Implementation and Consideration of Circularity Within International Sustainability Assessment Methods

The construction sector is a major contributor to environmental degradation, prompting the need for integrating sustainability into its practices. This need has driven the development of sustainability assessment methods across various scales of the built environment. Simultaneously, the recent emphasis on Circular Economy (CE) principles has introduced challenges in translating these principles into measurable outcomes within the construction sector. This study aims to investigate the extent to which circularity principles are embedded within existing sustainability assessment methods for new buildings. The study begins by addressing the interrelationships and distinctions between circularity and sustainability concepts, establishing a foundation for the subsequent analysis. Five internationally recognised sustainability assessment methods for new buildings—BREEAM, DGNB, LEED, Level(s), SBTool—were examined to assess their incorporation of circularity aspects. Each component of these methods was scrutinised for alignment with the 10 circularity strategies outlined in the well-established 10-R framework of waste hierarchy. Expert groups, consisting of CircularB COST Action members, independently evaluated the methods and provided opinions on the direct and indirect associations between the assessed components and the 10-R principles. Disagreements were resolved through group discussions. The analysis revealed varying degrees of integration and explicit reference to circularity principles across the assessed methods. The study also highlighted the subjectivity inherent in identifying correlations and the challenges connected to linking certain circularity-related concepts in the built environment—such as resilience and adaptability—with the 10-R strategies. The findings underscore the need for a more in-depth analysis before making direct comparisons of the integration of circularity principles among different sustainability assessment methods, given their methodological differences. The study also identifies directions for future research.