Circular Economy Strategies in Densification and Refurbishment of Residential Buildings – State of Application and Future Directions

The fast population and economic growth put tremendous pressure on the planet’s resources. In this context, the building sector is recognized as one of the most significant contributors to greenhouse gas emissions and the use of raw materials. The Circular Economy (CE) is expected to contribute to a reduction of waste landfills, extraction of raw materials, and greenhouse gas emissions. This study aims to understand to what degree and how CE strategies can be applied to the refurbishment and densification of residential buildings. Using a qualitative approach, this study examines the application of CE strategies in the building sector through five semi-structured expert interviews. The literature identifies five CE principles for buildings: building in layers, designing-out waste, designing for adaptability and flexibility, designing for disassembly, and selecting materials. From the interviews, designing-out waste was the most common approach for refurbishment and densification of residential buildings. Nevertheless, the implementation of CE strategies within the building sector is still limited and challenging due to various barriers and little encouragement. More stimuli from governments through regulations and guidelines, increased collaboration between stakeholders, and technological advancements are expected to reduce the obstacles to implementing CE strategies in refurbishment and densification.