Review of Factors Affecting the Incorporation of Nature-Based Solutions in Circular Construction

Abstract A closed-loop circular economy (CE) in the construction sector requires the coordinated functioning of both technical and biological cycles; however, current practices in the circular construction predominantly emphasise the technical cycle through the use of secondary materials. Their processing and usage can generate circular rebound effects by increasing embodied emissions that undermine the regenerative outcomes of CE. Nature-based solutions (NbS) can support the biological cycle by acting as carbon sinks through ecosystem services, thereby complementing material circularity and enabling CE loop closure. This review aims to explore the temporal distribution of research for the incorporated approach and categorise the applications across the three implementation scales. It further identifies the challenges and enablers for incorporating secondary materials with NbS in the circular construction. This paper contributes by identifying the 17 applications, including 9 real-world cases, providing a rationale for this incorporation to close the CE loop in the construction sector. It further contributes by proposing the four interdependent strategies that can facilitate the implementation of this incorporated approach in the construction sector. The strategies include: nature-integrated circular governance, policy coupling for technical-biological cycles, circular-nature value architectures, and community-embedded regeneration. The findings provide a baseline for future policy design and industry practice to close the CE loop and deliver regenerative outcomes in the circular construction practices.