In this guide — 6 sections
The most common causes are setback non-compliance, FSI exceedance, road width discrepancy, survey number mismatch across documents, parking deficiency, absent rainwater harvesting, unsigned drawings, area statement errors, Patta not in the applicant’s name, zoning mismatch, and encroachment on the road margin. All eleven are preventable with pre-filing checks.
Building plan rejections feel arbitrary from the outside. They are not. Nine of the eleven reasons below are entirely preventable at pre-filing stage, and the remaining two require revenue department actions that can be completed before filing.
How Checkers actually work through a file
Plan checkers work through a defined order, and every rejection or deficiency notice traces back to one of these eight points. That is what makes the outcome predictable rather than arbitrary — and it is why a pre-filing check against the same eight headings catches most problems before an officer ever sees the file.
A deficiency notice is a formal query raised on TNOBPAS where an application has errors or omissions that are correctable but not grounds for immediate rejection. The notice specifies the deficiency, and the architect must respond with a corrected application within the response period. Deficiency notices are the most common outcome of first-round scrutiny — outright rejection without one is less common for straightforward applications.
Design and Measurement failures
The first two are bordered because they are the ones that force a redesign rather than a correction:
Setback non-compliance
Most commonConfirm setback norms from the TNCDBR 2019 table and applicable area regulations before floor plan design begins. For CMA plots, take road width from the approved layout plan or the CMDA road schedule — not from physical measurement. Verify the setback formula for your road width and height combination before the site plan is drawn.
FSI exceedance
Confirm the applicable FSI for your zone before design begins. Ask the architect to produce the area statement in parallel with the floor plan and verify it before finalising. The statement must match the drawn areas — a discrepancy between stated and drawn is itself a rejection trigger.
Road width discrepancy
Take the width from the approved layout plan where the plot is in a layout; obtain a road width certificate from the municipality for municipal roads. Do not self-measure. Where the layout plan differs from ground conditions, an architect familiar with the area can advise which figure the authority will use.
Land use or zoning mismatch
Check zoning in the CMDA Development Plan or DTCP local area plan for your plot’s survey number, before design. If the zoning does not permit the intended use, a zoning change or special permission process is required before a standard application can be filed at all.
Survey number inconsistency
Cross-check every document’s survey number before submission. Resolve discrepancies through the Tahsildar’s office before filing. An architect familiar with your local area can identify the correct number to use for the TNOBPAS submission.
Parking norm deficiency
Calculate parking requirements before the ground floor plan is designed. Bays must be dimensioned at a minimum of 2.5m × 5m per car and shown on both site plan and ground floor plan. If the plot cannot accommodate the requirement within the setback envelope, the design must change before filing.
Rainwater harvesting absent or inadequate
Include a properly designed plan in every submission above the threshold, showing roof catchment area, first-flush diverter, recharge pit count and dimensions, and sump volume computation. The architect should verify designed capacity meets the minimum before filing.
Five of these seven share one root cause: designing before confirming. Setbacks, FSI, parking and rainwater harvesting are all constraints that exist before a single line is drawn — and each fix above begins with the same instruction, which is to establish the number first. Road width is the outlier worth watching, because it is the one people are most tempted to measure themselves, and a self-measurement that includes the footpath or drain quietly corrupts both the FSI and the setback that follow from it.
Document and boundary failures
Unsigned or unstamped drawings
Purely clericalEvery sheet — site plan, floor plans, elevations, sections — must carry the architect’s signature, COA registration number and firm stamp before upload. Verify that the digital signature on the submission matches the architect’s Class 3 DSC.
Area statement computation error
Produce the area statement as a structured computation from the floor plans, not a separate estimate. Include all areas and explicitly note the exclusion basis for any excluded item. Have the arithmetic independently checked before filing.
Patta not in applicant’s name
Revenue actionInitiate mutation immediately after purchase completion; it typically takes 2–4 weeks. Do not commence design or pay architecture fees until mutation is confirmed. Download the updated Patta before filing.
Encroachment on road margin
Revenue actionVerify the legal boundary from the approved layout plan, Patta and revenue records — not from the physical fence or wall. Where there is any ambiguity about where the road margin ends and the plot begins, obtain a survey from a licensed surveyor before design.
Reason 8 deserves a moment, because it is the cheapest failure on the list and the most galling. A fully compliant design — correct FSI, correct setbacks, adequate parking, properly computed rainwater harvesting — is rejected at document verification because a signature is missing from one sheet. Nothing about the building is wrong. The check takes minutes and belongs in the upload routine rather than anyone’s memory.
Reasons 10 and 11 are the revenue department pair, and they behave differently from the other nine. Patta mutation runs to the Tahsildar’s clock at two to four weeks; a boundary survey needs a licensed surveyor. Neither can be resolved by revising a drawing, which is why both belong at the very start of the sequence — and why the guidance on mutation is unusually blunt: do not commence design or pay architecture fees until it is confirmed.
A Pre-Filing Check Against the Same Eight Headings
Plan checkers use a fixed sequence. Running the file against that same sequence before submission catches most problems before an officer ever opens it.
Resubmission after a deficiency notice
After a deficiency notice
Four steps, and one of them decides whether there is a second roundReceive the notice via TNOBPAS
Posted to the applicant’s account by the plan checker, with the architect notified at their registered email. Check the portal regularly — deficiency notices are not always communicated by phone.
Analyse it with the architect
Each notice specifies the exact scrutiny point that failed. The architect reviews it against the drawings to identify whether it is a drawing error, a missing document, a required design modification, or a document to be obtained from a third party such as the Tahsildar or municipality.
