Flat renovation rules decide more than the look of a kitchen. On 20 May 2025, the fourth-floor slab of a residential building in Kalyan East collapsed through the floors below it, killing six people. Police said they suspected flooring work under way in a fourth-floor flat, allegedly done without permission, and officials said the building had not been on the list of dangerous buildings (PTI, 20 and 21 May 2025). Most renovations carry nothing like that risk. But every contractor's quotation mixes four kinds of work: work that is yours to decide, work your society must approve, work the planning authority must permit, and work nobody may do at all. Sorting the quotation before the first hammer falls is the whole job.
Key takeaways
- Under the model bye-laws most Maharashtra housing societies have adopted, a member needs the committee's previous written permission before making additions or alterations in a flat.
- Outside Greater Mumbai, UDCPR Regulation 1.3 treats cutting into or removing any wall, partition, column, beam or floor as an alteration, which Regulation 2.1.1 forbids without the planning authority's permission; painting, plastering, pointing, paving and retiling are not alterations.
- UDCPR Regulation 9.14(iv) settles a balcony's enclosure at the time of development permission, so enclosing it in a finished building changes the sanctioned plan.
- Cutting into a column, beam or load-bearing wall endangers the whole building, and UDCPR's structural design certificate says the engineer's responsibility ceases once structural members are tampered with.
- The model bye-laws put internal leakage from a toilet or sink on the flat holder, and the promoter's five-year defect liability covers the promoter's work, not your contractor's.
What you need before you start
The sanctioned plan of your building, the reference for every question below; the colours do most of the explaining, as our guide to reading a sanctioned plan shows. The structural drawings, or a structural engineer who has read them, because a sanctioned plan shows rooms, not which walls carry the building. Your society's bye-laws as registered, plus any renovation rules on working hours, lift use, deposits and debris. Your agreement and possession letter: possession starts the promoter's five-year defect liability. And the contractor's scope in writing, item by item.
The steps
1. Break the quotation into separate items
Ask for one line per job: cabinets, wardrobes, bathroom floor, electrical points, any wall, the balcony. What you will see: rooms and a lump sum for "civil work". Red flag: a civil work line nobody will itemise, because that is where demolition hides.
2. Sort each item against the planning rules
Outside Greater Mumbai, Maharashtra builds to the Unified Development Control and Promotion Regulations (UDCPR), which Regulation 1.1 applies to every planning authority except those within Greater Mumbai and a handful of special areas, so they govern a flat in Kalyan-Dombivli, Thane or Pune. Regulation 1.3 defines an addition or alteration widely: "any change in existing authorized building", a change of occupancy, or a structural change, with examples that include adding area or height and "the construction of, cutting into or removal of any wall, partition, column, beam, joist, floor, roof or other support", as well as closing a required way in or out. It excludes gardening, whitewashing, painting, plastering, pointing, paving and retiling. Regulation 2.1.1 forbids alterations without the Authority's permission, and Regulation 2.1.2(vi) exempts safety grills to windows and ventilators.
What you will see: the cosmetic part of a renovation falls on the permitted side. Red flag: the word "partition". The definition names partitions beside columns, so "it is only a partition" does not settle whether the Authority must be asked.
3. Find out which walls carry the building
Take the structural drawings, or a structural engineer, to every wall the contractor wants to move. In some buildings internal walls are infill between columns; in others they are cast in concrete and are the structure, and finished plaster looks the same either way. Red flag: a contractor who answers by knocking on the wall.
This is where most owners realise they have never seen their building's drawings. Your project's free page on ReraGenie shows whether the building plan approval slot on MahaRERA holds a document and when it was uploaded, and lists every document the promoter filed, so you start from the plan the authority stamped rather than the brochure. An upload is not proof of the permission, so open the document.
4. Apply to the society in writing
The model bye-laws require a member to obtain the committee's previous written permission before any additions or alterations in the flat, applied for through the Secretary with the particulars of the work. They allow no structural change without the competent authority's prior permission, and one version adds supervision by a structural engineer from the local authority's panel. The headline changes in the Maharashtra Co-operative Societies (Amendment) Rules, 2026, in force from 30 June 2026, concern charges, and revised model bye-laws were still in draft after objections closed on 27 August 2026, so read your society's registered bye-laws, which govern until it adopts new ones.
