How to calculate building area with floor area ratio

The calculation method of floor area ratio is floor area ratio = total building area above ground ÷ usable land area.

First, calculate the attention

If the ground floor of the building is used as a passage, public parking, greening and decoration, residents' leisure and supporting facilities, the height of the overhead floor should be between 2.8 meters and 3.6 meters, and its construction area is not included in the plot ratio.

At the top of the building, there are stairwells, water tank rooms, elevator machine rooms, structure (equipment pipes) transfer floors, ground floor garages, utility rooms, etc. If the storey height is more than 2.2m, it will be included in the plot ratio according to the total area; if the storey height is less than 2.2m, it will be included in the plot ratio according to the area of 1/2.

The balcony of a building, whether it is concave balcony, overhanging balcony, closed balcony or unsealed balcony, is calculated according to half of its horizontal projection area. When the depth exceeds 1.8m, all kinds of balconies are included in the floor area ratio according to the whole area.

The part where the ceiling elevation of the semi-basement exceeds the outdoor terrace elevation 1.0m is included in the calculated value of the above-ground construction area; Less than 1.0 m, not included in the plot ratio.

When the elevation of the outdoor floor of the building is inconsistent, the elevation of the nearest urban road in the surrounding area shall prevail, and 0.2m shall be added as the outdoor floor, which shall be verified according to the above provisions.

Second, the building density calculation formula

Building density = sum of basement areas of buildings/planned construction land area, for example, a piece of land is 10000 square meters, of which the ground construction area is 3000 square meters, and the building density of this land is 3000/ 10000=30%. Generally, the building density will not exceed 40%-50%, and roads, greening, squares, parking lots, etc. need to be reserved for land in some areas.

Influence of Building Floor Area Ratio on Housing

1, high population density.

Although the floor area ratio refers to the proportion of the construction area to the total area, the construction area will affect the number of residents, so from the size of the floor area ratio, buyers can judge the population density of a community.

A house with a high plot ratio will definitely bring a high density of residents. In the case of overpopulation, the living comfort of the community will decline and the privacy will not be so good. Therefore, property buyers should pay attention to this when buying high-density residential areas.

2. Poor internal planning

Areas with high plot ratio are mostly used for building houses, and other supporting businesses are less, such as green spaces and public areas.

Less greening and small public activity area will affect the living environment and quality of residential areas. Another possibility is that the distance between buildings is too close and the roads in the community are narrow, which will adversely affect the lighting and ventilation conditions of houses.

3. Security is more difficult.

When the plot ratio of the community is relatively large, there will be more residents, so there will be more people entering and leaving the community at ordinary times, and the probability of outsiders mixing in will increase accordingly, which will increase the security risks.

Therefore, it is more difficult to manage the residential area with large plot ratio, especially in the public security area, which puts forward higher requirements for the security system of high plot ratio residential buildings, and is also a test for property companies. More patrol personnel need to be arranged to ensure the safety of residents.