Life Cycle Assessment of Building Deconstruction: Insights from Ten Projects

In 2018, the United States generated more than 600 million tons of construction and demolition (C&D) waste, of which 143 million tons were landfilled. Demolition alone accounted for 94% of this total. In Pittsburgh, nearly 1,700 condemned properties are slated for removal, representing a substantial source of future waste. While the U.S. Environmental Protection Agency estimates that 90-95% of C&D waste could be recycled or reused, demolition practices rarely realize this potential. Deconstruction-carefully dismantling buildings for material recovery-has the potential to reduce landfill waste, conserve resources, and lower embodied carbon. Although life cycle assessments (LCA) have been applied to deconstruction, most focus on single projects or specific materials, limiting their broader relevance. To address this gap, we conducted a standardized LCA (ISO 14040/44) study on ten documented deconstruction projects using publicly available data. Three scenarios-standard, good, and best practice- were modeled with varying salvage rates to quantify material recovery and associated greenhouse gas emissions reductions. A sensitivity analysis of transport distance to test the influence of transportation distance assumptions was also included to strengthen decision-making insights. The results show that across 10 projects on average, good deconstruction scenarios reduce emissions by approximately 62%, while best-practice scenarios achieve average reductions of about 86%, with several projects reaching 98-99% reductions relative to the standard scenario. These reductions are primarily driven by avoided impacts from virgin material production associated with material recovery and reuse. Beyond environmental benefits, salvaged materials expand access to affordable, low-carbon building supplies and support healthier communities. By comparing the results across multiple cases and contexts, this study provides robust evidence for decision-makers, municipalities, and designers on how deconstruction can support circular economy transitions and sustainable material strategies worldwide.