What Is Building Approval?
Building approval (often called plan approval or planning permission) is the official sanction of your building plan by the authority responsible for your area. The sanctioned plan is the legal basis for your construction — banks ask for it before approving loans, and water, sewer and electricity connections, completion certificates and property registration all build on it.
When Do You Need Approval?
- New construction — houses, apartments, commercial and industrial buildings.
- Additional floors or extensions — adding to an existing approved building.
- Major alterations or reconstruction — structural changes to what was sanctioned.
- Change of use — for example, converting a residential building for commercial use.
- Dividing land — layouts and sub-division of plots need their own approval.
If your building already deviates from its sanctioned plan, the position depends on the nature of the deviation and the rules in force — we review these situations case by case.
Which Authority Applies to Your Property?
This is the question most owners get stuck on. In and around Chennai, three authorities matter most:
- CMDA — the Chennai Metropolitan Development Authority is the planning authority for the Chennai Metropolitan Area. Planning permission for layouts and for larger or special categories of buildings runs through CMDA.
- Greater Chennai Corporation (GCC) — the city corporation issues building permits within Chennai city limits, and handles sub-division, completion certificates and property tax assessment.
- DTCP — the Directorate of Town and Country Planning covers areas of Tamil Nadu outside the Chennai Metropolitan Area. We handle DTCP plan approvals and completion certificates too.
Many projects touch more than one authority — plus CMWSSB for water and sewer, TNEB for power, and TNRERA registration for eligible real-estate projects. Which combination applies depends on your property's location, size and use.
The Self-Certification Route
Eligible small residential buildings can use a simplified self-certification route — broadly, plots up to 2,500 sq.ft., built-up area up to 3,500 sq.ft., up to 2 dwelling units, G+1 or S+2 floors and a maximum height of 10 m, subject to the applicable rules. If your home qualifies, this can meaningfully simplify the approval. We check eligibility as part of the feasibility study.
How the Process Works
Every project follows the same broad path: feasibility check → documentation → application → authority review → follow-up → approval. We've written up the building approval process step by step, including what happens when the authority raises queries.
What Papers You'll Need
Authorities ask for ownership records, land records, plans prepared by licensed professionals, and — for some categories — NOCs from other departments. See the full building approval documents checklist.
Why Applications Get Delayed
- Incomplete or mismatched ownership papers (sale deed, patta, encumbrance certificate).
- Plans that don't match the rules — setbacks, floor space, height or land-use zoning.
- Authority queries that sit unanswered for weeks.
- Missing NOCs discovered late in the process.
Most delays trace back to files that were incomplete on day one. That's why we front-load the work: check feasibility first, complete the documentation, then submit.
What Trusted Walls Handles
We are a Chennai-based consultancy, established in 2021 and backed by 16 years of professional expertise in statutory approvals and planning permissions. For a typical project we handle the feasibility study, the document checklist, coordination of drawings, submission to the right authority, responses to every query, and follow-up until the approved papers are in your hand — with clear updates at every step.
Common Questions
Do I need approval even for a small individual house?
Generally yes — construction should happen against a sanctioned plan regardless of size. Eligible small homes may qualify for the simplified self-certification route described above. More answers in our building approval FAQs.
Can you check a plot before I buy it?
Yes. A site feasibility study looks at what can be built on the land and what approvals it would need — before you commit money to it.
My building already has approval issues. Can you help?
We review existing buildings case by case. Whether an issue can be resolved depends on the nature of the deviation and the rules in force — we'll tell you the honest position after studying the papers.