Question 1

Should I buy primer separately?

Accepted Answer

New plaster, bare wood and stained or very dark surfaces usually need a primer or a thinned mist coat; it has its own coverage figure.

Question 2

How much paint do I need for a ceiling?

Accepted Answer

Set "Include ceiling" to 1. Ceiling paint is often applied in two coats too; some ceiling paints have different coverage.

Question 3

Why add 10%?

Accepted Answer

Paint is lost in rollers, trays and absorption, and walls are rarely perfectly smooth. 10% is a common allowance.

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