Streamlined environmental and cost life-cycle approach for building thermal retrofits: A case of residential buildings in South European climates

Abstract

Building retrofits are often motivated by the desire to improve the energy efficiency of a building. However, environmental burdens associated with additional materials used to accomplish energy efficiency are not usually taken into account. Life-cycle assessment (LCA) and life-cycle cost assessment (LCCA) approaches have been extensively applied to analyze building environmental impacts and costs. However, LCA and LCCA are time-consuming and resource-intensive and are usually performed in late design stages when significant reduction in total life-cycle impacts is costly to achieve. The aim of this article is to present an integrated, streamlined LCA-LCCA approach to building retrofits to provide feedback on environmental impacts and costs at early-design stage decisions. We propose a framework that fully integrates a streamlined embodied LCA, statistical-based operational energy, and cost models. This approach incorporates uncertainty to address the lack of information in early design stages by using the building attribute to impact algorithm approach, which includes structured under-specification and probabilistic triage. An automated process enables several scenarios to be assessed and compared as a means of better informing designers of the relative environmental impact of materials and dimensioning choices. It is demonstrated that by selecting very few attributes and then comparing several options, robust retrofit decisions can be made in early-design stages, thereby promoting a reduction in environmental impacts and costs.