LCA Study Investigating the Impact of Construction on Sloping Sites

Abstract

The building sector is increasingly aware of the environmental impact of buildings. In Australia buildings produce approximately 23% of this country's total Green House Gas (GHG) emissions. Life Cycle Assessment (LCA) studies are helping in the development of sustainable buildings; however, not much has been done on the impact of construction processes including cut and fill excavation. This report provides FWPA, designers and practitioners in the construction industry with an understanding of the environmental impact of cut and fill excavation construction on sloping sites (from 1:10 to 1:2 gradients) in NSW. The study quantifies all the significant LCA inputs and outputs to the cut and fill excavation, retaining wall and associated subsoil drainage works. It also developed an evaluation matrix that compares environmental impacts and GHG emissions. The LCA considered all impacts of the manufacture of building products, their transport, the construction and operating phases, and the final disposal of the product after its useful life. It was evident that a steep slope substantially increases the cumulative energy demand and greenhouse gas emissions. Alternative solutions such as suspended flooring systems may minimise the disturbance to the land and natural habitat.