A BIM-based decision support system for circularity and sustainability assessment in the early design stages

The transition to a circular economy aims to reduce the consumption of raw materials and minimise waste. Building circularity assessment (BCA) at the early design stages is crucial for achieving circularity and sustainability objectives, which are often considered separately and can occasionally conflict. Although building information modelling (BIM) has been leveraged to support decision-making, current BIM-based BCA tools focus mainly on geometric information extraction without offering decision-making support. To address these gaps, this study adopts a design science research (DSR) methodology to develop a BIM-based decision support system (DSS) that integrates BCA with life cycle assessment (LCA) and life cycle costing (LCC), supporting simultaneous evaluation of circularity and sustainability from a life cycle perspective aligned with the EU Level(s) framework, while facilitating trade-offs and the straightforward comparison of design alternatives. Multi-criteria decision analysis is employed to facilitate trade-offs and selection among design alternatives. The DSS enables assessment at the element, system, and building levels and enhances traceability and documentation via circular material passports and a material bank interface. As a pilot demonstrated on a simplified case study, the proposed framework was tested in a controlled environment through a proof-of-concept simulation experiment using a hypothetical building model and generic data. This conceptual validation demonstrates the feasibility and utility of the artefact. The empirical validation with practitioners and real building projects remains a matter for future research. The DSS shows the potential to optimise material use and resource efficiency, contributing to the twin transition of a sustainable circular economy and digitalisation.