Environmental impacts and costs of residential building retrofits – What matters?

Abstract

Building resilient communities plays an important role in the face of climate change and other societal stressors. Life-cycle assessment (LCA) approaches can assist stakeholders and policy makers to promote good environmental practices and support climate-change mitigation and adaptation. However, LCA approaches face several challenges when applied to buildings. Buildings are complex systems that result in data-intensive processes. For this matter, it is important to identify the most influential attributes to efficiently provide environmental and cost feedback and streamline the building decision-making process. The main objectives of this article are: apply a streamline approach to assess the environmental and cost performance of building retrofits for different types of houses and occupancy patterns, in alternative climate locations; and perform a comprehensive sensitivity analysis to identify key drivers of environmental and cost impacts. The most influential attributes to climate change impacts are the same irrespective to location, type of house and wall-system; however, they differ depending on occupancy. The key drivers to eco-efficiency are discount rate, and exterior-wall insulation. The most influential attributes can change depending on family size or set-point meaning that an early definition of these attributes can change which decisions are the most important in an early design stage.