Decarbonization, Dematerialization, and Economic Gains in Circular Economy for Construction and Demolition Waste Management in Europe.

Construction and demolition waste (CDW) offers opportunities for decarbonization, dematerialization, and economic gains through high-value-added circular management. Yet, most of this material is downcycled. This study assesses different CDW circularity strategies in the EU27 + 4 from 2010 to 2050. Results show that continuing current trends in waste management could reduce cumulative carbon emissions by ∼2 Gt CO2-eq, material use by ∼24 Gt, and costs by ∼€680 billion compared with virgin material use. Implementing advanced circularity measures could further reduce emissions by 38-48%, material use by 7-8%, and costs by 21%. Germany, the UK, France, and Italy contribute over 70% of these benefits due to their large building stocks. While metals represent only 6% of CDW mass, they drive up to 90% of decarbonization and economic value; minerals enable over 70% of dematerialization across all scenarios. Clean energy transitions may reduce circular economy's carbon advantage as primary production also decarbonizes. Coordinated policies integrating data, technology, incentives, and holistic targets are essential to realize systemic circularity.