Building impact assessment—A combined life cycle assessment and multi-criteria decision analysis framework

Abstract

In recent years, net zero energy building has becoming a trend in the building industry, with the aim to reach a carbon-neutral goal by 2050. Building codes, regulations, directives, and design guidelines have primarily focused on a building’s performance—particularly on energy performance. Meanwhile, there is increasing interest in the co-benefits of a building’s energy efficiency, such as human health and water conservation, which are less addressed in building performance assessments. To respond to these critics and the research gap in the current energy-centric building performance assessment framework, this paper presents a methodological framework to assess a building’s impact on energy, environment (smog, global warming, ozone depletion), water (acidification, eutrophication) and human health. This integrated assessment framework is based on life cycle assessment (LCA) and multi-criteria decision analysis (MCDA). The aim of this proposed framework is to: (1) shift the mindset from performance to impact when assessing building design solutions; (2) provide a broader building assessment framework that integrates energy, water, the environment, and health; and (3) demonstrate the feasibility of the proposed integrated assessment framework. This paper first outlines the two missing components of the current net zero energy building assessment method, followed by a description of other building impacts that should be included in building. More precisely, three additional impact categories were identified: the environment, water, and human health. Within each impact category, multiple impact criteria were included. Then, a multi-criteria analysis was applied to rank the design alternatives. Lastly, a case study was used to demonstrate the validity of this proposed framework, the original building and three alternatives were evaluated. The results show current single criteria (energy-centric) approach is not adequate since 3 different alternatives performed differently in variety impact categories. In general, design alternatives with low-impact materials generate less human health impact, while not always correlate with life cycle energy saving. The findings approved that the proposed assessment framework can be applied to the whole building as well as to individual building components or assemblies.