Short answer: Often, yes. Around civil airports, a building taller than the permitted top elevation for its grid needs a height clearance from the Airports Authority of India through its NOCAS portal. Below that height, AAI says no NOC is needed. Before booking a high floor in North Bengaluru, ask for the NOC and match its approved height to the sanctioned plan.
- Height near airports is capped by a grid map. AAI calls it the Colour Coded Zoning Map, or CCZM.
- Above the grid height, a NOC is required. It states the maximum top elevation allowed for that site.
- The NOC has a validity and can be revalidated. Check the date.
- Floors above the NOC height are a red flag. They may never get an occupancy certificate.
- Why do airports limit building height?
- What is the Colour Coded Zoning Map?
- How do you check a project's height clearance?
- What if the building is taller than the NOC?
- Does airport proximity affect daily life too?
- What about plots and individual houses?
- Does the north Bengaluru corridor have other checks?
- Buyer checklist: tall flat near an airfield
- Related reading
- Frequently asked questions
- Talk it through with acre&key
- Sources
North Bengaluru has seen a wave of tall towers along the airport road corridor, from Hebbal to Devanahalli. Many buyers pick upper floors for views and breeze. Few ask the one question that decides whether those floors are legal: how high is the building allowed to go?
Why do airports limit building height?
Aircraft approach and leave on fixed paths. Tall structures near those paths can be a safety hazard. India regulates this through height rules issued by the Ministry of Civil Aviation, and AAI runs the clearance process. AAI's online system for height clearance is called NOCAS: No Objection Certificate Application System.
On its NOCAS home page, AAI says:
- A NOC from AAI is not required for a structure below the CCZM height.
- NOC for height clearance is not required for any structure more than 56 km from the navigation facility serving the aerodrome.
- Applicants file revalidation applications through NOCAS.
That 56 km radius covers a large part of North and Central Bengaluru from Kempegowda International Airport. Bengaluru also has other airfields, including HAL and the Yelahanka air base. Clearances near defence airfields can involve other authorities. Ask the developer which authority issued theirs.
What is the Colour Coded Zoning Map?
The CCZM divides the area around an airport into grids. Each grid carries a Permissible Top Elevation, measured above mean sea level. If your building's top, including water tanks, lift rooms and antennas, stays below that elevation, no NOC is needed. If it goes above, the developer needs a NOC.
NOCAS also offers an approximate permissible top elevation check using site coordinates. AAI notes the result is indicative only and the actual permissible height may vary. Treat it as a first screen, not a clearance.
A quick note on maths: elevation is above sea level, not above the ground. A building's allowed height is roughly the permitted top elevation minus the ground elevation at the site. Bengaluru sits around 900 m above sea level, and the ground varies across the city, so two sites with the same grid value can have different allowed heights.
How do you check a project's height clearance?
- Ask the developer for the AAI NOC. It carries a NOC ID, the site coordinates, the permitted top elevation and the validity date.
- Verify the NOC ID on NOCAS. The home page has a NOC ID lookup.
- Match coordinates. The coordinates on the NOC should match the project site.
- Compare heights. The sanctioned building height plus the ground elevation should stay within the NOC's top elevation.
- Check validity. If the NOC expired, ask for the revalidation.
- Look at the RERA page. Approvals uploaded there should include the NOC for tall projects. See how to check a project on RERA Karnataka.
If the developer says a NOC is "not required", ask for the CCZM check that proves the building stays below the grid height.
What if the building is taller than the NOC?
Then some floors may not be approvable. Planning authorities typically need the NOC before sanction, and the occupancy certificate checks the building against the sanctioned plan. A floor above the permitted height can block the OC for the whole building or for those floors. See our guide on OC and CC.
Signs of trouble:
- The brochure shows more floors than the plan sanction.
- The developer says extra floors are "in approval".
- The NOC is for a lower height than the tower being sold.
- The NOC belongs to a different survey number.
If you see any of these, don't buy those floors until the paperwork catches up.
Does airport proximity affect daily life too?
Height is the legal question. Noise is the lived one. Flats under a flight path can hear aircraft often, at night too. Visit at different times and stand on the balcony. Our North Bengaluru property guide and the Devanahalli zoning explainer cover the wider area.
Being near the airport has upsides: travel time, jobs in the aerospace and logistics belt, and planned infrastructure. Balance those against noise and the height cap on future towers around you. A height cap can also protect your view, because neighbours can't rise much higher either.
A height NOC does not evaluate or address decibel noise levels. If the building sits close to the flight path, visit at early morning and late evening takeoff/landing windows to test noise levels on higher balconies. High-performance double-glazed acoustic windows can significantly dampen noise, but verify whether the developer includes them in the base specifications.
What about plots and individual houses?
Most low-rise houses sit well below the grid height and need no NOC. But a plot buyer planning four or more floors near the airport should check the CCZM before buying. A plot priced for a tall building loses value if the grid allows less.
Does the north Bengaluru corridor have other checks?
Projects near the airport, in areas like Devanahalli, Yelahanka and along the Ballari Road corridor, often sit on converted agricultural land. So along with the height NOC, check the land conversion order, the planning authority approval and the khata. Our Devanahalli vs Yelahanka and Hebbal vs Thanisandra guides cover what differs in each area.
Buyer checklist: tall flat near an airfield
- [ ] Developer has shared the AAI NOC or a CCZM below-height check
- [ ] NOC ID verified on NOCAS
- [ ] Coordinates match the site
- [ ] Permitted top elevation covers the full sanctioned height
- [ ] NOC valid or revalidated
- [ ] Plan sanction floor count matches the brochure
- [ ] NOC uploaded on the RERA page
- [ ] Flight path noise checked at different hours
- [ ] Defence airfield clearance checked if near HAL or Yelahanka
Related reading
Frequently asked questions
NOCAS is the Airports Authority of India's online system for height clearance of buildings and structures around civil airports. Developers apply there, and the site lets anyone look up a NOC by its ID.
No. AAI says a NOC is not required for a structure below the height in the Colour Coded Zoning Map, or beyond 56 km from the navigation facility serving the airport.
NOCAS offers an approximate permissible top elevation check if you enter site coordinates. AAI says the result is indicative and the actual permitted height may vary, so rely on the NOC itself.
Those floors may not match the sanctioned plan or the height clearance, which can hold up the occupancy certificate. Avoid paying for any floor that the NOC and sanction don't cover.
NOCs carry a validity period, and AAI accepts revalidation applications through NOCAS. Check the date on the NOC and ask for the revalidation if it has lapsed.
Lawyer note: Height clearance and approvals on this page are general information, not legal advice. An architect or property lawyer should match the NOC, the plan sanction and the building height before you pay.
Sources
Checked 29 Oct 2026.
- Airports Authority of India, NOCAS home page (CCZM, 56 km note, revalidation, approximate elevation tool): https://nocas2.aai.aero/nocas/
- Airports Authority of India: https://www.aai.aero/
- Karnataka RERA, project search: https://rera.karnataka.gov.in/viewAllProjects?language=en
- GBA building plan approval system, public FAQ: https://bpas.bbmpgov.in/BPAMSClient4/CommonForms/FAQs.aspx
