Global methodology for sustainability assessment : integration of environmental LCA in rating systems

Sustainable construction is a multidimensional concept that is based in the performance of a construction through the three dimensions of sustainable development: environment, society and economy. Sustainability assessment and rating systems are intended to foster more sustainable building, design, construction, operation, maintenance and disassembly/ deconstruction by promoting and making possible a better integration of environment, societal, functional and cost concerns with other traditional decision criteria. The use of improved materials and building technologies can contribute considerably to better environmental life cycle and then to the sustainability of the constructions. Although, life-cycle assessment (LCA) is considered the best method to evaluate the environmental impacts, most of the sustainability rating systems are not comprehensive or consistently LCA-based. The reason is mainly linked to the complexity of the stages of a LCA. Based in the harmonization work that is being carried out by the European Centre of Normalization (CEN) and by the iiSBE Portugal in the development of the Portuguese rating system (SBToolPT), this paper will discuss the difficulties and solutions to turn possible the integration of more accurate environmental assessment methods in rating systems.