The difficult interpretation of LCA when reusing components

Interpreting Life-Cycle Assessments (LCA) when reusing components is delicate and no consensus exists. Yet, reuse is a key strategy for implementing a circular economy and reliable metrics are needed.

In our recent paper published in "Sustainable Cities and Society", we discuss this issue by applying six common allocation methods to three scenarios of material sourcing: sourced components are newly produced and reusable; sourced components are reused and reusable; or sourced components are reused and at their end of life.

The measure of embodied carbon in the current renovation/extension of the Kopfbau Halle 118 (Winterthur, CH) is taken as a case study. The building is unique in Switzerland because the vast majority of its components (load-bearing, envelope, partitioning) are renewable or reclaimed from other buildings. The building is designed by Baubüro in situ and we are thankful that we could use their data.

All in all, we argue that discrepancies between methods are so high that LCA is not sufficient to measure the environmental quality of reuse practices.

• Preprint version available here: https://infoscience.epfl.ch/record/278413
• Journal version available here: https://reader.elsevier.com/reader/sd/pii/S2210670720305436 - free download until Sept.15, 2020

Authors: Catherine De Wolf, Endrit Hoxha, Corentin Fivet - Structural Xploration Lab, EPFL