How much paint for a 3,000 sq ft house?
38 gallons of wall paint covers every interior wall of a 3,000 sq ft house twice, at 8 ft ceilings. One coat is 19 gal. The walls of a house carry about 2.2 sq ft of paintable surface per square foot of floor (our factor; halls push it up, open plans pull it down), so 3,000 sq ft of house is roughly 6,600 sq ft of wall.
| Surface | Area | Coats | Buy |
|---|---|---|---|
| All walls | 6,600 sq ft | 1 | 19 gal |
| All walls | 6,600 sq ft | 2 | 38 gal |
| All ceilings (flat white) | 3,000 sq ft | 2 | 17 gal + 1 qt |
| Trim & doors (semi-gloss) | varies | 2 | 2 to 3 gal |
Nobody paints a whole house in one color, and that matters for the shopping list: gallons split across four colors round up four times. If your plan is greige everywhere plus one accent wall and a moody office, price the big color from this page and the small ones with the single-wall calculator.
Questions people ask
Is that every room, or the rooms people actually paint?
Every wall in the house, twice. Real repaints usually skip closets, the garage, and a room or two, so treat 38 gallons as the whole-hog ceiling and subtract rooms you're leaving alone. One 12x12 room is roughly 2 gallons of the total.
How much for ceilings and trim on top?
Ceilings across 3,000 sq ft take about 17 gal + 1 qt of flat white for two coats. Trim, doors, and baseboards for a whole house typically run 1 to 2 gallons of semi-gloss (2 to 3 for a house this size), painted from their own can.
Do 9 ft ceilings change it much?
By 12.5%: wall area scales straight with height. At 9 ft this house carries about 7,425 sq ft of wall and wants 42 gal + 2 qt for two coats. The calculator has a height setting.