“This study provides an overview of Life Cycle Assessment (LCA) as applied to selected low slope roofing systems used widely throughout North America. LCA is a scientific approach to evaluating the environmental impact of a product or system throughout its life cycle. The objective of the study was to establish up-to-date life cycle impact data based on a critical review of previous LCA studies and new life cycle inventory data acquired from industry and public sources. The study examined roofing systems employing a variety of roofing membranes, including EPDM, TPO, PVC and SBS modified bitumen.”