This study examines the life cycle environmental impacts of different insulation materials used in residential buildings in Vancouver, with a particular focus on the A1-A4 stages —raw material extraction(A1), transportation to manufacturing (A2), manufacturing processes(A3), and transport to the construction site(A4). Under the CleanBC mandate to reduce greenhouse gas emissions by 40% by 2030, addressing both operational carbon (B1-B6) and embodied carbon (A1-A5) is crucial, particularly as embodied carbon is becoming a larger portion of total lifecycle emissions. This shift occurs because operational carbon can be reduced incrementally each year through improvements in building mechanical system efficiency. As a result, focusing on reducing embodied carbon during the design and construction phases is essential to achieving long-term sustainability goals in building lifecycle assessments.

Through a comparative analysis of insulation materials sourced from the United States and Europe, this study examines their Global Warming Potential (GWP), Ozone Depletion Potential (ODP), and Acidification Potential (AP) using Life Cycle Assessment (LCA), such as Athena Impact Estimator, openLCA. The findings indicate that U.S.-sourced insulation materials, such as rock wool and cellulose, generally exhibit lower environmental impacts across most metrics in the A1-A4 stages compared to European materials. U.S.-sourced cellulose consistently shows reduced GWP, ODP, and AP, making it a more sustainable choice for Canadian building applications.

However, European materials demonstrate advantages in Ozone Depletion Potential (ODP) in certain cases, highlighting the significant influence of regional production and transportation processes on environmental performance. The insights from this study offer a valuable basis for architects, engineers, and policymakers to make informed material sourcing decisions, thereby contributing to the broader goals of decarbonization and sustainable construction in Canada.