The construction industry is one of the largest consumers of natural resources, contributing significantly to global CO₂ emissions and waste generation. To address these environmental and economic challenges, the integration of circular economy principles into real estate development is essential. This thesis investigates how circular principles can be effectively incorporated into project selection processes, particularly in the transformation of existing buildings. The research aims to bridge the gap between circularity and standardized project evaluation methods to enhance sustainability while maintaining economic feasibility.

The study is guided by the central research question: "How can circular principles be integrated into project selection criteria in real estate development?" To address this, three sub-questions explore the principles of circularity, the criteria for project selection, and the development of a structured framework for implementation.

A mixed-method approach was employed, including an extensive literature review, semi-structured expert interviews, and a focus group workshop. The literature review provided insights into existing circular economy frameworks, project selection methodologies, and key drivers and barriers to circularity. Empirical research involved interviews with nine industry experts and a validation workshop with seven professionals, enabling a comprehensive analysis of practical challenges and enablers for circular transformation projects.

Findings highlight that economic feasibility remains a major barrier to circular transformations, with high upfront costs and regulatory constraints limiting adoption. However, tools such as Life Cycle Assessment (LCA), material passports, and digital tracking systems enhance transparency and facilitate informed decision-making. The study also emphasizes the importance of early integration of circularity in project selection, the role of expert knowledge and interdisciplinary collaboration, and the need for corporate cultural shifts to ensure long-term circular adoption.

Based on these insights, this research develops a structured roadmap to systematically embed circular principles into project selection processes. The roadmap aligns circular strategies with key decision-making stages, offering practical recommendations for real estate developers, policymakers, and investors. By balancing economic, environmental, and social objectives, this study contributes to advancing sustainable real estate practices and promoting a shift towards a circular built environment.