Painting a whole house interior is the project where “a few gallons” quietly becomes sixteen. This guide prices the full job for a 1,500 sq ft house before you start: how much wall there actually is to paint, exactly what belongs on the shopping list, and what the materials add up to at typical US prices.
The assumptions, up front. A single-story 1,500 sq ft house with 8 ft ceilings, in good condition with previously painted walls. The estimate covers walls only — no ceilings, trim, or doors — with two coats of standard interior latex and spot-priming only where patches or repairs need it. If your house differs, the same math is built into the calculator further down this page.
How much wall is in a 1,500 sq ft house?
More than most people expect, because interior walls get painted on both sides:
- Exterior walls: a 50 × 30 ft footprint has a 160 ft perimeter; 160 × 8 ft ceilings = 1,280 sq ft.
- Interior partitions: roughly 120 linear ft of room dividers, painted on both sides; 120 × 8 × 2 = 1,920 sq ft.
- Gross wall area: about 3,200 sq ft.
- Openings: a dozen doors and a typical set of windows subtract roughly 400 sq ft.
- Paintable wall area: about 2,800 sq ft.
At the standard coverage of 350 sq ft per gallon per coat, that is 2,800 ÷ 350 = 8 gallons per coat — 16 gallons for two coats. Taller ceilings, a two-story foyer, or lots of partition walls push the number up; the Paint Coverage Chart: How Much Paint per Square Foot shows the same math for other sizes.
Materials list and cost
Typical US prices, checked November 2026 — the same figures used on our Paint Calculator page. Materials only.
| Item | Quantity | Typical cost |
|---|---|---|
| Interior wall paint, standard latex | 16 gallons | $400 – $720 ($25 – $45 per gallon) |
| Primer (spot-priming patches and repairs) | 1 – 2 gallons | $15 – $60 ($15 – $30 per gallon) |
| Painter’s tape, 1.5 in | 3 – 4 rolls | $15 – $32 |
| Roller covers, frames, trays, and liners | House set | $30 – $50 |
| Drop cloths | 2 – 3 | $20 – $45 |
| Brushes, filler, sandpaper, and caulk | Assorted | $25 – $45 |
Total cost
Paint and supplies come to about $500 – $950 for the walls of a 1,500 sq ft house. The paint itself is most of it: switching to premium paint at $45 – $70 a gallon pushes the 16 gallons alone to $720 – $1,120 and the total to roughly $800 – $1,350. A full primer coat over every wall — only needed for bare drywall or a dramatic color change — adds another 8 gallons of primer, about $120 – $240.
Hiring it out instead: at the $1.50 – $3.50 per sq ft of wall (materials and labor) from our Interior Paint Cost per Square Foot (2026 Guide), a professional job on 2,800 sq ft of wall totals about $4,200 – $9,800, walls only — roughly $2.80 – $6.50 per sq ft of floor area, which is how most painters quote whole houses. The DIY saving is several thousand dollars; the cost is several weekends.
What is not included
- Ceilings. A 1,500 sq ft ceiling at 350 sq ft per gallon takes about 5 gallons per coat, plus ceiling paint is usually a separate, flatter product.
- Trim and doors. Baseboards, casing, and doors are commonly a separate line in pro quotes and a separate weekend in DIY ones.
- Repairs. Cracked drywall, water stains, and wallpaper removal all add time and material before any paint is opened.
Calculate your own project
Different footprint, higher ceilings, or ceilings and trim in scope? Our Paint Calculator runs the same calculation with your measurements — wall area, openings, coats, and a coverage rate you can lower for textured walls.
The job in six steps
- Clear and cover: move furniture to the center or out, cover floors end to end, and remove switch plates and vent covers.
- Wash and repair: wipe down walls, fill nail holes and dings, let filler dry, sand smooth, and spot-prime every repair so it does not flash through the finish coats.
- Mask: tape baseboards, trim, and ceiling lines room by room, just ahead of painting each one.
- First coat: cut in edges with a brush, then roll, working one wall at a time and keeping a wet edge.
- Second coat after the recoat time printed on the can — usually 2–4 hours — applied the same way.
- Finish: pull tape while the last coat is still slightly wet for clean lines, and keep a labeled quart of leftover paint for touch-ups.
FAQ
How many gallons of paint do I need for a 1,500 sq ft house interior?
About 16 gallons for the walls: roughly 2,800 sq ft of paintable wall, divided by the standard 350 sq ft per gallon, is 8 gallons per coat, doubled for two coats. Add about 5 gallons per coat if the ceilings are in scope.
How much does a professional charge to paint a 1,500 sq ft house interior?
Typically $4,200 – $9,800 for walls only, based on $1.50 – $3.50 per sq ft of wall area including paint. Ceilings, trim, heavy prep, and high ceilings all move the quote up.
Why is the wall area so much bigger than the floor area?
Interior partition walls are painted on both sides, so a whole house ends up with roughly twice its floor area in wall — here, about 2,800 sq ft of paintable wall in a 1,500 sq ft house, after openings are subtracted. Single rooms run higher still, around three times the floor area at 8 ft ceilings.
How long does it take to paint a whole house interior?
A professional crew commonly finishes in 2–4 days. DIY, working room by room around furniture, most people spread it over several weekends — which is also why so many whole-house jobs get done one room at a time.
Is one coat ever enough?
Sometimes — same color, similar sheen, walls in good condition, and a quality paint. Budget and buy for two coats regardless; a same-color repaint that covers in one leaves you a gallon ahead for touch-ups instead of one short on a Sunday.
Related guides and calculators
Start smaller if you prefer: the Cost to Paint a 12×12 Bedroom: Materials & Cost prices a single room the same way, the Interior Paint Cost per Square Foot (2026 Guide) breaks down rates by the square foot, and the Paint Calculator works out gallons for any room you measure.
Estimates only. Prices are typical US ranges checked in November 2026 and vary widely by region, product, and contractor. Confirm current prices and get written quotes before committing to a project.