In a new building the permission comes from whoever manages it: the society's committee where a society has been registered, the promoter's managing body where it has not, a handover the first twelve months after possession walks through. Red flag: a spoken "go ahead" from a manager. If a written application meets silence, your rights as a society member set out what you may ask for.
5. Get the planning authority's permission for an alteration
Regulation 2.2.1 requires anyone intending to make alterations in a building to apply to the Authority in writing, through a registered architect, town planner or licensed engineer or supervisor, with the prescribed forms, fees and plans. You need both permissions: the bye-laws make the committee's consent a precondition for the member, the regulations make the Authority's a precondition for the work. Red flag: a contractor offering to "manage the corporation" with no architect or licensed engineer named.
6. Protect the waterproofing, and your defect claim
Retiling is outside UDCPR's definition of alteration, but a bathroom floor is also the ceiling of the flat below. Under the model bye-laws' repairs clause, internal leakage from a toilet, sink or similar fitting is the flat holder's cost, with intimation to the society, while leakage from rainwater and external common pipes and drains is the society's. For five years from possession the promoter must put right defects in its own work under section 14(3) of the RERA Act, as our guide to builder liability for defects explains; a crack your contractor's chisel opened is not the promoter's work. Photograph every wet area, dated, before work starts. Red flag: tiles laid straight over broken waterproofing instead of redoing it and holding water on it first. If your keys came before the occupancy certificate, fit-out possession carries risks of its own.
7. Run the work like a neighbour
Keep to the committee's hours and lift rules. Debris leaves the building or sits where the committee says, never on the staircase, in the lift lobby or in a refuge area, which Regulation 1.3 defines as an unenclosed space where occupants gather during an evacuation and Regulation 9.29.6 requires in buildings taller than 24 m. Red flag: rubble on the stairs on day one. The safety rules you can check yourself cover the exits it would block.
The four columns
Sorted, a typical quotation lands like this.
| Allowed without permission | Ask the society in writing first | Needs the planning authority too | Never allowed in a finished flat |
|---|---|---|---|
| Painting, whitewashing, plastering and pointing | Retiling a bathroom or kitchen where the floor bed and its waterproofing are broken | Removing or cutting into any wall or partition, even one that carries no load | Cutting, chipping or coring a column, beam, slab or load-bearing wall |
| Retiling and paving that leave the base alone | Moving a sink, drain, water line or gas point | Adding area or height, or closing a required way in or out | Building anything beyond the outer edge of a balcony |
| Kitchen cabinets and wardrobes fixed to walls, not cut into them | Safety grills to windows, which need no planning permission under Regulation 2.1.2(vi) | Enclosing a balcony into a room after the plan was sanctioned | Enclosing a refuge area, or storing anything in it |
| Loose furniture, and lighting on existing points | Anything fixed to the facade, such as outdoor units | Changing the flat's use, for example to an office | Removing a wall the structural drawings show carries load |
The first column follows UDCPR's own exclusions. The second reads the bye-law clause carefully: work touching shared services, the facade or the flat below is the society's business even where the planning rules are silent. The third is UDCPR's definition of an alteration. The fourth is not waiting for a better permission: Regulation 9.14(v) allows nothing beyond a balcony's outer edge, a refuge area is defined by being unenclosed, and the rest is the frame every flat depends on, whose signatories are on record.
Never let anyone cut a chase into a column or beam for a pipe, core through a beam for an air-conditioner line, or chip a column to set a wardrobe flush. The certificate of structural design adequacy whose format UDCPR prescribes in Appendix C, under the structural engineer's duties at C-4.3, states that the engineer's design responsibility ceases the moment any alteration is made or the structural members are tampered with.