Prepare the corrected response
Upload corrected drawings or additional documents within the response period. The response must address every point in the notice — a partial response that resolves some but not all deficiencies generates a second round.
Expect a timeline reset
After the response is submitted, the scrutiny timeline partially resets. Plan for one additional 2–4 week round per response, and note that projects with multiple deficiency rounds can add 6–12 weeks overall.
Step three is where a single round becomes several. A response that resolves four of five deficiencies is not four-fifths finished — it generates a fresh notice for the fifth, and another two to four week cycle with it. Answering everything in the notice, including the points that seem trivial, is what keeps one round from becoming three.
Pre-Filing compliance checklist
One line per reason, in the order a checker would encounter them:
Swipe or scroll to see the full table →
| Check | Before TNOBPAS submission |
|---|---|
| FSI calculated from the area statement; total does not exceed permitted FSI × plot area | |
| Setback distances confirmed from TNCDBR 2019 and applicable area regulations for road width and building height | |
| Road width confirmed from the approved layout plan or municipality road schedule — not self-measured | |
| Land use and zoning confirmed from the CMDA Development Plan or DTCP local area plan | |
| All document survey numbers cross-checked: Patta, Sale Deed, approved layout plan, site plan | |
| Parking count and dimensions confirmed against the minimum; dimensioned bays shown on the site plan | |
| Rainwater harvesting plan included; sump volume and recharge pit count computed for the catchment area | |
| Every drawing sheet signed and stamped by the COA-registered architect, with the COA number on every sheet | |
| Area statement independently checked for includable area computation and arithmetic | |
| Patta in the applicant’s name confirmed — mutation complete if recently purchased | |
| Plot boundary verified from revenue records; no encroachment on the road margin shown |
For the full process, see the TNCDBR process guide, and to establish which authority applies to your plot, CMDA against DTCP against local body.
A Partial Response Is How One Round Becomes Three
Resolving four deficiencies out of five generates a fresh notice for the fifth — and another two to four weeks with it.
Most building plan rejections are actually unresolved deficiency notices, not outright rejections.
— Which is why the response matters more than the notice
Frequently Asked Questions
What are the most common rejection reasons?
Setback non-compliance, FSI exceedance in the area statement, road width discrepancy, survey number inconsistency across documents, parking norm deficiency, absent or inadequate rainwater harvesting, unsigned drawings, area statement computation errors, Patta not in the applicant’s name, land use zoning mismatch, and encroachment on the road margin.
What is a deficiency notice?
A formal query raised by the plan checker on TNOBPAS where an application has correctable errors. The notice specifies the exact scrutiny point that failed, and the architect responds with corrected drawings or documents within the prescribed period. Most building plan rejections are actually unresolved deficiency notices rather than outright rejections.
What should I do if my application is rejected?
Review the notice with your architect; identify whether corrections require drawing revisions, design modifications or third-party documents; upload the corrected response within the response period; and monitor the portal for the next scrutiny round. Respond to every point in the notice in each response, not just the substantive ones.
How long does resubmission take?
Each response round typically adds 2–4 weeks to the scrutiny timeline after the corrected response is submitted. Projects with two or more rounds can add 6–12 weeks overall — which is why a complete and accurate first application is significantly more time-efficient than correcting notices after the fact.
Can approval be rejected for unsigned drawings?
Yes. All drawing sheets must be signed and stamped by the COA-registered architect filing the application. Drawings uploaded without the signature, COA registration number and stamp on every sheet are rejected at document verification — and this is one of the most easily preventable reasons on the entire list.
How do I fix a setback violation?
The floor plan must be redesigned to reduce the building footprint so every setback meets the minimum. If the design cannot be modified — because the site is too small for the desired room count at the required setback — then the room count or building coverage must be reduced before resubmission. There is no way to argue around it.
Is rainwater harvesting mandatory for all buildings?
Mandatory under TNCDBR 2019 above specified built-up area thresholds, and most residential G+1 and above projects exceed them. A properly designed plan showing roof catchment area, recharge pits with dimensions and sump volume must be included — a plan shown but not designed is treated as a deficiency.
Why does road width matter so much?
Because it determines both the applicable FSI — higher FSI is permitted on wider roads in most CMA zones — and the minimum front setback, since wider roads require greater setbacks. The authority verifies the submitted width against official records, so an overstated width from self-measurement produces incorrect FSI and incorrect setback calculations at once.
Which reasons cannot be fixed by revising drawings?
Two: Patta not in the applicant’s name, which requires mutation at the Tahsildar’s office and typically takes two to four weeks; and encroachment on the road margin, which needs a licensed surveyor to establish the legal boundary. Both should be resolved before design begins rather than after filing.
How much of this is genuinely preventable?
Nine of the eleven reasons are entirely preventable at pre-filing stage, and the remaining two require revenue department actions that can also be completed before filing. Since plan checkers work through a fixed scrutiny sequence, running the application against that same sequence beforehand catches most issues before submission.
Every Application Checked Before It Reaches the Portal
COA-registered architects running the same eleven checks a plan checker will run — while corrections still cost an afternoon rather than a scrutiny round.
A sequence, not a lottery
Building plan rejection always traces back to one of these eleven reasons, because they are the product of a defined scrutiny sequence rather than an unpredictable one. A deficiency notice adds weeks to months to the timeline and, where design modification is required, real cost — and the checklist above eliminates most of the causes before submission. Contact Buildiyo for approval assistance.