be provided to assist in any customization process than currently evident within the GBC process. Cet article met en lumiere les differences qui existent dans l'adaptation et l'utilisation du GBTool dans le cadre de la procedure GBC '98 en mettant en opposition l'evaluation de deux projets d'etudes de cas portant sur des unites residentielles multiples: le projet Ekoporten (projet de renovation), a Norrkoping, en Suede et le projet Co-housing (construction nouvelle), a Cambridge dans le Massachusetts (Etats-Unis). L'application du GBTool a ces deux projets laisse entendre que la difference entre l'evaluation de batiments nouveaux et de batiments remis en etat est beaucoup plus importante que ce que l'on pensait a l'origine. L'adaptation d'echelles de performances par defaut a ete poussee dans le detail. Les interpretations nombreuses et diverses que differentes equipes nationales ont donne de divers criteres de recherche, ont renforce l'importance des methodes d'evaluation regionales. La categorie 'inapplicable' ete souvent appliquee du fait des difficultes techniques a executer une evaluation plutot que de savoir si oui ou non la question des performances convenait au projet d'etude de cas. La categorie 'critique/noncritique' a ete utilisee sans aucune efficacite pendant les premiers essais de la procedure d'evaluation, cela etant du, pour l'essentiel, a l'absence de conseils significatifs. Bien qu'il existat une option permettant a des equipes nationales de proposer l'addition d'un nombre limite de criteres secondaires specifiques a la region ou au type de batiment, elle n'a pas ete utilisee. Le procede GBC montre clairement que les utilisateurs ont besoin de temps pour se familiariser avec une procedure d'evaluation et il n'est pas certain qu'il soit necessaire de fournir un ensemble de directives beaucoup plus claires et coherentes pour contribuer a la procedure d'adaptation que ce qui est evident aujourd'hui dans la procedure GBC. [ABSTRACT FROM AUTHOR]

The article discusses the climatic impact caused by the construction of buildings. Topics addressed include the manner in which climatic changes are tackled with the help of building regulatory systems, providing financial benefits to green building strategy implementation by builders and enforcement of building regulations. The article suggests to encourage residential sector to control carbon-dioxide emission.

The human population is rapidly urbanizing, leading many observers to conclude that humans are leaving nature and the countryside behind. This is a perceptual error consistent with the technological optimism inherent in the prevailing expansionist cultural worldview. By contrast, ecological analysis reveals that modern cities are actually increasingly dependent on the goods and services of nature. This fact is merely obscured by technology and urbanization itself. Typical high-income cities appropriate the productive and assimilative capacity of a vast and increasingly global hinterland, resulting in an 'ecological footprint' several hundred times larger than the areas they physically occupy. In the next 27 years, the urban population alone is expected to grow by the equivalent of the total human population in the 1930s. This will double the 1970s urban presence on the Earth. Unfortunately, the conventional development path is biophysically unsustainable, calling for a radical transformation of our thinking about urban form and function. Buildings account for 40% of the materials and about a third of the energy consumed by the world economy. Combined with ecocity design principles, green building technologies therefore have the potential to make an enormous contribution to a required 50% reduction in the energy and material intensity of consumption globally. The needed dematerialization increases to 90% in the high-income countries. Such enormous gains in material productivity are unlikely in the absence of significant ecological fiscal (tax) reform. Ironically, then, the most effective path to green buildings and ecocities may be intensive lobbying for higher taxes on primary energy and materials. La population de la Terre est en voie d'urbanisation rapide, ce qui amene de nombreux observateurs a conclure que l'homme abandonne la nature et la campagne. Cette erreur de perception va de pair avec l'optimisme technologique inherent a la mondialisation culturelle et a l'expansionnisme qui prevalent aujourd'hui. Or, l'analyse ecologique fait apparaitre, au contraire, que les villes modernes sont en expansion dans un contexte de dependance vis-a-vis des biens et des services que procure la nature. Mais cette situation est tout simplement escamotee par la technologie et l'urbanisation. Les villes a revenus eleves s'approprient la capacite de production et d'assimilation d'une vaste zone fonctionnelle globale, en expansion, qui se traduit par une 'empreinte ecologique' dont la surface depasse de plusieurs centaines de fois la surface que ces villes occupent reellement. Dans les 27 prochaines annees, la population urbaine seule devrait voir passer ses effectifs a un nombre equivalent a la population totale du globe de 1930. Ainsi, la part que representaient les villes dans les annees 1970 va-t-elle se trouver doublee. Malheureusement, la filiere du developpement classique n'est pas durable sur le plan biophysique et appelle une transformation radicale de notre maniere de penser en termes de formes et de fonctions urbaines. Les batiments utilisent 40% des materiaux et environ un tiers de l'energie consommes par l'economie mondiale. Associees aux principes de conception de cites ecologiques, les technologies des 'batiments verts' devraient permettre d'atteindre l'objectif vise au niveau de la planete qui est de reduire de 50% la consommation d'energie et l'utilisation de materiaux. Cette dematerialisation necessaire passe a 90% dans les pays a hauts revenus. En l'absence de toute reforme significative de la fiscalite ecologique, de tels gains de productivite paraissent impossibles a atteindre. Il est ironique de penser que la voie la plus efficace vers les batiments verts et les cites ecologiques pourrait passer par le travail de groupes de pression favorables a une augmentation des impots sur les materiaux et l'energie primaire. [ABSTRACT FROM AUTHOR]

