How much paint do you need for a room or building?
Buying short leaves a visible join. Buying long wastes money. The arithmetic, and the step people skip.
By The Sandtex Team · · 1 min read
The sum is simple. The mistake is almost always in what gets left out of it.
Measure the walls, subtract the openings
Multiply each wall's height by its width, add them together, then subtract doors and windows. That is your paintable area.
Divide by the coverage rate
Every Sandtex product lists a coverage rate in square metres per litre. Divide your area by that figure — then multiply by the number of coats.
That multiplication is the step most often skipped, and it is why people run out halfway up the second coat.
Add ten per cent
Textured or previously unpainted surfaces drink more than smooth ones. The margin also means later touch-ups come from the same batch, which matters more than people expect — colour varies slightly between batches.
Two tins from different batches on the same wall will not match under daylight, however identical the label.