How it works

The estimate multiplies wall area by the number of coats, then divides by the paint coverage entered on the tin. Add extra for texture, absorption, and waste.

Standard formulalength × height × coats / coverage

Worked example

A 5 m × 2.5 m wall with two coats and 10 m²/L coverage needs 2.5 litres before extra allowance.

Frequently Asked Questions

Does this include doors and windows?

No. Subtract their area from the wall area before entering the length or use an allowance.

What is coverage?

It is the area one litre can cover according to the product label.

Should I add extra paint?

Usually yes for texture, porosity, colour changes, and waste.

Can I calculate several walls?

Add their areas together before entering the dimensions.