Paint coverage by surface type

Coverage falls as a surface gets rougher or more absorbent. A gallon that covers 400 square feet of smooth primed drywall may only reach 150 square feet on bare brick, because texture adds hidden surface area and porous materials absorb the first coat instead of holding it on top.

Use the chart below to pick a coverage rate, then divide your area by it.

Coverage chart by surface

Typical planning ranges for one coat from one US gallon. Always check your own can, since these vary by brand and product line.

SurfaceSq ft per gallon, one coatNotes
Smooth primed drywall350 to 400The best case, and the figure printed on most cans
Light texture, orange peel300 to 350The most common finish in newer homes
Heavy texture, knockdown250 to 300Roller needs a thicker nap, which lays down more paint
Bare or new drywall, unprimed200 to 250Prime it instead. Primer is cheaper than topcoat
Smooth wood and trim350 to 400Brushing trim is economical, though slow
Bare or rough sawn wood150 to 250End grain and saw marks absorb heavily
Smooth exterior siding300 to 350Weathered siding sits at the low end
Stucco or masonry150 to 250Depends entirely on how deep the texture runs
Bare brick or block100 to 200Mortar joints and pores swallow the first coat

How to use the chart

Take your net area, multiply by coats, add waste, and divide by the rate from the table rather than the number on the can.

gallons = (net area × coats × (1 + waste)) ÷ surface coverage rate

Example: 600 square feet of knockdown texture, two coats, 10 percent waste. That is 600 × 2 × 1.1 = 1,320 square feet of coverage needed. At 275 square feet per gallon for heavy texture, that is 4.8 gallons, so buy 5. Using the can's 400 figure instead would have told you 3.3 gallons, and you would have run out most of the way through the second coat.

The paint calculator does this arithmetic for you, including the door and window subtraction.

Prime instead of adding coats

On any bare, porous, or patched surface, a coat of primer is almost always cheaper than the extra topcoat you would otherwise need. Primer is formulated to seal the surface so your finish paint sits on top of it and reaches its rated coverage, and it usually costs less per gallon than a quality finish paint. Two coats of expensive topcoat on bare drywall is the most common way to overspend on a paint job.

Frequently asked questions

How much less paint does textured wall coverage give you?

Expect 15 to 30 percent less than a smooth wall. Light orange peel costs you about 15 percent, while heavy knockdown or popcorn can cost 30 percent or more, because the texture adds real surface area that a flat measurement does not capture.

How many square feet does a gallon of paint cover on bare drywall?

About 200 to 250 square feet, well below the 350 to 400 on the can, because unprimed drywall paper and joint compound absorb the first coat unevenly. Priming first is both cheaper and gives a more even finish.

How much paint does brick need per gallon?

Roughly 100 to 200 square feet per coat, the lowest of any common surface. Mortar joints and the pores in the brick face absorb a great deal, so a masonry primer or filler coat is usually worth it before the finish coats.

Does paint sheen change coverage?

Only slightly. Higher sheen paints such as semi-gloss and gloss tend to be marginally thinner and can spread a little further, but the difference is small next to the effect of surface texture and porosity. Choose sheen for durability and washability, not for coverage.

Should I use a different coverage rate for ceilings?

Use the same rate as the wall surface if the ceiling is smooth and primed. Popcorn or heavily textured ceilings behave like heavy texture, so plan on 250 to 300 square feet per gallon and expect the first coat to be thirstier than the second.