Research on the Carbon Emissions and Costs Between Prefabricated and Traditional Cast In Situ Buildings Based on BIM

An integrated building information model (BIM) was constructed based on embodied carbon emissions (CEs) and a cost assessment framework to evaluate the environmental and economic performance of prefabricated buildings (PBs) and traditional cast in situ buildings (TBs) during the materialization stage. BIMs and carbon emission factor (CEF) methods were combined to quantify material consumption, embodied CEs, and construction costs under identical building conditions. An eight-story residential shear wall structure was selected as a case study, and carbon was analyzed across different stages. Sensitivity and uncertainty analyses were incorporated to evaluate the robustness of the accounting results under different transportation, electricity emission, and regional production scenarios. The results indicated that prefabricated construction exhibited lower embodied carbon emissions and improved economic performance compared with traditional cast in situ construction. The material production stage was identified as the dominant carbon source, while electricity-related emission factors had the strongest influence on the accounting results. The proposed framework provides a transferable methodological pathway for low-carbon building assessment and sustainable decision making in prefabricated residential construction.