The 30 × 40 is one of India's most common plot sizes. On it, every metre of setback and every centimetre of wall thickness shows up in the rooms you get.
Built-Up Area
Worked example with typical setbacks for a plot of 100–200 m² on a road up to 12 m (about 1.5 m front, 1 m sides and rear):
- Width: 30 ft (9.14 m) − 2 × 1 m = 7.14 m
- Depth: 40 ft (12.19 m) − 1.5 − 1 = 9.69 m
- Footprint: about 69 m² = about 745 sq ft with the plot's 30 ft side on the road
Orientation and road width change this; many 30 × 40 plots land at about 750–850 sq ft per floor. Your architect fixes it from the rules.
What Fits
| Layout | Fits? |
|---|---|
| Compact 2BHK, two toilets | Yes, on one floor |
| 3BHK | As a duplex |
| Two 1BHK rental units | Yes, per floor |
| Car parking | Usually in the front setback or as a stilt floor |
Layout Tips for a Narrow Plot
- Use 4–6 inch AAC for internal walls to recover floor area.
- Stack the staircase on the side setback (external) or tuck it along a side wall (internal).
- Combine living and dining in one space.
- Kitchen and toilets back to back to share plumbing.
- Windows on the long sides for cross-ventilation.
Cost
| Configuration | Built-up | Standard (₹2,000–2,500) |
|---|---|---|
| Ground only | ~800 sq ft | ₹16 – 20 lakh |
| G+1 | ~1,650 sq ft (incl. stair) | ₹33 – 41 lakh |
| G+2 | ~2,450 sq ft | ₹49 – 61 lakh |
Add 10–20 percent for approvals, design fees, sump, septic tank, compound wall and connections.
The Short Version
About 800 sq ft per floor: a 2BHK on one level or a duplex 3BHK. Use thin internal walls, an efficient stair and back-to-back wet areas, and budget ₹33–41 lakh for a standard G+1.
