Ask any experienced buyer in Chennai what they check first, and many will mention approvals before anything else. A flat can look finished, have a good location and come with a convincing sales pitch, yet still rest on a building that was never approved or was built differently from its plan. The Chennai Metropolitan Development Authority, usually called CMDA, is the body that approves most planned development in the metropolitan area, and its approvals decide what can legally be built and how the building must look.
This guide explains what a CMDA approval covers, how it differs from related permissions and certificates, and how a buyer can read the paperwork without needing to be an architect. It is written for people who are buying a flat or house and want to confirm that the building is what the plan says it is. The checks described here are general, and the exact documents in any case depend on the project, the survey number and the stage of construction.
What a CMDA approval actually covers
A CMDA approval is a permission given by the authority for development within the Chennai Metropolitan Area. It typically covers the layout of land into plots and roads, the building plan for a particular structure and the conditions that go with it. These conditions may include setbacks from the boundary, the height and number of floors, the built-up area permitted, parking space, open space and the provision of drainage and water connections.
The approval is tied to a specific plot and a specific plan. It is not a general licence for the developer to build whatever suits the market. If the construction departs from the approved drawings in a way that matters, the building may be in breach of the approval even if the flat itself looks fine from inside.
Planning permission and building approval are not the same
Buyers often hear the words planning permission, building approval and layout approval used as if they meant the same thing. They are related but distinct. A layout approval covers the division of land into plots and the roads, drains and open spaces that serve them. Planning permission usually refers to the approval of the land use and the development concept. A building approval is the detailed sanction for constructing a particular building on a plot.
Ask the seller or developer which of these they hold for your project. A project may have a valid layout approval but a building approval for only part of the structure, or a building approval that has since expired. Each permission should match the stage of construction and the phase you are buying into.
Layout approval: the step before the building
Many apartment projects and house plots in the outer areas of the city are first approved as layouts. The layout shows the sub-division of land, the access roads, the drains, the common areas and the reserved sites for public use. Without a valid layout, the plot may not have a proper legal access road, and the common amenities that a buyer expects may not be properly assured.
Check that the layout number on the plan matches the number on the sale agreement and the title documents. If a layout has been revised, ask for the latest approved version and confirm that your plot or flat is shown on it. A plot that is shown differently on the layout and on the deed can cause a long dispute later.
Reading an approved plan without an architect
An approved plan carries the authority’s stamp and reference, the plot details and the drawings of each floor. You do not need to be an architect to read the basics. Find your floor and flat on the plan, and check the built-up area, the number of bedrooms and the balcony or terrace sizes. Look at the position of the staircase, the lift and the fire exit. Check the parking layout and the position of the water tank and septic tank if they are shown.
Compare the plan with the physical building and with the brochure. If the brochure shows a larger flat, a bigger balcony or an extra room that the plan does not show, ask why. The approved plan is the document the authority will rely on, so it is the one you should trust.
Pay attention to the area terms used on the plan and in the sale papers. Carpet area is the usable floor space inside the flat’s walls, excluding the thickness of the walls and the balcony. Built-up area includes the walls and some shared spaces, and super built-up area adds further common areas. A flat advertised with a large built-up figure may have a much smaller carpet area, which changes the price per usable square foot. Under the real estate law, the carpet area is the figure that matters most for the sale, so compare the carpet area on the plan with the figure in your agreement before you calculate anything.
Deviations, extra floors and why they matter
The most serious problems usually come from deviations. A builder may add an extra floor, enclose a balcony, shift a wall or move the staircase without updating the approval. Some deviations are small, but others change the built-up area, the setbacks or the parking requirements. An unapproved floor can be ordered down or regularised later, and a buyer may face a loss of value or a delay in getting the completion certificate.
Look for signs of deviation during site visits. Measure the building’s height against the number of floors shown on the plan. Compare the position of windows and balconies with the drawings. Ask the builder or seller for a written statement that the construction matches the approval, and ask whether any regularisation has been applied for or granted.
A checklist of documents to see
The table below lists the main documents to ask for and what each one tells you. Some documents will be held by the developer and some by the authority, so ask for copies of what the developer holds and check the rest through the proper office.
| Document | What it shows | Who usually holds it |
|---|---|---|
| Layout approval | Plots, roads, drains and reserved spaces | Developer, with the authority’s record |
| Building approval | Sanctioned plan and conditions for the structure | Developer, with the authority’s record |
| Approved plan copy | Floor-wise layout of your flat and common areas | Developer, with a copy for the buyer |
| Completion certificate | Confirms construction matches the approved plan | Authority, issued after inspection |
| Occupancy certificate | Permits use of the building as a residence | Authority or local body, as applicable |
| Title and encumbrance records | Ownership chain and any pending charges | Sub-registrar office and seller |
Completion and occupancy certificates
A completion certificate is issued after the authority has inspected the building and confirmed that construction matches the approved plan. An occupancy certificate permits the building to be used for residence. Some buyers treat these as formalities, but they are important. Without them, the utility connections may be delayed, the society may be unable to register properly and loans may be harder to obtain.
Ask for the certificate numbers and dates. For an under-construction flat, ask the developer for a timeline for these certificates. For a resale flat, ask for copies of the certificates held by the seller and confirm that they relate to the same building and survey number.
Approvals outside the metropolitan limits
Not every plot near Chennai falls under the same authority. Areas outside the metropolitan area are usually governed by the Directorate of Town and Country Planning or a local planning body, depending on the location. The approval process and the document names can differ, so do not assume that the same checks apply everywhere. Confirm the planning authority for the exact survey number and ask to see the approval issued by that authority.
Also check whether the land was converted from agricultural use. A plot that has not been properly converted may not be eligible for construction, and the conversion record should be part of your title file.
What to do if the approval is missing or unclear
If you cannot see a valid approval, stop and ask for a written explanation. A missing approval is not always fatal. Some projects have applied for approval, some have approvals in a different name or for a different phase, and some have revised plans. A clear, documented answer is necessary before any further payment. Do not pay a large amount on the basis of a verbal assurance.
Consider taking a qualified architect or a property lawyer to check the plan and the approvals before you sign. The fee is small compared with the cost of a building that cannot be legally used or sold later.
Frequently Asked Questions
Is a CMDA-approved building always safe to buy?
An approval shows that the building was sanctioned under certain conditions. It does not confirm that construction matches the plan, that the builder is reliable or that the title is clear. Check each of these separately.
Can I check approval status before I visit the site?
Ask the developer for the approval numbers and dates, then ask a qualified professional or the relevant office to confirm them. Do not rely only on the numbers printed in a brochure.
What if the builder has added a floor without approval?
An unapproved floor can create legal and practical problems, including delays in completion certificates and possible orders to remove the extra construction. Ask for written confirmation of any regularisation before you agree to buy.
Is a completion certificate needed for a resale flat?
Yes, it is important to confirm that the building has a completion certificate. Ask the seller for a copy and check that it relates to the same building, block and survey number as the flat.
Who should I ask about approvals outside the metro limits?
Ask the seller or developer which planning authority sanctioned the layout and building, and then confirm the approval with that authority or with a qualified professional who works in that area.
Closing thoughts on approvals
CMDA approval is one of the most important foundations of a Chennai home, but it is only as good as the paperwork and the construction behind it. Read the approved plan, ask for each permission and certificate by number and compare the building with the drawings. A buyer who takes these steps early avoids the most expensive surprises that appear after the keys are handed over.
