The ratio of the floor area of a plot to its size is called the Floor Area Ratio. For instance the FAR of 2.0 can be applied to a 1000 sq. ft. lot, and the maximum FAR on the lot, according to local building regulations, is 2,000 sq. ft. The allowed FAR is based on zoning, plot size, road width, setbacks and development regulations.

Local rules may vary. The FAR is prescribed for various categories of plots in Delhi, for instance, FAR of 200 to 350 for various categories of plots in Delhi. DDA Master Plan for Delhi 2021

What Is Floor Area Ratio (FAR)?

FAR means the ratio of the total floor area of a building to the building’s plot area. It is used by planning authorities to control the level of development on a site.

Depending on the area any one of the following terms can be used: Floor Space Index (FSI) or Floor Space Ratio (FSR). The way specific spaces are counted, however, may vary depending on local regulations.

FAR can be useful for a property owner to consider as a first step to determining what development potential a plot has. It still needs to be taken into account in conjunction with setbacks, parking, height clearance, fire safety and land use.

FAR Meaning in Practical Terms

The higher the FAR the more floor area can be built on the same lot. The smaller the FAR the more restrictive it is on the total size of the building.

Consider a 1,000 sq. ft. plot. For a FAR of 1.5, the allowable floor area would be 1,500 sq. ft. for a FAR of 3.0, it would be 3,000 sq. ft.

This does not imply that it’s easy to simply put the whole permitted area in any sort of preferred form. The final building design must satisfy other planning requirements.

Floor Area Ratio Formula:

The basic formula for floor area ratio is:

FAR = Total Floor Area ÷ Plot Area

The maximum floor area can be estimated by:

Permitted Floor Area = Plot Area × Permissible FAR

Both measurements must be in the same unit. If area of the plot is in square meter, then the floor area should also be in square meter.

This calculation provides a planning estimate. The actual permissible construction depends on the rules applicable to the specific property.

Simple FAR Calculation Examples

The following table shows how the calculation works for different plot sizes and FAR values.

Plot Area	FAR	Permitted Floor Area
100 sq. m.	1.5	150 sq. m.
200 sq. m.	2.0	400 sq. m.
300 sq. m.	2.5	750 sq. m.
500 sq. m.	3.0	1,500 sq. m.

For a floor area ratio calculation example, take a 240 sq. m. plot with a FAR of 2.25. Multiplying 240 by 2.25 gives 540 sq. m. of permitted floor area under the basic calculation.

If you are learning how to calculate floor area ratio, a floor area ratio calculator follows the same principle. It uses the plot area and applicable FAR to estimate the permitted floor area. It should be treated as a planning aid rather than a substitute for checking local regulations.

Read more: Autodesk BIM 360 Software Guide

FAR vs Building Height

The total floor area is regulated by FAR and the height of a building is regulated by building height. The two are linked but aren’t synonymous.

Potential options for distribution of the permitted floor area may vary depending on the height limit, setbacks, floor-to-floor height, road width, fire safety requirements, and zoning provisions.

For this reason, FAR alone cannot be used to determine the exact number of floors possible on a plot.

What Counts in FAR — and What Usually Doesn’t

The areas included in FAR are not identical across all cities. Some spaces may be counted fully, counted partly, or excluded under specific conditions.

Usually Counted	May Be Exempt, Subject to Local Rules
Habitable floor areas	Basement or stilt parking
Internal corridors and lobbies	Staircases and lift shafts within permitted limits
Commercial and office areas	Certain service rooms
Some balcony areas	Ducts and specified service spaces

These categories are only indicative. The relevant development authority should be consulted before using an exemption in a project calculation.

Typical FAR Ranges in Indian Cities (Indicative)

There is no single FAR applicable across Indian cities. The permitted value can change according to land use, development density, road width, plot characteristics, and the local master plan or zoning regulations.

