How Much Behr Paint Do I Need?

How much Behr paint do I need? Worked examples

12×12 room, 8 ft ceilings, walls only ≈ 384 sq ft. Two coats at Behr’s 400 sq ft/gallon label rate = 768 ÷ 400 ≈ 1.9 gallons — buy 2 gallons if walls are smooth and primed. Texture or a big colour change? Use 350 sq ft/gallon and buy 3.

10×12 bedroom with two doors and one window: deduct openings in the calculator, keep two coats, and expect roughly 2 gallons of Behr Premium Plus Interior for walls. Always confirm with the exact “Coverage” line on your can.

For coverage-only math (sq ft ÷ label rate), use the Behr paint coverage calculator. Stay here when you want coats, waste, and store quantities in one pass.

Why gallon estimates matter before you buy

Running short mid-project means a second trip to the store — and the new can may not match the first batch exactly. Buying too much leaves sealed gallons in the garage for years.

Enter your exact dimensions above for your project. The quick answer box uses a typical Canadian DIY room so you have a starting point before you measure.

Primer vs topcoat — run the numbers twice

New drywall, water stains, or a jump from navy to white usually needs primer first. Primer often covers less area per gallon than finish paint — check the label and run the calculator once per product.

If you are only refreshing the same colour on sound walls, one coat may be enough. Our how many coats guide walks through when two coats are non-negotiable.

Canadian paint labels and coverage

Coverage on Canadian cans is listed in square feet per litre or per gallon depending on the brand. Benjamin Moore, Sherwin-Williams, and Behr Canada all print coverage on the back — enter that number in project settings for the most accurate result.

Flat and ceiling paints often cover more than high-gloss trim. Textured walls and deep colours cover less — the 10% waste setting helps, but add extra for orange peel or knockdown texture.