Life cycle assessment of residential buildings

This work proposes a model to conduct the life cycle assessment of a U.S. residential building, from a construction materials and energy consumption standpoint. It illustrates three case studies in different U.S. Cities (Pittsburgh, San Antonio, and Ann Arbor), considering three life-cycle phases: Construction, usage, and disposal. Direct and indirect environmental effects among the different economic sectors were assessed along the housing life throughout the on-line system “economic input-output life cycle assessment” (Carnegie Mellon). Construction characterization was done using an off-the-shelf tool (RSMeans). The on-line energy consumption estimator system “Home Energy Saver” (DOE & EPA) was used to estimate the home energy consumption along its usage stage. Statistical data were used to define standard patterns for housing remodeling and maintenance on the whole, it was intended to frame the study on the general principles of the ISO 14040's series. Inventory results were interpreted by a multi-criteria evaluation method proposed for three suggested global environmental indicators. In the three case studies the environmental stressors most important for the construction phase were the same (soil toxicity, ores depletion, and polluted air). As for the usage phase, results from the three case studies coincided in that this was the most important phase in the life-cycle assessment of a residence. In this research approach, the disposal phase played a minor role. It was also conducted a sensitivity analysis that proved a sound model performance, and results were discussed from different standpoints.