The next stage of the Green Building Challenge process incorporating the revised goals for Green Building Challenge and GBTool are reported. This will culminate in a conference in October 2000, Sustainable Building 2000. The critical analysis and feedback from GBC '98 have been incorporated into the revised goals and agenda which are presented in this paper. Cet article rend compte de la prochaine etape du projet Green Building Challenge, notamment de ses objectifs revises et de ceux du GBTool. Ces travaux s'acheveront a l'occasion de la conference d'octobre 2000 intitulee "Sustainable Building 2000" (batiments durables 2000). L'analyse critique et les informations recues de GBC 98 ont ete integrees dans les objectifs revises et dans l'ordre du jour qui sont presentes dans cet article. [ABSTRACT FROM AUTHOR]

Since the 1970s, intense discussions have occurred within the research and practitioner communities on how to assess and influence the environmental performance of buildings. Many different methods, criteria and tools were developed to raise awareness, enable goal formulation, support design and decision-making processes, and evaluate a building’s environmental performance. This development can be retraced through the example of the works of Raymond J. Cole, who made an important contribution to this scientific debate. The integration of environmental performance into a sustainability assessment, the ongoing development of life cycle assessment (LCA) methods, and clients’, financiers’ and assessors’ different demands for environmental performance assessment, raise additional questions and highlight the conflicting goals. Six topics are examined in relation to current developments: the further development of the classic ‘three pillars’ sustainability model; the suitability of assessment criteria and indicators; the handling of technological progress; the discounting of environmental impacts; the environmental assessment of existing buildings; and the further development of legal requirements. ‘Time’ is a key factor relating to LCA, weighing current versus future emissions, ecological value and recycling potential of existing buildings or ‘options’ for different ways to use the building in future. Recommended actions are provided for key stakeholders. [ABSTRACT FROM AUTHOR]

