Exploring the Missing Link between Life Cycle Assessment and Circularity Assessment in the Built Environment

The built environment—with its significant environmental impact and long lifespan—is a key sector in which to implement circular economy principles. So far, however, a coherent framework with circularity indicators has not yet been established. While Life Cycle Assessment (LCA) is commonly practiced to quantify the total environmental impact, it is designed and intended to assess linear life cycles, making it unsuitable for circularity assessment. Thus this paper explores an objective method to link LCA to a semi-quantified circularity indicator. Four variants of external wall designs of two case studies are analyzed. The explored possibilities of linking LCA results or mass input flows to the circularity indicator show differences in outcome. Furthermore, the analysis shows that decision-making can be affected by choice of assessing only a circularity indicator, an environmental impact indicator, or mass input flows, as opposed to a scenario in which a linked approach of these parameters is applied.