How much paint do I need?
The wall, times the coats, plus a tenth spare.
- For
- Buy the right number of cans once, with a little spare for touch-ups.
- When
- Before you quote, and before you shop
Try it
60 of wall, 2 coats, a can that covers 35: buy 4 cans.
Cans = wall × coats × 1.1 ÷ what one can covers, rounded up.
Measure every wall, count every coat, add a tenth.
Worked out
| Wall | 1 coat | 2 coats | 3 coats |
|---|---|---|---|
| 20 | 1 | 2 | 2 |
| 40 | 2 | 3 | 4 |
| 60 | 2 | 4 | 6 |
| 100 | 4 | 7 | 10 |
Easy to get wrong
- Forgetting the second coat.
- Trusting the can’s best-case cover.
- Buying exact, then running out mid-wall.
- Paint from two batches on one wall.
The tool for it
Questions
Do I take off doors and windows?
Take off the big ones. Leave the small ones in; they become your spare.
Where do I find what a can covers?
On the can or the maker’s sheet. Use the low end on rough walls.
Does a new wall need more?
Yes. Bare or patched walls soak it up, so prime them first.
Metres or feet?
Either. Use one unit for the wall and the can, and the sum works.
Why a tenth spare?
For waste, the roller tray and touch-ups after the job.
Does a dark colour need more coats?
Often a third coat, or a tinted primer under it.
Do I charge for the spare?
Yes, it’s part of the job. Leave what’s left with them, labelled.
How do I measure a wall fast?
Length round the room times its height. A ceiling is length times width.