The windows of the quadrangle are all on the front of the house, facing the yard, and there are only windows in the yard. Even if some houses have windows to ventilate outside the yard, they are relatively high and small.
The windows and sill walls decorated by Chinese quadrangles are generally inlaid with large frames between the upper sill or some left and right columns, so that the upper fan can be erected generally, while the design of the lower fan is fixed. If you stick windows in winter, you usually use Korean paper or some cellophane. From the outside, it is very dark, which can not only avoid the cold outside the courtyard, but also keep the indoor light sufficient.
In summer, in the decoration of quadrangles, gauze or cold cloth must be used to paste windows. The window screens made of cloth for the decoration of quadrangles in northern counties look like cloth, but they are not cloth. It can be ventilated to avoid indoor overheating.
You can add a piece of paper to the cool cloth outside, roll it up during the day and put it down at night, so it is also called rolling window. Some people use quadrangular windows with upper branches and lower branches. In winter or spring in Beijing, because there are many sandstorms, residential buildings use door curtains, and ordinary people need to hang plywood in winter.