Introduction
Quite simply, the construction professionals are quite familiar with the abbreviation FSI, which stands for Floor Space Index. Floor Area Ratio (FAR), otherwise known as FSI and Floor Ratio, is a legal mechanism that balances urbanization with green developments, enabling the expansion of urban centers in a sustainable manner.
How is FSI used in Construction?
FSI for a plot means how much space can be constructed on the particular piece of land. In other words, how much space one can build while taking into consideration land use policies and the density of the area in which the land is located. Rural areas usually have a lesser FSI as compared to urban areas as the space is restricted.
Friends of FSI
- Floor Area Ratio – This term is used in the US with an acronym as FAR which describes a ratio between the floor area and the total area of the site.
- Floor Space Ratio – This term is used in Australia with the acronym of FSR which describes the total space available to be constructed in relation to the total land area.
- Plot Ratio – This term is mostly used in the UK in defining the amount of square footage that a plot can practically accommodate.
FSI Formula and Calculation
The formula used in the calculation of FSI is the same as with the use of FAR with the exception to how it is formulated.
Formula
[ \text{FSI} = \left( \frac{\text{Total Floor Area of all Floors of the Building}}{\text{Plot Area}} \right) \times 100 ]
Example Calculation
Let us assume there is a 1000 square foot plot that has been constructed with a total area for all the two floors which is 2000 square feet.
- FAR: ( \frac{2000}{1000} = 2 )
- FSI: ( 2 \times 100 = 200% )
With a FAR of 2, it is possible to construct a building with up to 200% to a land area of the specified size in this instance.
Differences between FAR and FSI
| Aspect | FAR (Floor Area Ratio) | FSI (Floor Space Index) |
|---|---|---|
| Definition | Total of Floor area to Land Area ratio | Similar to FAR but in percentage terms |
| Units | A dimensionless decimal e.g. 2.0 | A percentage e.g. 200 percent |
| Common Usage | United States and few regions | India and few other regions |
| Legal Implications | Zoning code regulation | The regulation impacts what development occurs |
FSI/FAR in Major Indian Cities
| City | FSI/FAR values available |
|---|---|
| Bangalore | 1.75 to 3.35 |
| Chennai | Between 1.5 to 2.0 |
| Delhi | Between 1.2 to 3.5 for slums; CRUD 4 |
| Gurgaon | Between 1 to 1.45; 1.25 for ind. |
| Ahmedabad | Between 1.2 to 1.8 |
| Pune | 1.5 to 2.5 or 4 or 5.5 for slums |
| Mumbai | Island city 1.33 suburb 1.0 to 1.5 |
| Hyderabad | No cap with an average between 6 & 7 |
| Kolkata | FSI 1.5 to 2.5/ plots depending |
Importance of FSI
A significant factor in encouraging vertical expansion, enhancing the quality of land use, and advancing ecological solutions to urban density is high FSI values.
Having a high FSI encourages the construction of mixed use structures which not only stimulates growth but also shortens the commuting hours and improves the efficiency of public infrastructure.
Conclusion
Grasping the concepts of FSI and FAR are key to appropriate planning in cities. They help enhance the aesthetics and functionality of structures in a city by assisting in achieving an economically viable city while able to take into account the constraints of the surroundings and the infrastructure present. As urbanization increases, FSI and FAR will dictate how the sky lines of the cities in India will look like for more years to come.
Frequently Asked Questions
What does FSI mean in real estate?
FSI is a metric that determines how much area is allowed to be built on a piece of land in relation to the area of that land in accordance with zoning laws of the area.
FSI: How do you compute it?
The area of the plot is divided by the overall area of the building. The result can be provided either as a percentage or a ratio.
What does 2.5 FSI stand for?
It stands for the maximum allowable constructed area, which can be 2.5 times larger than that of the land.
Get more information Dream Location