Towards the development of a simplified LCA-based model for buildings: recycling aspects

Abstract

Disponible à l'adresse : http://leso.epfl.ch/files/content/sites/leso/files/download/publications/cisbat_proceedings_final_download.pdfInternational audienceThe building sector identified as a main contributor of energy and resources consumption contributes to many environmental impacts such as resources depletion or climate change. The identification, quantification and analysis of the main flows of matter, energy and pollution through the building system by means of appropriate methods can help to provide knowledge and tools for decision making. The Life Cycle Assessment (LCA) is, in this context, a method which can be applied to study the environmental impacts of buildings. Several LCA-based environmental analysis tools have been developed over the past few years. However, the relevance of such tools is often questioned. The methodological choices seriously influence the results of the analysis particularly in terms of data quality, type and number of environmental indicators, recycling take-account, modelling of the end of life (EOL) and more widely the chosen system boundaries. As a result of all of these shortcomings, the LCA studies are often seen as being too complex for application in the design process. In this article, we present the current LCA models characteristics for buildings. Then, we focus the analysis on the recycling and EOL of products by presenting the current practices. It has been found that current LCA models do account for material, recycling and end of life aspects but in a way so that it is not an easy task to evaluate the design choices for these aspects. Through the adopted methodology, main recycling criteria of LCA models were identified and consequences of defining a proper boundary system for a LCA model are discussed. We conclude by discussing the challenges of improving the LCA methodology for buildings