Examining Low-Carbon Material Initiatives: Existing Policies, Impacts on the Procurement of Projects, Current Challenges, and Potential Solutions to Reduce Embodied Carbon in the Construction Industry

Given the reinforced expectations of a carbon-constrained future and to address carbon dioxide (CO2) emissions from construction materials, the construction industry has been seeking solutions for proactive climate change mitigation and adaptation measures. Since more than 30% of all concrete materials in the United States (US) are procured by federal, state, and local governments, public procurement is an important mechanism that could be used for decarbonizing concrete and reducing its negative impacts. Therefore, many initiatives and policies have been introduced to reduce the carbon footprint of construction materials by considering sustainable or green procurement practices in construction projects. Despite that some policies have been introduced in different United States, there remain gaps in the goals, scope, and stipulations of these policies and barriers to the associated mass adoption by the industry/market; which hinders the applicability and effectiveness of these policies. Since these policies are considered to be relatively new as they were just introduced in the previous five years or so, there is a scarcity of research works on low-carbon construction material legislations and a lack of guidance, knowledge, training, and education on the requirements of these policies. Also, these policies differ from one jurisdiction to the other. Therefore, by following a mixed-approach methodology based on review of previous literature as well as existing bills and policies, case study analysis of 8 projects, and semistructured interviews conducted with 16 experts, this paper examined low-carbon concrete legislations by analyzing existing policies and initiatives, studying their impacts on the contractual relationships and procurement of construction projects, identifying current challenges associated with these legislations and programs, and proposing potential solutions. The paper's results and findings offer insights into the current state of low-carbon concrete legislations, the different policies and initiatives that could potentially solve or address the urgent issue of embodied carbon in the construction sector, the needed key policy elements, the contractual relationships that could be used in low-carbon projects, and the challenges that still persist in current initiatives and that need to be addressed in the future. Ultimately, this paper educates practitioners and researchers on the different contractual and legal aspects related to low-carbon materials and adds to the body of knowledge by laying the foundation for developing a framework or program for low-carbon construction materials that takes advantage of the knowledge gathered in this topic as well as the identified challenges in the paper. This will help jurisdictions in developing better initiatives, policies, and legislations to efficiently reduce embodied carbon in the built environment, and ultimately promoting sustainable procurement practices as well as green procurement measures in the construction sector.