Building Regulations in Mumbai - Building Bye-Laws in Mumbai

Our simple outline of important building regulations in Mumbai...

1. FSI: for residential buildings is 1.33 from South Mumbai till Mahim in the West and Sion in the centre.  North of that it is 1.0.  For educational, healthcare and hospitality projects, it is 1.33 plus 300% extra, which is 1.33 x 4 = 5.32.

The following are not counted in FSI calculations:
• Basements
• Stilt Parking
• Staircases
• Lifts and lift lobby (lobby area to an extent equal to lift area, additional lobby areas are counted)
• Pump rooms, utility areas, security cabins
• Shafts
• Society Office upto 12 m2 if there are less than 20 apartments, and 20 m2 if more
• Gymnasium upto 2% of FSI area
• One Servants’ toilet per floor upto 2.2 m2 with access from lift lobby
• Refuge Areas and terraces
Normally, 15% of the plot must be reserved as a recreation area.  If the plot area is greater than 2,500m2, then this 15% is also subtracted from the total FSI of the plot. Note that this explanation pre-dates the concept of "Fungible FSI". We will add an explanation of fungible FSI soon.

What is FSI? FSI or floor space index, is the ratio of how much space you may construct on a given plot. It is the ratio of allowed built-up area to the plot area.  For example, on a 10,000 ft2 plot with an FSI of 2, you may construct 20,000 ft2 of area.

2. TDR: can be an additional 1 on FSI in normal areas, not in CRZ areas.  Areas given to road setbacks and recreational grounds (15% of the plot area) should be deducted from the TDR.  Therefore, if there are no setbacks, the TDR will be 0.85.

What is TDR? Transferable Development Rights are a mechanism to reduce new construction in crowded areas and shift it to less dense parts of the city. In Mumbai, TDR was initiated to de-congest south Mumbai and shift new construction northwards. It works as follows: say you own a 10,000 ft2 plot with an FSI of 1.3 in South Mumbai, and your building has 8,000 ft2 of built-up area. To utilise your full FSI allowance, you would have to build 10,000 x 1.3 = 13,0000 ft2 of space. This means you have 5,000 ft2 of extra capacity in your plot which you are not using. With TDR you can then sell this right to build 5,000 ft2 to someone north of you. You then cannot build more than the existing 8,000 ft2 on your plot.

3. Height of Building: depends on location and proximity to airport.  Height of a room should be less than 4.2m.

4. Setbacks / Open Spaces Required around building: Ht/3 for living spaces (bedrooms, living rooms) and Ht/5 for dead walls and toilets.  This can be overcome by paying a premium to the BMC.  However the CFO will demand a clear 6mx6m for fire engine movement.

5. Min Size of Rooms: as follows: 
  
                                       Min Area                Min Width
Habitable Rooms              9.5 m2                       2.4m
Toilets                              2.2 m2
Toilets (separate)             1.1 m2 (WC)            1.5 m2 (area of bath)
Kitchens (1 BHK Flats)      5.5 m2                       1.8m
Kitchens (2 BHK Flats)      7.5 m2                       2.1m

6. Balconies: upto 10% of the FSI area per floor allowed free of FSI.  Flower beds upto 1.2m in width allowed all around the building.  If a flower bed is placed in front of a balcony, then its width should not exceed 0.6m.

7. Refuge Areas: one every 24m in height, area not less than 4% of the occupied space existing till the next refuge area.

8. Staircases: not less than two if the floor plate is more than 500m2 or the height more than 24m.  Each should be 1.5m wide, enclosed by a 230mm brick wall, ventilated to the outside, and accessed via a fire door.  Higher buildings will require 2m stairs.

9. Shafts: min dimension of 0.6m.

10. Service Floors: should have a minimum clear height of 1.5m.

11. Parking: 

In residential buildings, for tenements upto 70 m2 in area, 1 car per tenement, 2 for bigger flats (except in A Ward, where 4 are required).  After this, add 10% for visitors. (50% of spaces can may be 4.5 x 2.3m, the rest not less than 5.5 x 2.5m). 

In educational buildings, it is one car per every 35m2 of carpet area of the administrative offices and public services spaces only.


Disclaimer: this is intended to be a guide for students and laymen, and is a partial guide to building regulations in Mumbai.  These regulations also change from time to time.  Consult your licensed architects and permissions experts before building anything!