Under normal circumstances, if the basement is used as a garage and equipment room, its construction area is not included in the floor area ratio, and if it is used as a room for commercial services, markets, culture and entertainment, sports, etc., its construction area will be included in the floor area ratio after being converted by a coefficient of 0.6.

For example, the well-known basement parking spaces are not actually included in the floor area ratio.

Paragraph (2) of Article 34 of the Measures for the Administration of Land Value-added Tax Liquidation in Xiamen (Announcement No.7 of Xiamen Local Taxation Bureau No.2016) stipulates that "for the same liquidation project, all the amount paid for obtaining the land use right can be allocated to the saleable building area that is included in the plot ratio, and the amount paid for obtaining the land use right is not calculated for underground parking spaces, civil air defense projects, overhead floors and transfer floors that do not include the plot ratio".

Extended data

The floor area ratio is an important index to measure the intensity of construction land use. The value of plot ratio is a dimensionless ratio, usually the plot area is 1, and the multiple of the total construction area of buildings on the land to the plot area is the value of plot ratio. Accessory buildings are also included, except those which should be marked as not counting the area. It is worth noting that the lower the floor area ratio, the higher the comfort of residents, and vice versa.

Generally speaking, it refers to the ratio of the total construction area of various buildings above the ground to the base area within a certain base. The underground floor area ratio can be calculated according to the planning and management needs.

In fact, it has always been stipulated by the local government itself, and whether the basement is a floor area ratio and whether the underground commercial building (commercial building) is a floor area ratio has been well explored. Not counting the plot ratio is to save land and encourage the development of underground space. Counting the plot ratio is to standardize the real estate market and prevent bad real estate developers from having loopholes. The floor area ratio will be directly related to the size of construction land.

References:

Baidu encyclopedia-floor area ratio