FSI is the abbreviation of Floor Space Index. This term is the most used in India. It is equivalent to the floor area ratio (FAR) and the floor space ratio (FSR) that are used in other countries.
The floor space index (FSI) basically indicates the maximum permitted floor area that can be built on a plot. Numerically, FSI is the relationship between the covered area of the building floor and the available gross area in that plot / lot.
The allowed value of the Floor Space Index (FSI) varies from one place to another. It also depends on the type of building. The value of the FSI ratio of a specific area is easily found in all the statutes of several cities and municipalities. Different cities or municipalities may have different statutes and, consequently, different FSI values.
The FSI / FAR allowable value depends on
1.Size of the plot
2.Type of building (residential, business, commercial institution, worship, etc.).
3.The width of the adjacent road.
4. Availability of power, water and sewer lines.
For a city or country, the value of FSI / FAR can be revised from time to time depending on the growth of each city, the increase in the value of the land, the development of the energy, water and sewerage facilities.