Site Coverage Calculator
Enter the site area and building footprint to calculate the site coverage (footprint ÷ site area × 100%) and check it against an optional maximum allowed coverage. A Hong Kong planning density control indicator.
Input Data
Results
At a glance:Site coverage = building footprint projection area ÷ site area × 100%, showing the share of the site covered by the building. It is a density control used together with plot ratio. Allowed footprint cap = site area × allowed coverage%; if the actual footprint is below the cap it is compliant. Hong Kong low-density residential and village-type developments often set stricter coverage to preserve ventilation, daylight and open space.
Formula
Coverage = footprint / site × 100%
Allowed footprint = site × max coverage%
Compliant if footprint ≤ allowed footprint
$$SC = \frac{A_b}{A_s}\times 100\%$$$$A_{b,\max} = A_s \times \frac{SC_{\max}}{100}$$$$A_b \le A_{b,\max}$$How to Use
- Enter the site area (m²).
- Enter the building footprint (m²).
- Optionally enter the maximum allowed coverage (%).
- The tool outputs the coverage, allowed footprint and check.
Case Studies
Low-density residence
500 m² site, 300 m² footprint.
Coverage 60%; with limit 50% it exceeds and the footprint must shrink.
Village house lot
300 m² site, 90 m² footprint (3 storeys × 30 m² projection).
Coverage 30%; within most village-type development limits.
FAQ
How is coverage different from plot ratio?
Coverage looks at how much ground is taken up, while plot ratio looks at total floor area — they control different aspects of density.
Why limit coverage?
Limiting the footprint preserves ventilation corridors, daylight and open/green space, improving the microclimate and living environment.
Related Tools
References
Content review: Calculatorism Construction Team. Results are for reference only; please refer to the relevant authorities for the official figures.