Paint & interior finishes
How Much Exterior Paint Do I Need for a House?
By the HomeCalc USAReviewed against our editorial policyLast updated US units and pricing
Multiply the perimeter of the house by its wall height to get gross wall area, subtract windows and doors, then divide by the coverage on the can — typically 350 sq ft per gallon on smooth siding and 250 on rough. Double it for two coats. A typical 2,000 sq ft two-story home needs roughly 12 to 16 gallons for body plus 2 to 4 for trim.
Skip the arithmetic: use the Paint Calculator.
Key takeaways
- Coverage claims of 350 to 400 sq ft per gallon assume smooth, primed, non-porous surfaces. Real siding rarely is.
- Nearly all exterior work is two coats; a single coat over a color change will not hold its appearance.
- Measure gable ends as triangles: 0.5 x width x height.
- Buy body, trim and accent paint in one trip so each color comes from a consistent batch.
Measuring the paintable area
- Walk the perimeter and add the wall lengths in feet.
- Multiply the perimeter by the wall height from foundation to soffit. A two-story wall is typically 18 to 20 ft.
- Add each gable: 0.5 x gable width x gable peak height.
- Subtract windows and doors — a standard window is about 15 sq ft, an entry door about 21 sq ft.
- Divide the net area by the can's coverage rate, then multiply by the number of coats.
Coverage by surface
The label number is a laboratory figure. What you get depends on how much surface area the texture actually presents and how thirsty it is.
Realistic single-coat coverage per gallon.
| Surface | Sq ft per gallon |
|---|---|
| Smooth fiber cement or previously painted vinyl | 350–400 |
| Smooth wood siding | 325–375 |
| Rough-sawn cedar or T1-11 | 225–275 |
| Stucco | 150–200 |
| Brick or split-face block | 100–150 |
Worked example: a 2,000 sq ft two-story
A 40 ft x 25 ft footprint has a 130 ft perimeter. At 18 ft of wall height that is 2,340 sq ft. Two gables at 25 ft wide and 8 ft tall add 0.5 x 25 x 8 x 2 = 200 sq ft. Gross: 2,540 sq ft.
Deduct 14 windows at 15 sq ft (210) and two doors at 21 (42): net 2,288 sq ft.
On smooth siding at 350 sq ft per gallon, one coat is 6.5 gallons; two coats is 13.1. Buy 14 gallons — three 5-gallon pails is usually cheaper than fourteen singles. On rough cedar at 250 sq ft per gallon, the same house needs 18.3 gallons.
Primer, trim and the extras
- Primer: needed on bare wood, patched areas, chalky surfaces and drastic color changes. Spot-priming may cover only 10 to 20% of the wall.
- Trim and fascia: estimate linear feet x width, or budget 1 gallon per 400 linear feet of typical trim at two coats.
- Soffits and porch ceilings: measure separately; they are often a different sheen.
- Doors and shutters: a quart per door is generous for two coats.
Estimate versus actual
Spraying uses noticeably more paint than brushing and rolling because of overspray and the heavier film it lays down — plan 20 to 30% above the brushed estimate if you spray without back-rolling.
Weather sets the schedule. Most acrylic exteriors specify a surface temperature above 50 F and falling humidity, with no rain for 24 hours. Painting outside those limits is the usual cause of early peeling, and no amount of extra paint fixes it.
Frequently asked questions
How many gallons of paint for a 2,000 square foot house exterior?
Roughly 12 to 16 gallons of body paint for two coats on smooth siding, plus 2 to 4 gallons for trim. Rough cedar or stucco can push the body total past 18 gallons.
Do I need two coats of exterior paint?
Almost always. Two coats give the film thickness the manufacturer's durability rating assumes, and a single coat over any color change will look uneven within a season.
How much does a gallon of exterior paint cover?
About 350 sq ft on smooth, primed siding. Expect 250 on rough-sawn wood, 175 on stucco and as little as 125 on unsealed brick.
Is it cheaper to buy 5-gallon pails?
Usually yes, at a lower price per gallon, and it also guarantees color consistency across the wall. Buy pails for the body color and singles or quarts for trim.
Sources and references
- US EPA — Lead-safe renovation rules (RRP) — Required practices when disturbing paint in pre-1978 homes.
- US Department of Energy — Exterior maintenance and weatherization — Surface preparation and moisture control before coating.