Circular Design and Embodied Carbon in Living Buildings: The Missing Potential

Abstract

While the built environment negatively contributes to resource use, waste generation, and climate change, this same sector has the potential to provide innovative solutions to these complex global challenges. Circular economy (CE) strategies have the potential to provide these solutions, yet systems and incentives related to CE and the built environment are disparate and at varying stages of development. Green building rating systems, such as the Living Building Challenge, have the potential to change the market and drive innovation, but these systems need to evolve and change in alignment with the emergence of new and promising strategies, such as CE. The objective of this study was to elucidate whether implementing CE practices could help further reduce embodied carbon and life cycle carbon dioxide equivalent (CO2-eq.) emissions in buildings that are already environmentally conscious to further drive market innovation. This study analyzed the potential reduction in the embodied carbon of an existing Living Building, the Frick Environmental Center, by applying various CE strategies and using life cycle assessment. The investigated strategies include (1) using materials that are biodegradable and have lower embodied carbon, (2) using salvaged alternatives for embodied carbon-intensive building products, (3) extending the lifespan of selected building materials, and (4) carbon sequestration. Given that the case study building is already LEED Platinum and Living Building certified, the results elucidated the extent of potential environmental impact savings in buildings that are already certified due to having lower environmental impacts than the industry average. The CE strategies resulted in a 30% reduction in the building’s embodied carbon (excluding end-of-life) compared with the base case. Results exemplify whether a significant decrease in the buildings’ embodied carbon/life cycle CO2-eq. emissions can be achieved as a result of implementing modest changes in design.