Digital twin platform for evaluating thermal bridging effects on aggregate thermal performance of prefabricated wall panel systems

Thermal bridging through building envelope systems accounts for 30% of energy loss in both traditional and prefabricated buildings. While the prefabrication industry is rapidly growing, offering numerous advantages over traditional construction, such as reduced time, labor, costs, and CO₂ emissions, thermal bridging in prefabricated wall panel systems remains uninvestigated. To address this research gap, this study developed a digital twin (DT) platform that fuses real-world experimental tests on prefabricated building envelope systems with virtual 3D Multiphysics simulations, enabling a comprehensive, real-time assessment of thermal bridging and aggregate thermal performance measurement of two prefabricated wall panel designs. The developed DT platform integrates data from both virtual simulations and real-world physical environments and allows for a comprehensive assessment of thermal performance across the entire prefabricated wall panel system. This approach provides a more accurate analysis compared to relying solely on spot-specific thermal experimental data or computer simulations that generally overlook potential construction defects observed in the physical environment. The results revealed that optimizing the bracket and connector designs in prefabricated wall panels significantly reduces thermal bridging by an average of 57% in R-value efficiency (i.e., R-5.2) across three different temperatures. Assessment of alternative design scenarios also showed that as insulation levels increase in prefabricated wall panels, the relative impact of thermal bridging becomes even more pronounced. These findings help designers, researchers, and building scientists assess the importance of using a DT platform to fully understand and visualize the 3D effects of thermal bridging on the aggregate thermal performance of building envelope systems, specifically on prefabricated wall systems.