How much exterior paint do I need?
Divide the paintable wall area by the paint's spread rate, then multiply by coats. Exterior acrylics list about 300 to 400 sq ft per gallon, less on stucco. A 40 x 28 ft two-story house with smooth siding needs about 12 gallons for two body coats, plus a gallon of trim paint.
Updated · By the Interior Redesign AI editorial team · Sources cited on the page
Body paint to buy
12 gallons
11.6 gal exact: 2,312 sq ft x 2 coats / 400 sq ft per gallon. Trim: 1 gallon.
Trim paint
1 gallon
about 453 ft of trim
Hiring a painter
$7,500-$14,000
Fixr: $2.84-$5.28 per sq ft of wall
| Gross wall area (walls + gables) | 2,644 sq ft |
|---|---|
| Openings | -332 sq ft |
| Paintable body | 2,312 sq ft |
| Spread rate | 400 sq ft per gallon |
| Body gallons | 11.6 |
| Trim area | 189 sq ft |
| Trim gallons | 0.94 |
| To buy | 12 gal + 1 gallon |
Planning estimate. Spread rates come from Benjamin Moore and Behr data (we assume the low end on rough and stucco surfaces); trim length and width are our estimate. Check your paint's label, and buy the body color as one batch.
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Key numbers
- Smooth siding
- 400 sq ft per gallon (top of Benjamin Moore's 300-400 range)
- Rough or textured wood
- 300 sq ft per gallon (low end of the same range)
- Stucco and masonry
- 250 sq ft per gallon (low end of Behr's 250-400 range)
- Coats
- Sherwin-Williams: one coat for repaints, two for unpainted surfaces; we suggest two for a color change
- Hiring a painter
- $2.84-$5.28 per sq ft of exterior wall (Fixr)
Worked example
A 40 x 28 ft two-story house with smooth siding
18 ft walls, two 6/12 gables, 12 windows, 2 doors, a 16 x 7 ft garage door, two coats.
- Gross wall area: 2,448 + 196 (gables) = 2,644 sq ft.
- Paintable body: 2,644 - 332 openings = 2,312 sq ft.
- Body paint: 2,312 x 2 coats / 400 = 11.6 gallons, so buy 12.
- Trim: about 453 ft x 5 in = 189 sq ft x 2 coats / 400 = 0.9 gallon.
- Painter: 2,644 sq ft x $2.84-$5.28 = $7,500-$14,000.
Buy 12 gallons of body paint and 1 gallon of trim; a painter would charge roughly $7,500-$14,000.
How we calculate
Wall area uses the same geometry as our siding calculator: the perimeter times the wall height, plus a triangle for each gable, minus windows, doors and garage doors. The default opening sizes are assumptions; enter your own for a closer count.
Gallons = area x coats / spread rate. Benjamin Moore's Regal Select Exterior data sheet lists 300-400 sq ft per gallon and Behr lists 250-400 for its masonry and stucco paint. Rougher, more porous surfaces drink more paint, so we assume the top of the range on smooth siding, the bottom on rough wood, and Behr's low end on stucco. Your paint's label is the final word.
Trim length is our estimate: casings around windows and doors, fascia along the eaves and the rakes of each gable. We multiply it by a 5 in face width (an assumption you can change) and use the smooth-surface rate. Painter cost applies Fixr's $2.84-$5.28 per sq ft of exterior wall to the full wall area, which is how Fixr measures it.
Estimates, sources
Planning estimates and published guidelines, not quotes, designs or code rulings. Figures were checked on each source on the date shown. Local prices, your home and your jurisdiction's adopted code decide the real answer.
- Regal Select Exterior Soft Gloss 263, technical data sheet (Benjamin Moore, as of Oct 26, 2026): spread rate per gallon 300-400 sq ft; self-priming on most properly prepared substrates (sheet 263 US 091426)
- BEHR Masonry, Stucco & Brick Paint Flat (Behr, as of Oct 26, 2026): 250-400 sq ft coverage per gallon (Behr's product listing; the page refuses automated fetches, so the figure was confirmed from Behr's own listing text in search results)
- Duration Exterior Acrylic Latex (Sherwin-Williams, as of Oct 26, 2026): self-priming: one coat for repaints and two coats for unpainted surfaces
- Cost to paint siding (Fixr, as of Oct 26, 2026): updated Jan 31, 2025: $2.84-$5.28 per sq ft of exterior wall, measured as each wall's width x height added up; 2,000 sq ft of exterior surface $5,675-$10,561
- Vinyl siding estimator (Kaycan, as of Oct 26, 2026): rectangular walls plus triangular gables, windows and doors subtracted from the total surface area, add 10% for waste, 1 square = 100 sq ft
Exterior paint needed by surface
Body paint for the example house (2,312 sq ft of paintable wall), by surface and coats.
| Surface | Spread rate | 1 coat | 2 coats |
|---|---|---|---|
| Smooth siding (vinyl, fiber cement, smooth wood) | 400 sq ft/gal | 6 gal | 12 gal |
| Rough or textured wood (rough-sawn, shakes, T1-11) | 300 sq ft/gal | 8 gal | 16 gal |
| Stucco, brick or block | 250 sq ft/gal | 10 gal | 19 gal |
Should you buy 5-gallon buckets?
For a whole house, usually yes: one batch keeps the color consistent from wall to wall, and painters box (mix) gallons for the same reason. Buy the body color in 5-gallon pails up to the total, then single gallons for the remainder and the trim.
Pro pricing runs $2,840-$5,280 per 1,000 sq ft of wall on Fixr's figures. Prep (scraping, caulking, repairs) and height move a bid more than the paint does.
How to use this tool
Measure the house
Footprint length and width, and the wall height to the soffit.
Add gables and openings
Gable count and roof pitch, then windows, doors and garage doors.
Pick surface and coats
Smooth, rough or stucco; one coat for a same-color repaint, two for a color change or bare surface.
Read the gallons
Body and trim paint to buy, and a painter's cost range.
Questions
How much paint do I need for the outside of a house?
Paintable wall area times coats, divided by about 400 sq ft per gallon on smooth siding, 300 on rough wood or 250 on stucco. A typical two-story house needs 10 to 20 gallons for two coats.
How many gallons of paint for a 2,000 sq ft house exterior?
Floor area is not wall area. A 2,000 sq ft two-story house has roughly 2,000-2,600 sq ft of wall; at two coats and 400 sq ft per gallon that is about 10 to 13 gallons, more on stucco.
How much does a gallon of exterior paint cover?
Benjamin Moore lists 300-400 sq ft per gallon for Regal Select Exterior; Behr lists 250-400 for its masonry and stucco paint. Rough and porous surfaces land at the low end.
Do I need one coat or two on exterior paint?
Sherwin-Williams says one coat of Duration for repaints and two for unpainted surfaces. Plan two for a big color change.
How much trim paint do I need?
Usually 1 to 2 gallons for a house. Add up casings, fascia and rakes, multiply by the board width, and divide by about 400 sq ft per gallon per coat.
How much does it cost to paint a house exterior?
Fixr puts it at $2.84-$5.28 per sq ft of exterior wall, about $5,700-$10,600 for 2,000 sq ft of wall. Height, prep and access change bids most.
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