Building-Level Circularity Assessment in Urban Regeneration: A Mediterranean Case Study

Abstract As the urgency to operate within planetary boundaries intensifies, adopting the circular economy (CE) in the built environment has become essential to mitigate environmental emissions, resource depletion, and waste generation. However, CE implementation at the building level remains fragmented in rapidly urbanizing lower-income countries. There is a pressing need for robust assessment to quantify the current level of circularity and identify context-specific opportunities for improvement. This study aims to evaluate the circularity potential of a residential building block in an urban regeneration project in Izmir, Türkiye, using the Whole Building Circularity Indicator (WBCI) applied to assess circularity across key lifecycle stages and system levels. The results indicate a WBCI score of 0.17 (on a scale of 1 fully circular to 0 fully linear) and a moderate flexibility of 0.70. This reflects a linear building profile driven by virgin materials, mass-intensive construction, limited adaptability, disassembly, and low end-of-life recovery potential. The structure layer presents the lowest system circularity score of 0.11. The study contributes to the literature on building circularity assessment by highlighting the critical role of the assessment framework in guiding the built environment toward more resource-efficient and sustainable outcomes in Mediterranean contexts, and offers practical insights to inform policy development.