Carbon-saving benefits of various end-of-life strategies for different types of building structures

Against the backdrop of advocating for ultra-low energy consumption buildings both domestically and internationally, much attention has been attracted to energy consumption and carbon emissions at the end-of-life (EoL) stage from the whole life cycle of buildings. Recycling construction and demolition wastes (C&DW) is an inevitable step in achieving the goals of ultra-low energy consumption and “carbon neutrality.” In this paper, the life cycle assessment (LCA) theory was employed to study the carbon-saving benefits of four different EoL strategies (i.e., recycling, remanufacturing, reuse, and the integrated strategy) for various building structures (including frame, frame shear wall, shear wall, and light steel structures), in which the carbon-saving potential (CSP) was served as the evaluation index. The results show that compared with the traditional demolition and landfill disposal methods, the implementation of integrated management strategies for structural buildings in this study can reduce carbon emissions by 150.7–246.8 kgCO2-e/m2, with the carbon-savings of 11.9–34.8 times the carbon emissions generated by abandoned landfill. Among the four structures, the light steel structure has the greatest CSP, reaching (73.75–77.24%), followed by the frame shear wall structure (42.67–46.93%), the frame structure (41.19–45.11%), and the shear wall structure (39.00–43.79%). When the building life span is 50 years, all CSPs of the four structural buildings significantly increased, at this point, deconstruction of the building is the most reasonable approach.