Height, Coverage and Parking on a 1,200 m² Plot
A developer holds a 1,200 m² plot with a 30 m frontage on a 12 m road and a 40 m depth, in a zone where the development control rules read: maximum ground coverage 40 per cent, maximum FAR 1.8, front setback 6 m, rear setback 4 m, side setbacks 3 m each, maximum height 15 m. Floor-to-floor height is to be 3.2 m. Parking must be provided at 1 equivalent car space (ECS) per 100 m² of built-up area, and each surface ECS, including aisles, consumes 25 m²; parking inside mandatory setbacks is not permitted. The promoter's architect proposes five floors and argues that dropping ground coverage to 35 per cent keeps the FAR at 1.75, below 1.8, so five floors must be lawful.
1. Determine the maximum permissible built-up area under these rules and identify which control actually governs it.
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Footprint from setbacks. Width = 30 − 3 − 3 = 24 m; depth = 40 − 6 − 4 = 30 m → 720 m².
Coverage cap. 40 per cent of 1,200 = 480 m². This is smaller than 720 m², so coverage governs the plate: the maximum footprint is 480 m², not 720 m².
FAR cap. 1.8 × 1,200 = 2,160 m².
Height cap. 15 ÷ 3.2 = 4.69 → 4 floors (4 × 3.2 = 12.8 m; a fifth floor reaches 16.0 m and breaches the cap).
Permissible built-up area = 480 × 4 = 1,920 m², an achieved FAR of 1,920/1,200 = 1.60.
Which rule binds? Coverage fixes the floor plate and height fixes the number of storeys. The FAR ceiling of 2,160 m² is never reached - 240 m² of entitlement is stranded. Any scheme that tries to spend that entitlement must buy it with height, and height is the wall.
2. Compute the parking requirement for the permissible scheme and test whether surface parking can meet it on this plot.
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Requirement = 1,920/100 = 19.2 → 20 ECS (round up; a rule that permits 19 simply leaves the twentieth car on the street). Area required at 25 m² per surface ECS = 20 × 25 = 500 m².
Space actually available:
- Plot 1,200 m², footprint 480 m² → open area 720 m².
- Of that, the mandatory setback band is 1,200 − 720 = 480 m² (the 720 m² here being the setback-limited footprint of 24 × 30 m), and parking is not permitted there.
- Free open area = 720 − 480 = 240 m² → 240/25 = 9.6 → 9 ECS at the very best, and that assumes every remaining square metre is usable, which it is not once a boundary wall, gate, ramp and pedestrian path are placed.
Shortfall = 20 − 9 = 11 ECS, about 275 m².
Judgement: surface parking cannot satisfy the standard on this plot. The real options are a basement for 11–13 ECS, a stilt/covered ground floor if the rules exempt stilt parking from coverage, or a reduction in built-up area. Parking is a second binding constraint alongside height, and it is the one most often discovered after the sanction drawings are complete.
3. Assess the architect's five-floor proposal. If it is not lawful, what would be lawful, and what does the proposal cost?
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Test each control, not just FAR.
- Footprint = 35 per cent × 1,200 = 420 m²; built-up area = 420 × 5 = 2,100 m²; FAR = 2,100/1,200 = 1.75 ≤ 1.8 ✓
- Height = 5 × 3.2 = 16.0 m > 15 m ✗
The argument fails. FAR compliance is necessary but not sufficient; the height cap is an independent control and it governs here, exactly as it governed the lawful four-floor scheme.
Lawful alternatives:
- Five floors at 3.0 m floor-to-floor = 15.0 m, if the rules allow the 15 m cap to be met exactly and lifts, water tank, parapet and staircase headroom fit within it - in practice this needs a written clarification, not an assumption.
- Four floors as of right at 480 m² coverage = 1,920 m².
Cost of the proposal: the extra floor yields 2,100 − 1,920 = 180 m² of floor area, and it makes the parking position worse. At 2,100 m² the requirement rises to 21 ECS, while the smaller footprint frees 780 − 480 = 300 m² of open area, i.e. 12 surface ECS - now 9 short instead of 11.
Judgement: refuse the five-floor submission. The promoter is trading 60 m² of ground-level open space for 180 m² of floor, and paying for it with a clear height violation and a deeper parking deficit that will surface as an occupation-certificate problem.