New insights into technical challenges and barriers for implementing circular strategies within the built environment

Achieving Net Zero targets will require a fundamental transformation of the building sector. Circular economy (CE) is seen as a key enabler of sustainability, offering benefits such as resource efficiency, waste minimization, and carbon footprint reduction. Despite growing interest, CE adoption in the building sector remains limited, reflecting persistent technical and organisational implementation challenges. This study thus examines technical challenges and barriers to implementing circular strategies by offering stakeholder perspectives in the building sector across multiple regions. Specifically, this study investigate which technical barriers most constrain circular practice across the building lifecycle and how their perceived importance varies by sector, region, and experience. Our study draws on (i) a structured narrative review literature review of key documents such as academic articles, standards, policy reports, strategic roadmaps, and white papers, and (ii) a multi-region survey(n=270) of stakeholders in the building sector and adjacent supply chains. Meanwhile, this study analyse barrier categories, interoperability of tools/data, documentation and traceability, and capability gaps with map them to lifecycle stages, and compare priorities across respondent groups using descriptive contrasts. Through a detailed examination of stakeholders' priorities, spanning materials, products and components, constructed building stocks, and urban living environments, this study identifies where technical barriers most constrain circular practice along planning/design, construction, operation, and end-of-life. The findings highlight immediate technical priorities, interoperability of tools/data, documentation and traceability, and practitioner capabilities with practical implications for planners, engineers, and public agencies. Consistent with this focus, interoperability and documentation/traceability outrank policy instruments as near-term constraints across roles and regions; capability gaps are more salient among early-career respondents, while public agencies emphasise indicators/monitoring and industry prioritises feasibility and transaction costs. They provide a bounded, practice-oriented map of technical constraints and inform staged actions to advance circular practice. For scope clarity, coverage is multi-region rather than global, and sectoral statistics on emissions, energy use, and waste are discussed in the Introduction with sources.