A systematic literature review on circularity assessment indicators and frameworks in the built environment

A wide range of circularity assessment indicators and frameworks for the built environment have been developed in recent years to support the transition to a circular economy (CE). However, few studies have systematically reviewed the available circularity assessment methods beyond the building scale, and there is limited analysis of non-quantitative assessment methods. Therefore, this systematic literature review of 66 studies identifies and analyzes existing circularity assessment indicators and frameworks for the built environment across building, neighborhood, and city (and beyond) scales, providing a comprehensive overview of the state of the art and key directions for future research. The analysis identifies 148 quantitative, 160 semi-quantitative, and 152 qualitative indicators, which are categorized based on their application in circularity assessment, either individually or as part of indicator sets in frameworks. The results show that existing indicators cover five key dimensions of circularity; however, the interrelationships between these dimensions remain unclear and are rarely addressed. Most indicators are applied at the building level, while larger spatial scales remain less developed. These findings highlight the complexity of the current state of the art, driven by the extensive number and fragmentation of existing indicators. Based on this, this review recommends future research directions to enhance circularity assessment methodologies, with an emphasis on refining existing methods, improving decision-support mechanisms, and moving toward standardization. By synthesizing current knowledge and identifying critical research needs, this study serves as a starting point toward standardizing circularity assessment and thus supporting the adoption of CE principles in the built environment.