| Primary value | 1.5× road width ((typical absolute max + setback)) |
| Applies to | All buildings on plots facing a public road |
| Exceptions | Road < 9 m → Often 15 m height max |
| Road 9-12 m → Up to 24 m typical | |
| Road 12-18 m → Up to 30-45 m | |
| Road > 18 m → 70+ m permitted (with setbacks) | |
| High-Rise Buildings (>15m) → Buildings exceeding 15m in height are classified as 'High-Rise' and must comply with the stringent fire safety norms of NBC Part 4, regardless of road width. | |
| Special Planning Zones → Areas near airports (as per AAI norms), heritage precincts, defence zones, or ecologically sensitive areas have separate, often much stricter, height restrictions. | |
| Basements → The number of basements permitted is also often linked to road width to manage soil excavation and traffic during construction. | |
| Measured as | Building height = ground level to topmost habitable floor finished level. Roof tank rooms, mumty exempted up to specified limits. |
| Source | NBC 2016 — NBC 2016, Part 3, Clause 7.6.1 & Table 5; and relevant State/Local DCR ✓ Verified |
Building height is linked to road width primarily for public safety and urban amenity. Wider roads allow for easier access and maneuverability for fire tenders, especially for high-rise buildings. This rule also ensures adequate light and ventilation for buildings and the street, preventing the formation of dark, congested urban canyons.
Local Development Control Regulations (DCRs) provide specific tables linking road width to maximum permissible height. While a simple ratio like 1.5x road width is a common initial estimate, the actual height is governed by these tables, FAR limits, and setback requirements. In many metros, purchasing premium FSI/FAR allows for greater height, subject to fire safety and infrastructure norms.