Impact of windows on the indoor thermal environment of Chinese Chuandou-style timber residential houses: Tests and simulations

Model tests and simulations were conducted to investigate the influence of windows on the thermal environment of Chinese Chuandou-style timber residential houses. Besides, the thermal comfort of the house was also analyzed. The test results indicated that the measured temperature curves have obvious five-stage characteristics. The air temperature in the attic during the daytime was higher than that in the room, especially when the windows were open. During the daytime, when the windows were closed, the indoor air temperature was higher than the outdoor air temperature, while when the windows were fully open, the opposite pattern was observed. Numerical simulations showed that increasing the window–wall ratio could lead to an increase in indoor air temperature during the daytime, and decreasing the window width–height ratio would slightly reduce the indoor air temperature. The window opening degree has a significant impact on the indoor thermal environment, the higher the window opening degree, the lower the indoor air temperature during the daytime. Further, reducing the window heat transfer coefficient could also lead to a slight increase in indoor air temperature. The thermal comfort of the house was poor during the daytime in summer, but it was slightly improved when the windows were open.