Estimate interior or exterior painting costs instantly. Enter your project details — we calculate materials, labor, prep, and primer automatically.
Average room = ~400 sqft wall area
Accurate painting estimates depend on measuring paintable surfaces, understanding surface condition, and knowing how many coats you'll need. Most homeowners underestimate the prep work — which often accounts for 50-70% of the total labor.
Step 1: Measure paintable surfaces. For interiors, calculate wall area: perimeter × ceiling height, minus windows and doors (~20 sqft per window, ~21 sqft per door). An average 12×12 room with 9ft ceilings has ~400 sqft of wall area.
Step 2: Assess surface condition. Clean walls in good shape need just a light sand and spot prime. Peeling exteriors may need pressure washing, scraping, and full priming — adding 35-50% to labor costs. New drywall always gets a full prime coat.
Step 3: Count your coats. Standard repaints (same color family) need 2 coats. Going from dark to light (or vice versa) needs a tinted primer plus 2-3 finish coats. Each additional coat adds ~50% to material costs and ~30% to labor.
Step 4: Don't forget trim, ceilings, and prep. Baseboards, crown molding, door frames, and window casings require brush work at $1.50-3.00 per linear foot. Ceiling painting adds roughly 35-40% of wall cost. Tape, drop cloths, plastic sheeting, and masking add up fast.
Interior painting costs $1.50–$3.50 per square foot of wall area, or $1,200–$4,500 for a typical 3-bedroom home. Costs vary by paint quality, surface condition, number of colors, and whether you include ceilings and trim. Cabinet painting costs more — $3,000–$8,000 for a standard kitchen.
Exterior painting costs $2.00–$5.50 per square foot, or $3,000–$12,000 for a typical 2-story home. Two-story homes cost 20–45% more due to scaffolding and ladder work. Surface prep — scraping, pressure washing, caulking, and priming — is often the biggest variable.
One gallon covers roughly 350–400 square feet per coat. A 12×12 room needs 2–3 gallons for 2 coats. Major color changes may need an additional primer coat. Always buy 10–15% extra for touch-ups and waste.
Interior: 1–2 days per room for a professional crew. A whole house interior (3-4 bedrooms) takes 3–5 days. Exterior: 3–7 days depending on size, prep work, and weather. Add 1–2 days for extensive prep (scraping, priming).
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