Buyers comparing two flats usually argue about carpet area and rarely about what the law actually requires a room to be. It is worth knowing, because on the question most people assume is settled, the code says nothing at all.
Key takeaways
- Regulation 9.2.1 leaves the size and dimension of a habitable room to the requirement and convenience of the owner. There is no minimum floor area for a bedroom.
- Regulation 9.3.1 says the same about the kitchen.
- The code does fix height: 2.75 m minimum for a habitable room and a kitchen, and 2.1 m for a bathroom or water closet.
- It fixes the bathroom: 1.00 m by 1.20 m independent, 0.9 m by 0.9 m for a water closet, or 1.50 sq m combined with a minimum width of 1.00 m.
- And it fixes light: openings of not less than one tenth of the floor area, with no part of a room more than 7.5 m from its opening assumed to be lit.
- So the guarantee is about air, light and headroom rather than about floor space.
The provision that is not there
Chapter 9, Regulation 9.2.1, UDCPR as updated 30 January 2025 is one sentence long: the size and dimension of habitable rooms shall be as per the requirement and convenience of the owner.
Chapter 9, Regulation 9.3, Kitchen repeats it for the cooking space. The size of a kitchen, or of a cooking alcove serving as cooking space, shall be as per the requirement and convenience of the owner.
The word doing the work there is "owner", and at the design stage the owner is the developer, not you. A code that leaves room size to the owner's convenience is a code that has decided not to set a floor at all, which is why flats in the same city and the same price band can have bedrooms of very different sizes and both be entirely compliant.
This is the opposite of what most buyers assume, and it changes what a site visit is for. There is no legal minimum to check a bedroom against. There is only the plan, the tape measure and the price per square foot, which is why the carpet area figure in your agreement carries the weight it does.
What the code does fix
| What | The minimum UDCPR sets |
|---|---|
| Height of a habitable room | 2.75 m, measured to the lowest point of the ceiling, with a maximum of 4.5 m for a flat roof |
| Height of a kitchen | 2.75 m, measured from the floor to the bottom of the slab, except where a floor trap from above intrudes |
| Height of a bathroom or water closet | 2.1 m |
| Independent bathroom | 1.00 m by 1.20 m |
| Independent water closet | 0.9 m by 0.9 m |
| Combined bathroom and water closet | 1.50 sq m, with a minimum width of 1.00 m |
Those heights come from Chapter 9, Regulation 9.2.2, Height of Habitable Rooms, and the row above is the common case rather than the whole rule. Table 9-A sets a minimum and a maximum for every occupancy, and three of its qualifications matter to anyone planning to check a flat with a tape measure. An air-conditioned habitable room may be 2.4 m, not 2.75 m. The minimum head-way under any beam is 2.4 m, so a soffit lower than the rest of the ceiling is not by itself a defect. Under a pitched roof the 2.75 m is an average, with 2.0 m permitted at the lowest point, and 2.6 m average for EWS or LIG housing.
The maximum is the part almost nobody expects. A habitable room under a flat roof may not exceed 4.5 m, and where a particular occupancy genuinely requires more height than the table allows, that extra height is not counted towards FSI. So a tall room is not a developer giving away saleable area, and a room that measures 2.4 m under a beam is not a developer cutting a corner. Both are the table working as written.
Notice the shape of that list. The rooms with a fixed minimum size are the small wet ones, where a dimension below a certain point stops being usable at all. The rooms you live in are left open, and the code protects them a different way.
Chapter 9, Regulation 9.4 adds three requirements to every bathroom and water closet: it must be situated so that it derives ventilation from a ventilation shaft or external air, it must have a window or ventilator opening to a shaft or open space of not less than 0.3 sq m with a side of not less than 0.3 m, and its sewerage outlet must connect to the sewerage system, or to a septic tank within the plot where no system exists.
The real guarantee is light and air
Chapter 9, Regulation 9.20, UDCPR as updated 30 January 2025 is where the code protects habitability, and it does so as a ratio rather than as a size.
Banded by the provision
- Openings in habitable rooms and kitchensMinimum aggregate area, excluding doors, of not less than one tenth of the floor area of the room
- Depth from the openingNo portion of a room more than 7.5 m from the opening is assumed to be lighted. Greater depth is permitted only with a proportionate increase in the opening.
