Short answer
Painting the exterior of a stucco house with a 150 ft perimeter, 10 ft walls, 2 doors, and 10 windows takes approximately 9 gallons of body paint for two coats. That's based on 1,308 sq ft of paintable wall area and stucco's 1.2 siding factor — the rough texture demands about 20% more paint than smooth siding. You'll also need 5 quarts for trim and about 3.7 gallons of primer if starting from bare or unpainted stucco.
How this calculator works
The calculator follows a straightforward gross-area-minus-openings approach, adjusted for surface texture and number of coats.
Step 1: Calculate gross wall area
Multiply house perimeter by wall height:
150 ft × 10 ft = 1,500 sq ft
This is the total envelope before any deductions.
Step 2: Subtract doors and windows
Each exterior door is treated as 21 sq ft (a standard 3×7 door with frame). Each window is treated as 15 sq ft (a typical double-hung). The calculator deducts these from gross area:
1,500 sq ft − (2 doors × 21 sq ft) − (10 windows × 15 sq ft) = 1,500 − 42 − 150 = 1,308 sq ft paintable area
If you have unusually large picture windows or sliding glass doors, bump the window count up by one for every extra 15 sq ft above standard size.
Step 3: Apply the siding factor
Smooth siding gets a factor of 1.0. Vinyl lap siding gets 1.1. Stucco and cedar shake — both textured, porous surfaces — get 1.2. The factor scales up the effective area the paint has to cover:
1,308 sq ft × 1.2 = 1,569.6 effective sq ft
Step 4: Multiply by number of coats
Two coats doubles the material needed:
1,569.6 × 2 = 3,139.2 sq ft total coverage required
Step 5: Divide by 350 sq ft per gallon
The calculator uses 350 sq ft/gallon rather than the 400 sq ft/gallon printed on most cans. The 400 sq ft figure is a spread rate measured under lab conditions. In the field — especially on textured stucco — absorption and application losses bring real coverage closer to 350 sq ft. Using the optimistic can rate is one of the most common reasons homeowners run short mid-project.
3,139.2 ÷ 350 = 8.97 gallons, rounded up to 9 gallons
Secondary outputs
The calculator also estimates:
- Primer: ~3.7 gallons for a single primer coat over the 1,308 sq ft. Use a masonry bonding primer formulated for stucco — standard drywall primer won't handle the alkalinity.
- Trim paint: 5 quarts, based on 1 quart per 30 linear ft of trim. Trim paint is a separate purchase because it's a different sheen and often a different color.
What the output doesn't cover
The calculator handles body paint on flat wall surfaces. It does not estimate paint for soffits, fascia, columns, or decorative corbels — those surfaces add material and should be measured separately. If your stucco is unpainted or severely faded, expect the first coat to absorb heavily; some painters apply a third coat or a specialty fill primer on weathered surfaces before counting it as a two-coat job.
Adjusting for your project
Perimeter is the most important input to get right. Walk the house and measure each wall face with a tape, then add all four (or more) sides. Don't estimate off square footage — a 1,400 sq ft house can have a perimeter anywhere from 150 ft to 200 ft depending on how the floor plan is shaped.
Recommended materials
For stucco, paint film thickness and adhesion matter more than on smooth siding, so quality of product pays off. A 100% acrylic exterior paint rated for masonry surfaces holds up best against stucco's moisture absorption and thermal movement. An airless sprayer dramatically reduces labor time on textured surfaces, and back-rolling immediately after spraying ensures full penetration. For anything above one story, a proper extension ladder is non-negotiable — scaffolding or pump jacks are worth renting for whole-house jobs.
- Behr Marquee exterior paint (1 gallon) — a 100% acrylic formula with masonry-appropriate film build; rated for direct-to-stucco application
- Graco Magnum X5 airless paint sprayer — handles the viscosity of exterior masonry paints without thinning; strongly recommended for stucco over rolling alone
- Werner D1224-2 24-foot aluminum extension ladder — reaches 10 ft walls at a safe working angle with room to move along the fascia line
FAQ
How many gallons of paint does a stucco house exterior need? A 1,400 sq ft stucco home with a 150 ft perimeter, 10 ft walls, 2 doors, and 10 windows needs roughly 9 gallons of body paint for two coats. Stucco's rough texture requires a 1.2 siding factor, so you'll use about 20% more paint than a smooth surface of the same size.
Why does stucco need more paint than other siding? Stucco has a porous, textured surface that soaks up more paint and requires deeper penetration to achieve an even finish. The standard siding factor for stucco is 1.2, meaning you need 20% more paint compared to smooth siding at the same square footage.
Do I need primer on stucco before painting? Yes, in most cases. New or bare stucco is highly alkaline and porous, so a masonry primer seals the surface and improves paint adhesion. For this example home, expect to use about 3.7 gallons of primer for a single primer coat.
How does the calculator account for doors and windows? The calculator subtracts 21 sq ft per exterior door and 15 sq ft per standard window from the total gross wall area. This keeps your paint estimate realistic and prevents over-ordering.
How many coats of paint does exterior stucco need? Two coats is the minimum for full, even coverage on stucco. If you're making a dramatic color change or painting bare stucco for the first time, a primer coat plus two finish coats gives the most durable result.
How much trim paint do I need separately? The calculator estimates 1 quart of trim paint per 30 linear feet of trim. For a 150 ft perimeter house, that works out to 5 quarts. Trim paint is typically a different sheen (semi-gloss or gloss), so it should be purchased and applied separately from the body paint.
Should I spray or roll stucco? Spraying is faster and forces paint into the texture more effectively. Rolling after spraying — a technique called 'spray and back-roll' — is the professional standard for stucco because it ensures the paint bonds to the uneven surface and minimizes holidays (missed spots).
What coverage rate does this calculator use? The formula uses 350 sq ft per gallon, which is a realistic field coverage rate for exterior paint on textured surfaces. Most paint cans list 400 sq ft per gallon, but that assumes ideal conditions. The lower rate accounts for texture absorption and brush-out losses.
Does the 9-gallon estimate include a waste factor? The main output does not add a separate waste percentage on top — the 350 sq ft/gallon coverage rate already builds in real-world usage. If you are spraying without back-rolling, add 10–15% more paint for overspray losses.
How do I calculate paint for a two-story stucco house? Enter the full perimeter and the total wall height, which for a two-story house is typically 18–20 ft. The calculator multiplies perimeter by height to get gross wall area before subtracting openings, so it handles two-story homes correctly as long as you enter the correct height.
Can I use interior paint on exterior stucco? No. Interior paints lack the UV inhibitors, mold resistance, and flexibility needed to handle temperature swings and weather exposure. Always use a paint labeled specifically for exterior masonry or stucco surfaces.