According to the Unified Standard for Civil Building Design (GB50352-20 19) and the data of Zhihu, the overhead floor of residential area refers to the open space floor with structural support and no external wall. Under normal circumstances, the overhead floor is located below the first floor, which is low in height and transparent on all sides, and is often used for parking and other functions. The setting of overhead floor is mainly to prevent the wall from being damaged by tiny uneven settlement of foundation, and at the same time, it can also increase the activity space of the community. In the field of real estate, the overhead floor is mainly used for high-rise buildings, especially residential areas with dense houses and high plot ratio. By setting the overhead floor, the green area and public area can be increased and the target balance can be achieved.