Design consequences of differences in building assessment tools: a case study

Environmental assessment tools for buildings are emerging rapidly in many countries. Do different assessment tools influence the design process and also guide 'green' building projects in different directions? Three assessment tools, Leadership in Energy and Environmental Design for New Construction (LEED-NC), Code for Sustainable Homes (CSH) and EcoEffect, were tested in a case study project in Sweden: a new multi-storey residential building called Gronskar. The content and results of the three assessment tools were compared in general, while issues in the three core common categories of Energy, Indoor Environment and Materials Waste were compared in more detail. The assessment results for the case study building varied with the three tools, and the design strategies and tactics to improve the overall rating of the building project differed for each tool. This confirms that the tools can influence sustainable building in different directions and illustrates insufficient consensus between assessment tools in terms of issues, criteria and weighting. The divergent results highlight the need for an appropriate structure of assessment tools that are both environmentally relevant and practically useful. 'on assiste dans de nombreux pays a l'emergence rapide d'outils d'evaluation environnementale. Des outils d'evaluation differents influent-ils sur le processus de conception et orientent-ils egalement les projets de batiments << verts >> dans des directions differentes? Trois outils d'evaluation, le systeme Leadership in Energy and Environmental Design for New Construction (LEED-NC pour les constructions neuves), le Code for Sustainable Homes (Code pour des Logements Durables - CGH) et EcoEffect, ont ete testes dans le cadre d'un projet de construction situe en Suede et utilise comme etude de cas : un nouvel immeuble residentiel a etages multiples denomme Gronskar. Le contenu et les resultats de ces trois outils d'evaluation ont ete compares sur un plan general, tandis que les points relevant des trois principales categories communes - Energie, Environnement Interieur et Materiaux et Dechets - ont ete compares de maniere plus detaillee. Concernant l'immeuble utilise comme etude de cas, les trois outils ont donne des resultats d'evaluation qui differaient, et les strategies et tactiques de conception visant a ameliorer la notation globale du projet de construction etaient differentes pour chaque outil. Ceci confirme que ces outils peuvent influer sur un batiment durable a differents niveaux et illustre le consensus insuffisant entre les outils d'evaluation en termes d'enjeux, de criteres et de ponderation. Ces resultats divergents soulignent la necessite de pouvoir disposer d'outils d'evaluation presentant une structure adaptee pour que ceux-ci soient a la fois pertinents pour l'environnement et d'une utilite pratique. Mots cles: methodes d'evaluation, outil d'evaluation, evaluation des batiments, conception des batiments, Code for Sustainable Homes (Code pour des Logements Durables - CSH), EcoEffect, evaluation environnementale, Leadership in Energy and Environmental Design (LEED), batiment durable.