What the spreadsheet contains
The worked example is below, with the formula columns already calculated. Replace the dimensions with your own and the derived columns follow.
| Room | Length (ft) | Width (ft) | Height (ft) | Floor area (sq ft) | Gross wall area (sq ft) | Openings (sq ft) | Net wall area (sq ft) | Finishing @ Rs 1,850/sq ft | Beams, ducts, notes |
|---|---|---|---|---|---|---|---|---|---|
| Living / dining | 17.5 | 11.0 | 9.5 | 192.5 | 541.5 | 58 | 483.5 | 356125 | Beam 9 in at the dining end, 8 ft 2 in clear |
| Kitchen | 9.0 | 7.5 | 9.5 | 67.5 | 313.5 | 24 | 289.5 | 124875 | Duct on the north wall, 14 in projection |
| Utility / dry balcony | 7.0 | 3.5 | 9.5 | 24.5 | 199.5 | 12 | 187.5 | 45325 | Washing machine point at 40 in AFL |
| Master bedroom | 12.0 | 11.0 | 9.5 | 132.0 | 437.0 | 42 | 395.0 | 244200 | Wardrobe wall is plumb; check the window sill height |
| Master bathroom | 7.5 | 4.5 | 8.5 | 33.8 | 204.0 | 16 | 188.0 | 62438 | Sunk slab, existing trap at the far corner |
| Bedroom 2 | 11.0 | 10.0 | 9.5 | 110.0 | 399.0 | 38 | 361.0 | 203500 | Column projects 6 in at the door corner |
| Common bathroom | 6.5 | 4.0 | 8.5 | 26.0 | 178.5 | 14 | 164.5 | 48100 | Non-sunk, stack on the shared wall |
| Passage | 12.0 | 3.5 | 9.5 | 42.0 | 294.5 | 20 | 274.5 | 77700 | Two door openings, electrical DB on the left wall |
| Balcony | 9.0 | 4.0 | 9.5 | 36.0 | 247.0 | 0 | 247.0 | 66600 | Open on one side, chhajja above |
| Foyer | 5.0 | 4.0 | 9.5 | 20.0 | 171.0 | 21 | 150.0 | 37000 | Main door opens inward, clockwise |
Columns E, F, H and I are live formulas in the spreadsheet. Costs are ex-GST at an indicative Rs 1,850 per sq ft.
How to measure
- Measure each room three times — at floor, at mid height and just below the lintel — and enter the smallest. Mumbai walls are rarely parallel.
- Record beam depth and column projection in the notes column with their height from floor. These change the layout more than the room size does.
- Add up your openings before entering them. Window plus door area per room, deducted from gross wall area, gives what you actually paint.
- Change the 1,850 in column I to your own per sq ft rate and the indicative cost updates across every room.
What it prevents
- Ordering paint against gross wall area. The openings deduction on a 2BHK is usually 200 to 250 sq ft, which is four to five litres.
- A layout drawn against a builder's plan. As-built dimensions differ from drawings by 2 to 6 inches often enough to matter.
- Discovering a duct after the kitchen is designed. The notes column is the cheapest place to catch it.
Convert areas with the carpet to built-up converter, or price the work on the interior design cost page.
Frequently asked questions
Why measure three times per room?+
Because walls lean. A 12 ft room can measure 12 ft 2 in at floor level and 11 ft 10 in at lintel level in an older Mumbai building. Joinery is built to the smallest dimension, so that is the one that goes on the sheet. Measuring once, at waist height, is how wardrobes end up 40 mm too wide.
Should I measure carpet area or built-up?+
Carpet, always, for interiors. Carpet area is what you can put furniture on and what interior work is priced against. Built-up includes wall thickness and built-up-with-loading includes common areas, neither of which you are furnishing.
What is gross versus net wall area?+
Gross is the full perimeter multiplied by height. Net deducts the window and door openings. Paint, wallpaper and wall panelling are quantified on net area; a contractor quoting on gross area is quoting for about 10 per cent more material than the job needs.
Do I need a laser measure?+
It helps and they cost under Rs 3,000, but a steel tape and a second person is fine. What matters more is being systematic: same three heights in every room, openings recorded separately, and beams and ducts noted with their projection and height.
Can I use this sheet for a commercial space?+
Yes, though for an office you would normally also record slab-to-slab height, the sprinkler grid and the column grid, none of which this sheet has columns for. Add them as extra columns; the formulas will not mind.