Circular and adaptable building transformation: Reconceptualization, practice exploration, framework co‑development and implementation

Existing buildings are changing assets, altered in response to various external or internal triggers for change. Often, change can occur in the form of adaptive reuse – also known as building transformation. Therefore, promoting adaptability in transformation is necessary to cope with the inevitability of building changes. Building transformation is considered an effective practice contributing to the circular economy (CE) and building adaptability as a prerequisite for circular design. However, previous research pointed out that building stakeholders lack knowledge about the alignment between CE and adaptive reuse. This study aims to provide building and real estate practitioners with a guiding framework for promoting circularity and adaptability in adaptive reuse projects. A quadrant research design was used in this study to develop and apply the framework in practice. The four components of this research are four stepwise studies, namely theoretical – an integrative literature review, empirical – multiple case studies, participatory – framework co-development, and actionable – framework implementation. First, the integrative literature review contributed to theoretically conceptualizing the underlying concept of this research – the circular building adaptability (CBA), which brings together circularity and adaptability. Second, the multiple case studies contributed to extracting lessons learned about applicable CBA strategies in adaptive reuse and their enabling and inhibiting factors. Third, the participatory study contributed to co-developing a descriptive framework for CBA in adaptive reuse (CBA-AR). Finally, the action research study contributed to testing and improving the usability and effectiveness of the CBA-AR framework based on observing, acting, and reflecting on a case project.