Environmental Impacts over the Life Cycle of Residential Buildings Using Different Exterior Wall Systems

Abstract

This study analyzed the environmental impacts of a single-story residential building using different exterior wall systems. The environmental impacts over the complete life cycle of the residential buildings were determined and compared using the following indicators: air pollution index, energy consumption (embodied and operational), global warming potential, resource use, solid waste emissions, and water pollution index. The exterior wall systems analyzed were concrete block, poured in-place concrete, insulated concrete, traditional 0.05 mx0.1 m by 0.4 m (2 in.x4 in. by 16 in.) on center wood frame, traditional 0.05 mx0.15 m by 0.6 m (2 in.x6 in. by 24 in.) on center wood frame, and steel stud framing. Additionally, structural insulated panels were modeled for the operational energy of the building. For each scenario, the designs were based on the minimum R value required by the International Building Code. ATHENA, a life-cycle assessment software tool, and eQuest, an energy usage modeling software tool that calculated the operational energy of the building, were used to evaluate the environmental impacts of the building, during the construction, use, and end of life phases, for each scenario. The results show that in the preuse phase, the insulated concrete buildings produce the greatest impact on the environment followed by the concrete block, poured in-place concrete, and steel stud buildings.