Mumbai moves to curb floor space index misuse

By Madhav Mallya, Vidhii Partners

In January, the Maharashtra government amended certain provisions of the Development Control Regulations for Greater Mumbai, 1991, which define the calculation of floor space index (FSI). One of the aims of this amendment was to deal with builders that were including certain areas such as flower beds, niches, and balconies (previously excluded from the computation of FSI) as the carpet area of a flat or workspace and therefore violating FSI limits.

Floor space index is defined under the Maharashtra Regional and Town Planning Act as the ratio of the combined gross floor area to the total area of the plot. Regulation 35 of the Development Control Regulations for Greater Mumbai lays down the computation of floor space index for residential, commercial and industrial zones.

The amendment

Prior to this amendment, the regulations had no express provision indicating areas falling within the ambit of FSI. Regulation 35(2) states that certain areas cannot be included in FSI. These include areas such as those covered by staircase rooms, lift rooms above the topmost storeys, areas covered by staircases, areas of the basement used exclusively for parking and other ancillary uses, the office room of a co-operative society, lofts, areas covered by electrical substations, fire chutes and balconies.

Madhav Mallya Associate Vidhii Partners
Madhav Mallya
Vidhii Partners

Such areas are included as a part of “super built-up” areas in agreements to sell residential or commercial space. The prevalent practice has been for builders to charge for this “super built up” area for the purpose of recovering costs. However, a builder did not have to pay premium on such areas to the government as they were not taken into account for calculating FSI.

Following this amendment, the areas of balconies, a letter box room, one public telephone booth, garages on ground level required for parking, etc., which earlier were expressly not included in the calculation of FSI now are to be included within the purview of FSI. In addition to the above areas, flower beds, voids, fire escape balconies, niches below window sills, covered swimming pools, etc., which were wrongfully being included in FSI by builders, are now to be calculated as FSI, and builders will be charged premium on the construction of such areas.

The state government via the same resolution introduced the concept of compensatory floor space index, in regulation 35(4), permitting a builder to exceed the current FSI limits by special permission. A compensatory floor space index may be permitted, up to 35% for residential development and 20% for industrial/commercial development. The builder will be charged a premium at 60%, 80% and 100% of the stamp duty ready reckoner rate, for residential, industrial and commercial development respectively.

On payment of a premium, builders have an option of providing amenities such as balconies, flower beds, niches, public telephone rooms, etc., without sacrificing the actual carpet area of a flat or workspace. The amendment also excludes all parking spaces from the computation of FSI (except for areas covered by parking garages on ground level) and allows for additional parking to the extent of 25% without payment of premium, which will encourage builders to make better use of space.

It is important to note that the amendment continues to exclude certain necessary amenities such as fire chutes, a fitness centre, refuge areas, area of a basement used for parking and other facilities, cornices or weather shades from the purview of FSI.

Effects of the changes

The amendment has reduced the level of ambiguity which earlier existed when it came to the calculation of FSI. There is now greater clarity when it comes to understanding which areas are included for the purpose of calculating FSI limits. An obligation of greater transparency is imposed on builders, which cannot misuse certain areas to increase carpet area or super built up area without paying a premium on the additional construction.

Builders may now use compensatory FSI to increase carpet area, which is essential in a highly populated city such as Mumbai. When looked at from this perspective, compensatory FSI is a boon in that it will provide a larger and more comfortable home or working space.

A question which arises is whether the use of compensatory FSI to increase carpet area will lead to a decrease of open spaces and green spaces, which are already scarce and come at a premium in Mumbai. While the city needs more living space, it also needs less congestion and more green cover.

The amendment, though welcome and beneficial to the government, builders and buyers alike, could come at a cost.

Madhav Mallya is an associate at Vidhii Partners and can be reached at



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