- Kitchen openingAn opening of 1.0 sq m is treated as adequate
- Bathroom, water closet or storeAn opening of 0.30 sq m with one dimension of 0.30 m is treated as adequate
- StaircaseAdequately lit and ventilated where openings on the external wall total not less than 1.0 sq m per landing
Source: Chapter 9, Regulation 9.20.1, UDCPR as updated 30 January 2025
The one tenth rule is the most useful thing in this article for someone holding a floor plan. A 12 sq m bedroom needs at least 1.2 sq m of opening excluding the door. A larger room needs proportionately more, so window area is not a design flourish; it scales with the room by regulation.
The 7.5 m rule is the second. A room may be deeper than 7.5 m, but the portion beyond that distance is not assumed to be lit, and the extra depth has to be paid for with a proportionate increase in opening area. Long thin rooms and deep living-and-dining runs are exactly where this bites.
The shaft your bathroom opens onto
Where a water closet or bathroom does not open onto the front, side, rear or interior open space, it must open onto a ventilation shaft, and Chapter 9, Regulation 9.20.2, Ventilation Shaft sizes that shaft by the height of the building.
| Height of building | Cross section of the shaft | Minimum one dimension |
|---|---|---|
| Up to 10 m | 1.2 sq m | 0.9 m |
| Up to 12 m | 2.4 sq m | 1.2 m |
| Up to 18 m | 4.0 sq m | 1.5 m |
| Up to 24 m | 5.4 sq m | 1.8 m |
| Up to 30 m | 8.0 sq m | 2.4 m |
| Above 30 m | 9.0 sq m | 3.0 m |
Above 30.0 m the regulation requires a mechanical ventilation system in addition to the shaft, which is a recognition that a vertical shaft alone stops working as buildings get tall.
The larger habitable rooms have their own version of this in Chapter 6, Regulation 6.9, Interior and Exterior chowk*, which sizes interior and exterior chowks. An interior chowk must be at least 3.0 m by 3.0 m, and not less than the square of one sixth of the height of the highest wall abutting it. An exterior chowk must be at least 2.4 m wide, and the sentence to remember is the disqualifier: if it is narrower than 2.4 m it is treated as a notch and is not considered for deriving ventilation at all.
Names and numbers in this story are illustrative. When Priya and Arjun compared two Pune flats with the same quoted carpet area, the difference that decided it was not the floor plan. It was that in one, the second bedroom's window opened onto a gap between towers that measured under 2.4 m, so on the sanctioned plan it was a notch rather than a chowk, and the room derived its ventilation from elsewhere.
That is the sort of thing a drawing shows and a brochure does not. If a window looks onto a narrow slot, ask what it is marked as on the plan.
What to check before you sign
- Stop looking for a minimum room size, because there isn't one, and price the flat on measured carpet area instead.
- Check ceiling height against 2.75 m for habitable rooms and the kitchen, and 2.1 m for bathrooms, remembering that 2.4 m is compliant in an air-conditioned room and under a beam.
- Measure the window against one tenth of the room's floor area, excluding the door.
- Look for any room deeper than 7.5 m from its window, and ask what the opening was increased to.
- Ask what narrow gaps beside your windows are marked as, since an exterior chowk under 2.4 m wide does not count as ventilation.
Where the filings come in
None of these dimensions are in the public register. MahaRERA records buildings, floors and unit counts, and the carpet area field in the data is empty on every project, so room level questions are answered by the sanctioned plan and by your agreement, both of which you are entitled to.
What the register does show, free, is the project's own account of itself: the filed land area, the buildings and their floors, the promoter's extensions with the reasons given, the certifying architect and engineer, and any complaints or litigation with case numbers. It is readable at reragenie.com without an account.
ReraGenie's buyer report, Rs 499, reads one project's full filing and the documents behind it, sets the promoter's record against the rest of the register, compares the possession slip with the median for the same pincode, and states plainly what the filings do not contain, which on questions like this is the honest answer. It includes a project watch for 90 days.
For what is measured inside the flat, see balcony, loft, cupboard and mezzanine, and for why a window may face a wall at all, the margin rules.
Source: Unified Development Control and Promotion Regulations for Maharashtra, UDCPR as updated 30 January 2025. Sanctioned under the Maharashtra Regional and Town Planning Act, 1966.
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