Urban Design and Site Planning
Site planning questions link the plot to the city: development controls from the طرح تفصیلی, street hierarchy, parking provision, orientation, and privacy between neighbours. Expect small calculations rather than essays.
Core rules
- Control tools: ضریب سطح اشغال (coverage), تراکم (floor area ratio or storeys), عقبنشینی (setbacks), بر (projection), حریم and height limits. Coverage × plot gives the footprint; footprint × permitted floors gives gross built area.
- Street hierarchy runs from the 6 m access lane to 8, 10 and 12 m collectors; the narrower the lane, the more the design must handle turning, fire access and parking.
- Parking is mandatory per use, with stall dimensions around 2.5 × 5.0 m plus an aisle; ramps to basements have slope limits and need transition zones.
- Orientation: living spaces face south for winter sun, studios and kitchens take north light, bedrooms avoid the west afternoon sun in hot regions.
- Privacy (اشراف): windows and terraces should not look into a neighbour's rooms, even when setbacks are legally met.
Worked example
Plot 250 m², coverage 60%, four storeys, one parking space per unit. Footprint = 0.6 × 250 = 150 m²; gross built = 4 × 150 = 600 m². Allow about 15% for stairs, lobby and shafts, leaving roughly 510 m² net, i.e. four flats of about 125 m². Four flats means four stalls plus aisle, which will not fit at grade on 100 m² of open land, so a basement ramp is required. The reasoning step - checking parking against residual site area - is what earns the mark.
Traps
- Treating gross built area as sellable area.
- Forgetting that basement area may or may not count toward تراکم depending on the zone.
- Assuming setbacks are equal on all four sides.
- Ignoring site slope for drainage and ramp length.