Streamlined life cycle assessment of domestic structural wall members

Life Cycle Assessment (LCA) methods, while accepted as the only valid method of evaluating the environmental impacts of buildings, are generally too cumbersome for use by building designers. Therefore, streamlined LCA methods have been developed, which involve either reducing the system boundary of the analysis, reducing the breadth of environmental parameters considered, or using less reliable statistical data. However, currently available streamlined LCA data tends to be inappropriately applied, leaving gaps in the systems boundary. The development of more accurate and complete streamlined LCA data and methods is therefore required, and the author describes some recent developments. Timber wall studs and steel wall studs are compared to recycled steel wall studs, using a new hybrid LCA method based on input-output data. Compared to previous results, steel can have lower greenhouse gas emissions than timber in certain circumstances. Furthermore, the use of input-output data as the basis for the LCA means that reliable data from industry can be incorporated within a comprehensive systems boundary.