Work out building height limit from road width instantly with clear inputs, formula shown and shareable results.
Height is commonly limited to a multiple of the abutting road width plus the front setback, which protects daylight to the street and keeps the canyon proportions reasonable. An absolute cap applies as well, usually driven by fire service reach or airport approach surfaces, and the lower of the two governs.
Height from road width
Height = ratio x (road width + front setback)
Governing limit
Permitted height = min(ratio-based height, absolute cap)
Preliminary estimate only. Height limits, ratios and absolute caps are set by local development control regulations and aviation or fire authority constraints.
Height = ratio x (road width + front setback). Height is commonly limited to a multiple of the abutting road width plus the front setback, which protects daylight to the street and keeps the canyon proportions reasonable.
Because daylight reaches the building across the whole open space in front of it, not just the carriageway. A generous setback earns proportionally more height.
This calculator takes 4 inputs: Abutting road width, Front setback, Height to width ratio permitted, Absolute height limit. The pre-filled defaults are a realistic worked example — replace them with your own site or project figures.