###### Abstract  
The concept of circular economy (CE) has emerged as an effective strategy for addressing resource depletion, waste generation, and environmental challenges, offering a promising path towards a more sustainable future. In the building sector, adopting CE principles can significantly mitigate environmental impacts, minimize lifecycle costs, and promote sustainability throughout a building's lifecycle. Using a mixed-method approach via a pre-interview questionnaire and semi-structured interviews with 10 sustainability experts, this study analyses the significance of 15 CE strategies in building construction projects, assessing their importance and ranking their potential for adoption. Furthermore, this study evaluates the feasibility of applying CE principles to different building types, including storage, industrial, commercial, residential, business, and healthcare facilities. The role of lifecycle stages including initiation and planning, design, procurement, construction, operation and maintenance, and end of life is examined to identify phases with the highest potential for successfully embracing CE principles. The role of stakeholders in driving change is also analyzed. The outcomes of this study reveal that the most feasible strategies include the use of renewable energy, design for durability and longevity, prefabrication, and offsite construction. The study findings indicate that storage, industrial, and business (office) buildings are the most feasible for CE application, while the initiation and planning and design stages are identified as critical phases for embracing CE adoption. Owners and designers emerge as the stakeholders with the greatest influence on CE implementation. The results of this study provide a comprehensive overview of the feasibility of CE adoption in the building sector. These findings offer valuable insights that can inform the development of targeted strategies to support the effective adoption of CE principles. c 2025 15 1174 122  
processes that have dominated the construction industry for decades [5] only involve one direction of movement whereby raw materials transform into products that end up as waste after their service life. Globally, the construction industry involving building and infrastructure projects produces more than 10 billion tons of construction and demolition waste every year [6]. Around 10-15% of those building materials are wasted during construction [7], and many materials are discarded rather than reused or recycled at the end of their life. Only 20-30% of these materials are recycled or reused at the end-of-life phase [8]. A major obstacle to sustainable progress in the building sector is the substantial CO\({}_{2}\) emissions generated by the dependence on non-renewable energy sources during the planning, construction, and operation of buildings [9]. By 2050, construction activities are projected to account for nearly half of the total emissions associated with new buildings, a significant increase from the current contribution of 28% [10]. According to the Global Alliance for Buildings and Construction (GlobalABC) [11], the share of renewable energy in the building sector has only increased by 0.9% since 2015, reaching 5.9% in 2022, far below the target of 11%. If this trend persists, the renewable share will reach just 7% by 2030. To align with climate targets, the share of renewable energy needs to grow by 1.5 percentage points annually until 2030 [11]. The Ellen MacArthur Foundation [7] highlights that 20-40% of the energy used in existing buildings can be profitably conserved through enhanced efficiency measures and sustainable approaches. The concept of Circular Economy (CE) has gained widespread attention as an innovative economic model aimed at decoupling economic growth from the reliance on finite resource consumption. It represents an alternative to the current linear economy of'make-use-dispose'. According to [PERSON] et al.