Strategies to improve building environmental and economic performance: an exploratory study on 37 residential building scenarios

Purpose With a contribution of 39% to greenhouse gas (GHG) emissions, reducing the environmental impacts of buildings plays an undisputed role in achieving climate goals. Therefore, the development of projects with a low carbon footprint is of crucial importance. Although several active and passive solutions as well as design strategies have been developed, identifying critical levers to minimise GHG emissions and the cost of future building projects is still a problem faced every day by designers. Methods Motivated by this knowledge gap in this study, we conducted a life cycle assessment (LCA) and life cycle cost analysis (LCCA) of a residential building situated in Austria. To identify the critical levers for reducing impacts and cost, 37 scenarios with three different advanced energetic standards are created. The scenarios with the various standards are developed through the combination of different construction materials, insulation materials and technical building equipment. In the eco-efficiency assessment (LCA and LCCA), a reference study period of 50 years is assumed. The life cycle of the building scenarios was analysed according to the European standard EN-15978. Results Results show that improving the energetic standard does not yield an overall cost savings potential. The additional construction cost (23%) for energy efficiency measures, including thermal insulation and change of technical building equipment, is higher than the reduction potential in operating cost over 50 years. On the other hand, the improvement of energetic standards allows a reduction of the environmental impacts by 25%. Conclusions To ensure a cost-optimal environmental improvement of buildings, it is crucial to conduct an eco-efficiency assessment during the design process of energy-efficient buildings. This study shows how improving the energetic standard of buildings can reduce environmental impacts with slightly increased life cycle cost.