Interpreting environmental impacts in building design: Application of a comparative assertion method in the context of the EPD scheme for building products

Abstract

Due to the profound impact that building sector has on the environment and consequently the sustainability of our society, the evaluation of environmental impacts through life cycle assessment (LCA) should become part of building design. The number of published environmental product declarations (EPDs) is growing, which indicates that they can become valuable tools for building designers to evaluate the environmental performance of construction works. We identified that in the current EPD scheme an important part is missing – the results interpretation. In order to evaluate the environmental performance of buildings or their components and elements, the designer is “forced” to conduct a comparative assertion on a population of alternatives. The paper explores the results interpretation of LCA data in the context of the EPD scheme for building products and presents a comparative assertion method, which could guide designers through the results interpretation step of LCA. The proposed soft comparative assertion method was tested on a sample of external wall assembly alternatives and the results show that it significantly simplifies the LCA results interpretation and enables straightforward decision making. However, the method is not yet a fully functional tool and should be upgraded in order to make the decision process more robust and less subjective. With this paper we wish to encourage further research on the described topic, which is vital in order to add credibility to the EPD scheme as an instrument for lowering the environmental impact of the building sector.