Buildings, Vol. 16, Pages 2755: Rethinking Climatic Adaptation for Residential Building Energy Efficiency: Cross-Regional Comparative Analysis for Envelope Insulation in China

Buildings, Vol. 16, Pages 2755: Rethinking Climatic Adaptation for Residential Building Energy Efficiency: Cross-Regional Comparative Analysis for Envelope Insulation in China

Buildings doi: 10.3390/buildings16142755

Authors:
Yang Yang
Junhui Zou
Zhineng Jin
Yiheng Liu
Qianru Yang

Envelope-parameter optimization for residential buildings is strongly climate-dependent, yet previous studies have mainly focused on single parameters or specific regions, limiting cross-climate comparison of parameter priorities. This study establishes a unified DeST-based residential building model to compare the effects of external wall insulation thickness and external surface solar absorptivity on heating load, cooling load, annual total load, and operational carbon emissions across five representative climate zones in China. Yinchuan, Beijing, Chengdu, Guangzhou, and Kunming were selected as case cities. Single-factor analysis, two-parameter coupling analysis, supplementary sensitivity analysis, and load-to-carbon translation were conducted under consistent building prototypes, operating boundaries, and evaluation indices. The results show that the effects of the two parameters differ markedly across climate zones, reflecting a transition in parameter dominance under different heating–cooling load structures. Over the tested ranges, insulation thickness changes annual total load by up to approximately 10%, whereas solar absorptivity changes it by only 0.17–1.91%. Mechanistically, insulation reduces winter heat loss but may suppress summer heat dissipation, while solar absorptivity directly affects exterior-surface solar heat gains. Further carbon analysis shows that load-optimal configurations do not necessarily correspond to carbon-optimal configurations. These findings provide quantitative support for climate-adaptive and low-carbon envelope design.