Study on Outdoor Thermal Comfort of Commercial and Residential Mixed-Use Blocks in Hot and Humid Climates: Taking Guangzhou, China as an Example

This study evaluated outdoor thermal comfort in commercial and residential mixed-use blocks in hot and humid climates. A subjective survey questionnaire examined thermal environment metrics, individual data, and 141 pedestrian responses. The findings indicated that the average air temperature (31.8 °C) and relative humidity (65.8%) of the four mixed-use blocks were considerably high. The thermal environment differed between each block owing to the influence of block texture and building form. In addition, subjective sensation scores differed among the blocks, aligning with subjective preferences, though subjective acceptability remained largely within a “neutral” range across all blocks. The relationship between thermal environment and subjective perception was intricate, as their patterns of variation were not merely characterized by simple positive or negative correlations but were influenced by a multitude of factors. Multiple linear regression analysis indicated that air temperature, relative humidity, and mean radiant temperature were crucial factors affecting subjective acceptability, all demonstrating statistical significance at p-value < 0.05. Furthermore, this study examined the effect of morphological features on thermal comfort, identifying texture density, street height-to-width ratio (D/H), and orientation strategy as significant factors. The research provides valuable insights into outdoor thermal comfort in mixed-use blocks and provides recommendations for enhancing thermal environment management.