A Bengaluru buyer in 2026 loved a spacious flat on the top floor of a small apartment building, priced a little below the market. What she did not do was compare the building she was standing in with the plan the civic body had actually sanctioned. That plan showed one floor fewer. The floor she was buying, and two others, had been added beyond the approval. When she applied for a home loan, the bank's valuer flagged the deviation and the loan fell through, and the wider building faced the risk of a notice. The extra floor that made the flat affordable was exactly what made it unsafe to buy.

The short answer. A sanctioned plan is the civic body's approval of exactly what may be built, in floors, floor area and use. When the actual building differs, through extra floors, excess floor area, reduced setbacks, converted parking or a changed use, the deviation can block the occupancy certificate, invite demolition or penalty, complicate utility connections and stop a home loan. The trade-off buyers miss is stark: a deviated flat can look bigger or cheaper, but the deviation transfers a serious legal and financial risk onto whoever buys it.

What is a sanctioned plan and what counts as a deviation?

The sanctioned plan is the civic body's formal approval of what can legally be constructed on a plot, setting the permitted floors, the floor area ratio and the use. A deviation is any material difference between that approved plan and the building as it actually stands. Common deviations include an extra floor that was never approved, built up area beyond the permitted floor area ratio, setbacks reduced below the required open space around the building, parking space converted into rooms or shops, and a change from the approved use. Some very small differences may fall within a permissible tolerance or be capable of regularisation on payment, but larger deviations sit outside what the rules allow and carry the real risks. The only way to know which you are facing is to compare the actual building against the sanctioned plan.

This is a check most buyers never make, because the building looks finished and lived in, and the plan sits in a file they never ask to see. Yet the plan is the document that decides whether the structure is authorised. A flat can be beautiful, occupied and for sale, and still be part of a building that the record never permitted in that form.

Why is a deviated building risky to buy?

Because the deviation follows the property, and the buyer inherits every consequence of it. A building with major deviations in floor area, height, setbacks or use can be refused an occupancy certificate until it is regularised, and without an occupancy certificate the building is treated as unauthorised for occupation. That single gap cascades: banks may refuse a home loan, water, sewerage and permanent electricity connections can be difficult to obtain or remain on a temporary footing, and resale, registration and any future regularisation become harder. In the worst cases, the civic body can act against the unauthorised portion. None of this is the seller's problem once you have paid, it is yours, which is exactly why the check belongs before payment.

The uncomfortable truth is that the discount on a deviated flat is often the deviation itself being priced in. The extra floor, the converted parking or the excess area that makes the flat seem like good value is the very thing that carries the risk. A price that looks too good on a top floor flat, in particular, is worth pausing over, because unauthorised upper floors are among the most common deviations.

How do you check for deviations before buying?

You obtain the sanctioned plan and compare it, carefully, against the building as it stands. Ask the seller or builder for the approved plan and the occupancy certificate, and check the number of floors, the built area, the setbacks and the use against what you can see and measure on site. Because reading a plan against a real structure is a technical exercise, this is a check worth doing with an architect or civil engineer who can spot an excess floor, a shrunken setback or a converted space that a buyer would miss. A plain overview of the approvals every Bengaluru owner should know sets out what these documents are. The occupancy certificate is a particularly useful signal, because a building that could not get one is telling you something.

If the seller cannot produce the sanctioned plan and the occupancy certificate, treat that as a finding in itself. A compliant building has these documents and can show them. Reluctance or vagueness about them is often the first sign of a deviation the seller would rather you did not measure.

Can a deviation ever be fixed?

Sometimes, but you should never buy on the assumption that it will be. Small deviations within a permissible tolerance may be acceptable, and some larger ones can be regularised on payment under whatever scheme and limits apply at the time, but regularisation is neither automatic nor guaranteed, and the rules around it change and are sometimes contested. Relying on a future regularisation to cure a deviation is a gamble, because if it does not come through, you are left owning an unauthorised structure with all the problems that brings. The safe approach is to buy a building that already complies, or to make any purchase strictly conditional on the deviation being resolved, in writing and on the record, before you pay.

Let the seller carry the burden of any fix, not you. If a deviation genuinely can be regularised, the seller can do it before the sale and prove it. Paying first and hoping to regularise later simply moves a risk that was theirs onto your shoulders, at exactly the moment you have the least leverage to insist on anything.

How does this fit with your occupancy certificate checks?

The deviation check and the occupancy certificate check are two sides of the same question: is this building authorised as it stands. A building free of major deviations is one that can obtain an occupancy certificate, and our guide to the difference between an occupancy certificate and a completion certificate explains why that document matters so much. Both sit within the wider due diligence set out in our guide to verifying a property title in Bengaluru. Read the plan, confirm the certificate, and check the title, and you have covered whether the structure is authorised, occupiable and cleanly owned.

The common thread is that appearances mislead. A lived in flat looks authorised, an occupied building looks complete, and a confident seller looks trustworthy, yet only the documents, checked against the reality, confirm any of it. Doing that checking is the difference between buying a home and buying a problem that photographs well.

What are the seven steps to check for building deviations?

Work through these before you pay.

1. Ask the seller or builder for the sanctioned building plan and the occupancy certificate.
2. Count the floors in the building and compare them against the approved plan.
3. Check the built area, setbacks and use against what the plan permits.
4. Engage an architect or civil engineer to compare the plan with the actual structure.
5. Treat a missing sanctioned plan or occupancy certificate as a warning sign.
6. Do not rely on a promised future regularisation to cure a deviation.
7. Make any purchase conditional on deviations being resolved before payment.

Is a cheaper deviated flat ever worth it?

Only rarely, and never without going in with your eyes fully open. A deviated flat at a lower price can occasionally suit a cash buyer who understands that a loan, a clean occupancy certificate and an easy resale may all be out of reach, and who accepts the risk of action against the building. That is a narrow and risky position, and for the ordinary buyer who needs a loan and wants a secure home, it is not worth it. The apparent saving is the priced in risk, and it tends to be collected later, at the loan desk, the utility office, or the resale that will not close. The reliable rule is to buy a building that matches its sanctioned plan, and to treat any deviation as a problem to be solved by the seller before you pay, not a discount to be enjoyed.

Frequently asked questions

What is a building plan deviation? A deviation is a material difference between the civic body's sanctioned plan and the building as built. Common examples include extra floors, built area beyond the permitted floor area ratio, reduced setbacks, parking converted into rooms, and a changed use. Small differences may fall within tolerance, but larger deviations sit outside the rules and carry serious risk.

Why is buying a deviated flat risky? Because the deviation follows the property. A building with major deviations can be refused an occupancy certificate, and without one it is treated as unauthorised for occupation. Banks may refuse a home loan, utility connections can be difficult, resale becomes harder, and the civic body may act against the unauthorised portion. These consequences become yours once you pay.

How do I check for deviations before buying? Get the sanctioned plan and the occupancy certificate, and compare the approved floors, built area, setbacks and use against the actual building, ideally with an architect or civil engineer. If the seller cannot produce the sanctioned plan or the occupancy certificate, treat that as a warning sign. A compliant building has these documents and can readily show them.

Can a deviation be regularised later? Sometimes, on payment and within the limits of whatever scheme applies, but it is neither automatic nor guaranteed, and the rules change. Never buy on the assumption that a deviation will be cured later, because if it is not, you own an unauthorised structure. Require the seller to resolve any deviation, in writing, before you pay.

Last updated 2026-08-28. PropNewz Team.