Abstract
As a systems-oriented value-maximization-based framework, Circular Economy (CE) has been increasingly recognized as a promising tool for enhancing sustainability in various engineering fields but appears rarely discussed in the U.S. built environment. While significant efforts are invested to improve the sustainability of U.S. built environment, the construction sector remains one of the largest resource consumers, energy users, and waste producers. This research contributes to furthering the body of knowledge on how to integrate the CE paradigm with existing building and construction ecology measures for improving the sustainability of the built environment in the U.S. in order to mitigate the ongoing climate crisis. Case studies have been created to investigate the status quo and potential opportunities of adopting CE within the construction ecology in order to enhance sustainability efforts. As the cutting edge, the sustainability rating systems issued by the U.S. Green Building Council and the International Living Future Institute are taken to represent theoretical achievements in construction sustainability; therefore, these rating systems are the focus of two case studies. The research questions are answered with a better understanding of sustainability and CE practices in the U.S. built environment during different proposed circular lifecycle stages. This research provides insights to different managers and decision makers for integrating CE paradigm into sustainability practices.