An analogy: clothes and surgery
A flat is closer to a body than to a box. Clothes and haircuts are yours to change whenever you like: paint, tiles, cabinets. Anything that cuts into the body needs a qualified person, a record and consent: a partition coming out, with an architect, the society and the authority each signing. Some things are not done at all, because the body cannot live without them: columns, beams and slabs. Most renovation mistakes are surgery treated as a change of clothes because the contractor called it one.
Meera's quotation
Meera (illustrative, as our stories always are) took the keys of her twelfth-floor 3BHK in a KDMC tower near Dombivli on 30 June 2026: 960 sq ft of carpet area on a Rs 70 lakh loan, with her older Thane flat kept for family visits. Time-poor as ever, she handed the interiors to a contractor a colleague recommended. His quotation had five items: a modular kitchen, wardrobes in all three bedrooms, retiling the second bathroom, knocking down the wall between the living room and the third bedroom, and enclosing the balcony into the living room. Names and numbers in this story are illustrative.
For once she did the reading herself. The kitchen and wardrobes went through, fixed to the walls with the sink and gas point left where they were. The bathroom went in writing to whichever body manages her building, the society's committee if a society has been registered and the promoter's managing body if not, with dated photographs and a condition that the waterproofing be redone and tested before tiling. A leak below would be hers to pay for, and even inside the five years of the promoter's defect liability, a leak her contractor caused would not be the promoter's to fix.
The wall was the snag. The contractor called it a partition; the structural drawings, which she asked the managing body for, showed a concrete wall carrying the floors above, which moved it from the third column of the table to the fourth. The balcony went for a different reason: enclosure is settled at development permission under Regulation 9.14(iv), and doing it now would mean asking KDMC to change the sanctioned plan of a whole tower for one flat. She kept the open balcony, measured as the balcony rules describe, and the quotation lost the two items that would have cost the most to undo.
The scale of the problem in one corporation
In early August 2026, after a building collapse in Bhiwandi, KDMC identified 661 buildings within its limits as unsafe: 204 extremely dangerous, 143 of which were still occupied, and 457 unsafe but repairable.
Source: Free Press Journal, reporting KDMC's survey of unsafe buildings, August 2026
A new tower is nowhere near such a list, and leaving its frame alone helps keep it that way. Older buildings add the periodic structural audit the model bye-laws require, which our guide to structural audits explains.
What the Rs 499 report shows for this
Renovation starts after the purchase, but the documents that decide it were filed before. For one Maharashtra project, ReraGenie's Rs 499 buyer report sets out sanctions, units and sales building by building, so you know which building's sanction your flat sits under. It includes the project's filed documents as a ZIP, among them the building plan approval where the promoter uploaded one, the drawing your architect asks for first. And it closes with what to verify before you book, each fact with its filing date, plus a free 90-day project watch that emails when the filing changes. See what the buyer report covers.
The checklist
- Get the quotation itemised, with no lump sum for civil work.
- Mark each item against UDCPR's definition of alteration.
- Check every wall to be touched against the structural drawings.
- Apply in writing to the committee, or the promoter's managing body where no society exists yet, and keep the answer.
- For any alteration, apply to the planning authority through a registered architect or licensed engineer.
- Photograph wet areas first; have waterproofing redone and tested before tiling.
- Drop anything that cuts the frame, builds beyond a balcony's edge, or encloses a refuge area.
Methodology and sources
- UDCPR, consolidated text as updated 30 January 2025: Regulations 1.1, 1.3, 2.1.1, 2.1.2(vi), 2.2.1, 6.6, 9.14 and 9.29.6, and Appendix C, C-4.3. Regulations 1.3 and 2.1.2 are marked in the text as modified by later clarifications, so confirm the current position with your planning authority.
- Model bye-laws for co-operative housing societies, Maharashtra: the clauses on additions and alterations and on repairs, whose numbers vary between versions; the MCS (Amendment) Rules, 2026 and the 2026 draft revised model bye-laws.
- PTI, 20 and 21 May 2025, on the Kalyan East slab collapse; Free Press Journal, August 2026, on KDMC's unsafe buildings.
This article is educational and not legal advice. For a dispute, consult a lawyer who practices before your state's RERA.
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