Delhi Air Funnel Zones: Building Height Restrictions

Two distinct restrictions operate around IGI, and confusing them costs buyers money. The red zone under the CCZM is the tighter ring: until 2020, the red zone covered 129 sq km around IGI, within which no structure above 18 m could be built without a mandatory AAI NOC. Following rule changes, the red zone area was reduced to 60 sq km, but the 18 m ceiling inside it remains unchanged. The approach funnel is more severe still, applying directly along the runway approach and departure paths. In the funnel, permitted height equals 2% of the distance from the runway edge: a plot 1,000 m from the runway edge is capped at just 20 m.

The CCZM divides the full 20 km radius into colour-coded grids, each carrying a Permissible Top Elevation (PTE) measured in metres above mean sea level (AMSL). The table below shows the key surface zones and what they mean for construction.

Delhi's CCZM threshold starts at just 7.77 m, meaning builders in this city need AAI approval for structures as low as a two-storey house in affected grids, far stricter than most other Indian cities. If a broker is showing you a plot in Dwarka, Mahipalpur, Kapashera, or Vasant Kunj without mentioning the CCZM grid reference for that survey number, treat that as a warning sign.

The IGI airport funnel is not an abstraction; it has put construction on hold at specific addresses. AAI directed the DDA to halt construction at nearly 100 plots in Dwarka Sector 8 after determining the buildings fell inside the runway 27/9 and 28/10 approach paths. That is the clearest on-record example of the funnel ending a buyer's plans after purchase.

The table below maps the major Delhi corridors by their relationship to the funnel zones and what that means practically.

The most misunderstood corridor is Vasant Kunj. News of eased norms in 2020 led many buyers and brokers to assume height restrictions no longer apply. They do. Eased norms mean the red zone shrank and the online NOCAS system simplified approvals; they do not mean any plot in Vasant Kunj is free of height limits. Every plot still sits within a CCZM grid with its own PTE figure, and the lowest applicable surface restriction governs.