A Framework for Comparing Assessment Criteria of Environmental and Sustainability Rating Systems

Nowadays, enviromental impact of buildings is assessed by several sustainability rating systems. Analyzing relative importance and prioritizing of assessment criteria, as the principal measures for rating systems, indicate the general trend of those systems in accordance with three pillars of sustainability, i.e. environment, economics and society. Having gathered data in the form of library-based study, this paper proposes a framework to compare and analyze the criteria of widely-used assessment systems, including BREEAM, LEED, CASBEE, DGNB and HQE. By chossing an analytical-comparative method, assessment criteria for 5 rating systems are explored and classified. In order to acquire the relative importance of each criterion, weigthing coefficients are adopted and the weighted percentages are calculated. The comparative framework organized by three principles of sustainability, mainly covers 11 categories including Energy, Water, Site, Environmental Loads, Material, Waste, Indoor Environmental Quality, Socio-cultural issues, Economics, Technical and Functional Quality and Sustainable Management. Sub-criteria of each category provide the possibility for evaluating rating systems sufficiency at the micro level. Rating systems concepts and trends have a major role in organizing criteria structure. For example, DGNB, which has an assessment structure in compliance with the three principles of sustainable architecture, much of criteria are assigned to economic and social issues, while BREEAM, LEED and HQE, considered as first generation of rating systems, mostly deal with environmental issues. In the holistic systems such as DGNB and CASBE issues such as performance, technical capabilities and building service are generally highlighted, whereas atomistic systems such as BREEAM, LEED and HQE give importance to preservation of resources including energy, water, land, etc. However, in both systems, energy and indoor environment quality are significantly considered.