Towards climate-resilient overheating standards for cold-climate residences in China: Insights from large-scale thermal comfort monitoring

Climate change and urban overheating are intensifying summer thermal risks in naturally ventilated residences in China’s severe cold and cold regions, where tailored overheating criteria remain absent. A multi-city 2024 field campaign (>15,000 records; 15,055 valid pairs) integrated indoor and outdoor monitoring with daily thermal sensation to examine the contextual validity of CIBSE TM59 and to calibrate a regional adaptive assessment. More than half of the monitored living rooms—and virtually all bedrooms—were classified as overheated by TM59, while occupants’ sensations showed about 80% agreement. Fixed bedroom thresholds systematically overestimated overheating at night, particularly just above 26 ℃; responses indicate higher acceptability around 26–27 ℃ and perceptual shifts near 28–30 ℃. Building on these findings, a summer residential adaptive model calibrated with the 2024 dataset delivers slightly higher overall classification accuracy and a more balanced sensitivity-specificity profile than GB/T 50785 and a prior preliminary model, while maintaining comparability with international adaptive frameworks. ΔT-based error analyses further suggest a better-calibrated upper-temperature threshold. The results demonstrate the utility of large-scale field evidence for validating and refining overheating assessments and provide a data-driven pathway to localise international guidance. The calibrated thresholds and night‑time bedroom references offer actionable inputs for updating Chinese standards and informing retrofit, ventilation, and passive-cooling strategies that enhance climate resilience in cold-climate residences.