Is the space under the stairs on the first floor a pool area?

Generally speaking, all the stairs are, not just the first floor.

The pool area is a part of the building area. The height less than 2.2 meters is not counted as the construction area. Therefore, the space under the stairs is not a building area, nor is it a pool area (even if it is sufficient locally).

The pool area mainly includes:

1, elevator shaft, pipeline shaft, stairwell, garbage chute, power distribution room, equipment room, public hall, aisle, basement, guard room on duty, * * * own house, and management room serving the whole building.

2. The partition wall between the suite (unit) and the public building space is half of the horizontal projection area of the external wall (including gables).

Extended data:

The laws and regulations regulating the sales area and allocation area of commercial housing mainly include the Rules for the Calculation of Sales Area of Commercial Housing and the Allocation of Public Building Area (Trial) issued by the Ministry of Construction and the Interim Provisions for the Calculation of Sales Area of Commercial Housing and the Allocation of Public Building Area in Beijing issued on September 26th, 2000. Among them, Beijing's regulations clarify the principle of sharing public building area, the public building area that can be shared and the public building area that should not be shared. The distribution principle is as follows:

(1) The public area of commercial housing is shared by buildings. The shared public building area is the public building area in this building, and the public building area that is not connected with this building shall not be shared into this building;

(2) The public building area serving the whole commercial house is shared by all commercial houses in the building; The public building area within a local scope is shared by the beneficiary commercial housing;

(3) After sharing the public building area, the specific parts of the shared building area of each commercial house will not be divided, but no one may occupy or change the original design function.

Baidu Encyclopedia-Shared Building Area