Comparative Environmental Assessment of High Material Recovery Deconstruction and Conventional Demolition: A Pre-Demolition Audit Case Study

While construction and demolition waste (CDW) remains one of the largest waste streams and a major source of environmental impacts worldwide, strategies based on circular economy principles, selective deconstruction, and pre-demolition audits (PDAs) have been increasingly promoted to mitigate these impacts. This study presents a comparative life cycle assessment (LCA) of high material recovery deconstruction and conventional demolition of an administrative building in Czechia. Two end-of-life (EoL) scenarios were evaluated: a Circular scenario derived from detailed PDA data and real material flows, and a Business-as-usual (BAU) demolition scenario representing conventional demolition practice. The system boundary included EoL stage (modules C2–C4) and module D in accordance with EN 15804+A2. Environmental modelling was conducted in SimaPro software V.9.2. using the ecoinvent 3.7 database and covered nine environmental impact categories. Results show that circular deconstruction consistently yielded higher environmental benefits, with improvements ranging from 1% to almost 15% across the assessed categories. Recycling of aluminium, steel, and glass contributed most significantly to avoided impacts, while concrete recycling provided benefits mainly under high-quality recovery pathways. The study demonstrates the value of PDA as an effective decision-support tool to improve material recovery and support more sustainable CDW management.