Roof of traditional houses in southern China

Northwest China has a dry climate, less precipitation and a flat roof. Generally, it is only necessary to spread a woven reed mat, rice straw or corn straw on the rafters, spread a layer of mud on it, then spread a layer of dry soil, and finally smooth it with wheat straw mixed with mud. Although Ningxia also uses tiles, it only raises tiles instead of tiles. This kind of house is not waterproof. The roof is flat like a platform. Corn, peppers, etc. can be dried on the roof, which is called "barn" locally. Tarim basin and Turpan area in Xinjiang are extremely dry, with many sunny days and few rainy days. The average annual precipitation is less than 50 mm, and the sun is like fire during the day and cold at night. The top of the residential building is plastered with mud to form a platform, the thickness of which is more than 1 ft, which can not only reduce the heat penetration into the room, but also be used for insolating food; The thickness of the mud wall around the house is also above 1 m; The foundation of the house is dug a foot or two underground to prevent hot air from entering the room. In addition, a large number of grapes and poplars are planted around the homestead and in the courtyard. One is shading, which can also block the heat wave from entering the room and lower the room temperature. The climate in the south is warm and humid, and there is a lot of rain, so the roof of the house is built high and the roof slope is large. In this way, the area irradiated by the hot sun can be reduced in summer, and too much hot air will not be introduced into the room; In addition, the steep roof is beneficial to rainwater drainage and reduces the impact of rainwater on the roof tile surface. For example, the bamboo houses of Dai, Lahu, Wa and Jingpo nationalities in Yunnan are very distinctive. It belongs to tropical monsoon climate, hot and humid. Bamboo buildings mostly use roofs leaning on mountains with steep slopes of 45 ~ 50. The lower part is ventilated overhead to isolate moisture, and there is a fire pool indoors to drive away rheumatism. In tropical cities with high temperature and rainy weather, many streets are lined with pedestrian corridors (commonly known as arcades), such as Xiamen, Shantou, Guangzhou, Nanning and Taiwan Province Province. The shops and buildings on both sides of the street extend from the second floor to the sidewalk, forming a long "corridor" This kind of pedestrian corridor, under the condition of tropical rainfall, can not only prevent pedestrians from being exposed to direct sunlight, but also solve the problem of rain shelter. The same is true of the wind and rain bridges and covered bridges of the Dong nationality in the border areas of Hunan, Guangxi and Guizhou.