Building coverage ratio (Dutch: bebouwingspercentage, abbreviated BP) is the maximum percentage of a plot of land that may be covered by buildings, as specified in the local zoning plan. It controls building density and ensures sufficient open space for light, air, gardens, and drainage.
How it is calculated
The building coverage ratio is calculated with a simple formula:
BP = (total footprint of all buildings on the plot / total plot area) x 100%
The footprint includes the ground-floor area of the main building plus all outbuildings, garages, sheds, and covered structures. Uncovered terraces, swimming pools, and paved areas generally do not count toward the built footprint, although local rules may vary.
For example, if a plot measures 500 m² and the zoning plan allows a building coverage ratio of 60%, the total footprint of all structures may not exceed 300 m².
Typical values
Building coverage ratios vary widely depending on the type of area:
- Urban residential zones — 50% to 70%, allowing a substantial portion of the plot to be built upon.
- Suburban residential zones — 30% to 50%, preserving more garden space.
- Rural and agricultural zones — often below 20%, maintaining the open character of the landscape.
- Commercial and industrial zones — can reach 80% or more, reflecting the need for large buildings.
Application in construction
The building coverage ratio is one of the first things to check when planning a building project. It directly determines how large a building can be in relation to the plot. Exceeding the allowed ratio means the building permit will be refused unless a variance is granted. Architects use the ratio alongside other zoning parameters — such as maximum building height, setback distances, and floor area ratio — to design a building that fits within all regulatory limits.
Related terms
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