Development Type	Indicative FAR Range
Low-density residential	1.0–1.5
Medium-density residential	1.5–2.5
High-density residential	2.5–4.0
Commercial	3.0–5.0+

These figures are indicative ranges rather than universal approval limits. Local regulations should always take priority. For instance, in Delhi, FAR is mentioned to be 200 – 350, depending on the plot size, for residential provisions.

Read more: ISO 19650 Standard Guide

What is premium far?

Premium FAR is additional development potential that may be allowed above the base FAR, provided certain conditions are met and charges are paid.

For instance, if the base FAR is 2 then an extra FAR of 0.5 is approved, the total FAR is raised to 2.5. There are other FAR which are available, eligible and charged based on the planning authority.

In addition to premium floor area ratio, the owner of a property should review notification, zoning requirements, road width, and payment requirements. Additional FAR does not remove other restrictions on building design.

The Direct Impact of FAR on Buildings

Affects the amount of floor area that can be planned on a site directly as FAR. The reason for this is that the higher the allowed FAR, the more development can take place on the same property and the lower the FAR, the more it restricts the floor area.

It also has an impact on the arrangement of the building, parking needs, movements, structure, services and open space. These factors need to work together during planning.

For owners and designers, FAR is therefore one important planning parameter, not a standalone measure of how much a property can accommodate.

Read more: What is RIBA Framework

FAR and Construction Cost Relationship

The higher the FAR, the more space will be involved in the construction, but it does not directly mean the higher the project’s cost. Other factors that affect expenses include structural system, materials, finishes, services, site conditions, labor and project specifications.

A greater amount of floor area could necessitate further structural support, vertical movement, plumbing, electrical and fire-safety measures. All of these requirements can add to the project cost.

A more beneficial method is to consider permitted floor area in conjunction with construction cost, site restrictions, proposed use, and approval criteria. This provides a better understanding of the potential for development and its feasibility.

Frequently Asked Questions

1. What is the meaning of FAR?

FAR is the expression of Floor Area Ratio. It is a ratio of the total built-up area of the building to the area of the plot.

2. What does FAR 2.5 mean?

Generally, the allowed floor area is 2.5 times the plot area for FAR 2.5. So under the basic calculation, a 1,000 sq. ft. plot would be equivalent to 2,500 sq. ft.

3. What does FAR 1.25 mean?

The general rule for FAR 1.25 is that the number of square feet of your floor area can be 1.25 times the plot area. This would be 1250 sq. ft. under the base formula for a plot of 1000 sq. ft.

4. What’s the difference between FAR and FSR?

FAR and FSR generally describe the ratio between total floor area and plot area. The terms used are dependent on planning authority or region.

5. Does FAR include a balcony?

The balcony can be totally included, partially included or excluded as per local building regulations, size and type of development.

6. What does FAR 200 refer to?

It typically represents 200% or two times the plot area. Under a simple calculation, a 100 sq. m plot would be equivalent to 200 sq. m floor area.

7. What does FAR 2.0 mean?

In general, FAR 2.0 is considered to allow for double plot area. For example, 500 sq. m. would equal 1,000 sq. m.

8. In real estate, what does FAR stand for?

FAR is the Floor Area Ratio in the field of real estate. It is a ratio of the allowable floor area to plot area.

9. Is basement included in FAR?

The treatment of basements varies from region to region and one treatment is different from the other depending on its use. Other basement areas may be counted, but parking or service areas may not be.

10. What is permissible FAR?

Permissible FAR is the maximum FAR allowed according to the relevant planning and building regulations for a property. It may be influenced by the size of the plot, land use, road width and zoning.

11. What is Premium FAR?

Premium FAR is additional development potential that may be available under specified conditions and applicable charges. It is available in the local regulations.

12. How many floors will I be able to construct if I have a FAR of 2.25?

There is no specific number of floors in FAR 2.25. Other factors which can influence the possible number of floors include height limitations, setback, floor to floor heights, parking requirements, fire-safety considerations, and local development regulations.

13. Can FAR change after I buy a property?

FAR may be adjusted when the responsible authority updates its development regulations, zoning requirements or planning controls. It is important for property owners to review rules at the time of planning or construction.

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