As urbanization continues to surge, building materials are poised to become a dominant contributor to global emissions. Traditionally, the building sector has focused on mitigating “operational carbon” linked to a building's day-to-day energy needs, such as heating, cooling, lighting, and equipment usage. However, there has been a paucity of studies on the environmental impacts associated with building materials across a building life cycle. This paper addresses this gap by conducting a life cycle assessment of housing stocks in two diverse case studies: Montreal (Canada) and Lima (Peru). These cities offer a North/South perspective, highlighting the challenges, opportunities, and potential solutions for decarbonizing the housing sector. The study investigates the potential of circular strategies and investigates three scenarios: selective deconstruction (allowing for reuse and recyc...