The circular economy (CE) paradigm has helped the building sector reduce its environmental impacts. However, existing circularity assessment (CA) frameworks have not guided practitioners in making circular decisions at the project frontend. This paper develops and validates a CA framework to inform circular decision-making (DM) at an early stage in building projects.
The proposed CA framework, comprising 12 circularity indicators (CIs), was calibrated using the analytic hierarchy process. A state-of-the-art case study, involving a cutting-edge engineering building at the forefront of the sustainability design stage, was undertaken to validate the proposed model and identify potential challenges through the lens of the theory of planned behaviour (TPB).
(1) Current building sustainability assessments lack clear conceptual contours between different pathways to sustainability due to a focus on carbon/energy instead of materials flows; (2) the fragmentation of project roles resulted in a lack of collaborative effort in CA, with designers primarily driven by clients’ requirements and often emphasising traditional sustainability metrics over circularity benefits; and (3) the transition to CE in the built environment has been partial and completing the transition involves a behaviour change case including all stakeholders.
This study contributes to the current body of knowledge by revealing behavioural challenges related to CA within the field of circular building design. It supports building designers to embed CA in building projects’ front-end DM. It also refocuses policymakers’ attention to embodied carbon, circular public procurement and economic incentives as levers for driving CA implementation.
The validation of a novel set of CIs using a cutting-edge building project case study offers unique insights, underpinned by TPB, into behavioural challenges, relevant to incorporating circularity into frontend DM processes.