Assessing the economic and environmental life cycle impacts of long-lasting construction projects presents numerous methodological challenges. Three advances over established methods are presented for the life cycle evaluation of construction projects. First, future uncertainty during the project life or study period is explicitly accounted for. This involves moving from a deterministic approach requiring precise data to a probabilistic approach where uncertain variables are defined by ranges. The outcome of life cycle evaluation is then given by probability distributions, generated by Monte Carlo simulation. Second, flexible strategies are considered that allow for adaptation to changing conditions during the project life. Flexible strategies (also modelled by Monte Carlo simulation) incorporate specified ‘life cycle options’ which are exercised if it is advantageous to do so, otherwise they remain unexercised. Third, cost-based life cycle costing (LCC) and environmental life cycle assessment (LCA) are linked in a single LCC+A evaluation tool. There are still differences between cost and environmental evaluation, but the use of a shared framework enables the two aspects to be compared systematically. The two-dimensional ‘ecoportfolio’ diagram presents one way of analysing results. The innovations are demonstrated in a case study that assesses both economic and environmental impacts while accounting for future uncertainties. L’évaluation des incidences économiques et environnementaux du cycle de vie des projets de construction de longue durée présente de nombreux problèmes méthodologiques. Il est présenté trois avancées par rapport aux méthodes établies concernant l’évaluation du cycle de vie des projets de construction. En premier lieu, est explicitement prise en compte l'incertitude future pendant la durée de vie du projet ou la période d’étude. Ceci implique de passer d'une approche déterministe nécessitant des données précises à une approche probabiliste dans laquelle les variables incertaines sont définies par des plages. Le résultat de l’évaluation du cycle de vie est ensuite donné par des distributions de probabilités, générées par la méthode de simulation de Monte-Carlo. En second lieu, il est envisagé des stratégies flexibles qui permettent l'adaptation à des conditions changeantes pendant la durée de vie du projet. Ces stratégies flexibles (également modélisées par une simulation de Monte-Carlo) intègrent des « options de cycle de vie » spécifiées qui sont levées s'il est avantageux de le faire, et qui sinon demeurent non levées. En troisième lieu, l'estimation du coût du cycle de vie (LCC) basée sur les coûts et l’évaluation environnementale du cycle de vie (LCA) sont liées dans un outil unique d’évaluation LCC+A. Il existe encore des différences entre l'estimation du coût et l’évaluation environnementale, mais l'utilisation d'un cadre partagé permet de comparer systématiquement ces deux aspects. Le schéma bidimensionnel de « l’éco-portefeuille » présente une manière d'analyser les résultats. Les innovations sont montrées dans une étude de cas qui évalue les incidences à la fois économiques et environnementales tout en rendant compte des incertitudes futures. Mots clés: adaptation économie du bâtiment stratégies de conception flexibilité évaluation du cycle de vie coût du cycle de vie options réelles incertitude [ABSTRACT FROM AUTHOR]

The current state and future challenges of energy and buildings research are explored from the perspective of the social study of science. Major trends in knowledge production are considered for practices within current energy and buildings research. New forms of knowledge production hold the potential to provide clearer strategies to overcome barriers between researchers and practitioners. These are investigated through an explorative survey of researchers based on their own accounts of energy and buildings research, their expectations of future challenges, and their perceptions of ‘good’ science. Two sets of challenges from knowledge production arise for building energy research. First, with an increasing focus on environmental and other impacts of the research, the framing and definition of these extra-scientific factors will become a significant challenge for researchers. Second, as buildings become simultaneously more complex and more connected, the already existing need for the integration of different kinds of expertise will increase further. L'état actuel et les défis futurs de la recherche en matière d'énergie et de bâtiments sont examinés du point de vue de l'étude sociale des sciences. Les principales tendances de la production de savoir sont envisagées sous l'angle des pratiques existant dans les recherches actuelles sur l'énergie et les bâtiments. De nouvelles formes de production de savoir offrent la possibilité de fournir des stratégies plus claires pour surmonter les barrières entre chercheurs et praticiens. Celles-ci sont étudiées au moyen d'une enquête exploratoire conduite auprès des chercheurs, basée sur leurs propres récits des recherches menées sur l'énergie et les bâtiments, sur les défis futurs qu'ils prévoient, et sur leurs perceptions de la « bonne » science. Deux séries de défis posés par la production de savoir découlent des recherches sur l'énergie dans le bâtiment. Tout d'abord, en mettant davantage l'accent sur les incidences environnementales et autres de la recherche, l'encadrement et la définition de ces facteurs extra-scientifiques deviendront un défi considérable pour les chercheurs. Deuxièmement, au fur et à mesure que les bâtiments gagnent simultanément en complexité et en connectivité, le besoin déjà existant d'intégrer différents types de compétences augmentera encore. Mots clés: bâtiments, énergie, collaboration interdisciplinaire, production de savoir, programme de recherche, science, durabilité [ABSTRACT FROM AUTHOR]

