Circling Towards Profit: A Circular Life Cycle Approach to Evaluate the Economic and Environmental Feasibility of Buildings and Construction

The concept of Circular Economy (CE) has undergone a significant evolution, extending beyond the traditional 3R paradigm (reduce, reuse, recycle) to embrace a more holistic perspective that incorporates additional aspects. Previous research indicates the profound impact of circularity on the economic as well as the environmental domains of sustainability. Despite numerous efforts to integrate circularity metrics with established environmental and economic evaluation methods, a comprehensive framework that cohesively synthesizes circularity with both economic and environmental in a single unified framework is notably missing. To address this gap, this paper introduces the Cost of Circularity Assessment Tool (CoCAT), an innovative and integrated framework. CoCAT incorporates the Whole Building Circularity Indicator (WBCI) along with Life Cycle Assessment (LCA) and Life Cycle Costing (LCC) to simultaneously evaluate the economic as well as the environmental feasibility of various circular solutions. WBCI serves as the key metric on which the rest of the analysis is developed. The effective integration of WBCI with LCA has previously been demonstrated, and this study extends the methodology to encompass LCC through a rigorous literature review and critical analysis. The paper methodically explains this unified framework, aligning CE-based methodologies for all three assessments within the CoCAT in line with the existing standards. Additionally, it provides guidance on conducting integrated inventory analysis, combined interpretation, and visual representation of results, with a focus on whole-building level assessment. The research reveals that such integration streamlines the assessment process, saving time and effort. CoCAT can be used by stakeholders, companies and LCA practitioners to identify trade-offs between increased circularity and its impacts on sustainability performance (environmental and economic) for informed decision-making.