Understanding how and why cities and the urban fabric contribute to energy consumption and greenhouse gas (GHG) emissions is a crucial issue regarding climate change and resource scarcity. A critical review is presented of the calculation tools, models, and assessment systems that deal with energy consumption and GHG emissions from buildings at the district and city scales. The review encompasses international assessment systems and technical models developed in Japan, North America and Europe. The relationships and connections between policy and research within these systems are examined. Chronic systemic failures are highlighted that should be addressed rapidly in the research agenda. The negative impacts are considered in terms of the operational potential due to the use of rough aggregation methods. The analysis emphasizes the need for more systemic, multi-scale and transverse approaches to deal with the intrinsic complexity of the urban fabric. Four intervention points for urban efficiency are proposed: urban morphology, buildings' efficiency, systems' efficiency and individual behaviours. Harnessing all of these would improve the potential of models and assessment systems. Combining these urban efficiencies would have a multiplier effect in terms of actual outcomes in reducing energy consumption. Comprendre comment et pourquoi les villes et le tissu urbain contribuent à la consommation énergétique et aux émissions de gaz à effet de serre (GES) est un problème crucial en matière de changement climatique et de pénurie des ressources. Il est présenté un examen critique des outils de calcul, des modèles et des systèmes d'évaluation qui traitent de la consommation énergétique et des émissions de GES des bâtiments à l'échelle du quartier et à celle de la ville. Cet examen englobe les systèmes d'évaluation et les modèles techniques internationaux élaborés au Japon, en Amérique du Nord et en Europe. Les relations et les liens entre politique et recherche au sein de ces systèmes sont examinés. Sont mises en évidence les défaillances systémiques chroniques auxquelles il devrait être rapidement remédié dans le programme de recherche. Les incidences négatives sont envisagées du point de vue du potentiel opérationnel en raison de l'utilisation de méthodes approximatives d'agrégation. L'analyse met l'accent sur le besoin d'approches plus systémiques, multi-échelles et transversales pour gérer la complexité intrinsèque du tissu urbain. Quatre points d'intervention sont proposés pour l'efficacité urbaine : la morphologie urbaine, l'efficacité des bâtiments, l'efficacité des systèmes et les comportements individuels. Maîtriser tous ces éléments améliorerait le potentiel des modèles et des systèmes d'évaluation. La combinaison de ces efficacités urbaines aurait un effet multiplicateur en termes de résultats effectifs dans la réduction de la consommation énergétique. Mots clés: système d'évaluation, bâtiments, échelle de la ville, échelle du quartier, modèle énergétique, programme de recherche [ABSTRACT FROM AUTHOR]

The background to and feedback from the UK team on the Green Building Challenge process in the UK is provided along with a commentary on the future development of the environmental assessment of buildings. Unique amongst the GBC national teams, the UK team chose buildings which had undergone post-occupancy evaluation. As a consequence, buildings were evaluated on their design, construction and operation phases. This additional information on actual rather than predicted performance provides a number of important lessons for the environmental assessment of buildings. Future expectations for the development of GBC from the UK perspective include providing proper credit for design features such as low-energy passive cooling and daylighting, modifying the assessment weighting system to provide more reliable comparison or benchmarking between design solutions, providing a practical international assessment method for comparison or benchmarking, incorporating post-occupancy evaluation to validate assessment methods and tools. Ease of use is important and GBC could usefully be simplified to consider the point of application in design, post-design certification and post-occupancy. Environmental assessment of buildings in the future must evolve within a wider context of local Agenda 21 sustainable development criteria. Cet article rappelle les informations fournies a l'equipe britannique du projet Green Building Challenge et celles recues en retour, et s'accompagne d'un commentaire sur la facon dont va evoluer l'evaluation environnementale des batiments. L'equipe britannique se distingue des autres equipes nationals en ce sens qu'elle a choisi des batiments qui ont ete entierement evalues apres le depart des occupants, evaluation qui s'est donc faite au niveau de la conception, de la construction et de l'exploitation de ces batiments. Ces informations complementaires sur des performances reelles plutot que prevues constituent autant d'enseignements importants pour l'evaluation des batiments sur le plan de l'environnement. Du point de vue britannique, l'evolution du GBC devrait donner toute leur credibilite a des caracteristiques de conception telles que le refroidissement passif par faible energie et l'eclairage diurne, modifier le systeme de ponderation pour deboucher sur des comparaisons plus fiable entre solutions conceptuelles, aboutir a une methode internationale d'evaluation pratique a des fins de comparaison ou d'etalonnage, incorporer une evaluation apres occupation pour valider les outils et les methodes d'evaluation. La facilite d'utilisation est un aspect important et le GBC pourrait etre simplifie, utilement, pour considerer le point d'application au niveau de la conception, de la certification apres conception et de la fonctionnalite. L'evaluation environnementale des batiments devra evoluer en tenant compte de l'elargissement des criteres locaux de l'Agenda 21. [ABSTRACT FROM AUTHOR]

Editorial. Provides a critical review of Green Building Challenge 1998, a two-year process of international co-operation in developing and testing a building environmental assessment method. Benchmark of international progress in designing environmentally progressive buildings; Building environmental assessment methods.