Paint for a 9 × 9 ft room
This is a child's bedroom or a study. With 8 ft ceilings the four walls have 288 ft² of surface, and after deducting one door (21 ft²) and two windows (30 ft²) there are 237 ft² to paint. The ceiling is 81 ft².
How the number of coats changes it
| Coats | Wall gallons | Buy for walls | Ceiling gallons | Buy for ceiling |
|---|---|---|---|---|
| 1 coat | 0.68 | 3 quarts | 0.23 | 1 quart |
| 2 coats | 1.35 | 1 gallon + 2 quarts | 0.46 | 2 quarts |
| 3 coats | 2.03 | 2 gallons + 1 quart | 0.69 | 3 quarts |
If your ceilings are taller
| Ceiling height | Wall area | Gallons (2 coats) | Buy |
|---|---|---|---|
| 8 ft ceilings | 288 ft² | 1.35 | 1 gallon + 2 quarts |
| 9 ft ceilings | 324 ft² | 1.56 | 1 gallon + 3 quarts |
| 10 ft ceilings | 360 ft² | 1.77 | 2 gallons |
If your walls are rough or your paint covers less
The label on your can gives its coverage. Rough or textured walls and dark colors cover less, so the amounts go up:
| Coverage | Gallons (2 coats) | Buy |
|---|---|---|
| 250 ft² per gallon | 1.90 | 2 gallons |
| 300 ft² per gallon | 1.58 | 1 gallon + 3 quarts |
| 350 ft² per gallon | 1.35 | 1 gallon + 2 quarts |
| 400 ft² per gallon | 1.19 | 1 gallon + 1 quart |
Trim, tape and prep
The room is 36 ft around. Taping both the ceiling line and the baseboard is 72 ft of painter's tape, which is 1 roll of 60 yard tape. A quart of trim paint usually covers the baseboards and window and door casings for a room this size, and a gallon of primer is worth having for stains and patches.
Paint one wall at a time from the ceiling down, "cut in" the edges with a brush before rolling, and keep a wet edge to avoid lap marks. Let the first coat dry fully before the second, as the can directs.
A 9 × 9 room: is the second gallon worth it?
A 9 × 9 ft room has 237 sq ft of wall to paint after one door and two windows, under a ceiling of 81 sq ft. Two coats on the walls come to 1.35 gallons, so the exact purchase is 1 gallon + 2 quarts; the ceiling takes 0.46 gallons.
Two quarts often cost nearly as much as a full gallon, so price both before you decide: a second gallon leaves spare paint for the closet, the back of the door or touch-ups later. If the walls and the ceiling are going the same color, the whole room is 1.82 gallons. In a child's bedroom or a study this size, shelves and a desk hide a good part of one wall, but paint behind them anyway, since furniture moves.
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Tools & materials for this project
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Frequently asked questions
How many gallons of paint do I need for a 9x9 room?
With 8 ft ceilings, one door, two windows and two coats at 350 ft² per gallon, the walls need 1.35 gallons, so buy 1 gallon + 2 quarts. If you also paint the ceiling, add 0.46 gallons (2 quarts).
How much paint for the walls and ceiling of a 9x9 room?
Walls and ceiling together need about 1.82 gallons for two coats. That is 2 gallons if you use the same paint on both, though ceilings are usually painted with a separate flat ceiling paint.
How much primer do I need for a 9x9 room?
One coat of primer over the same walls is about 0.68 gallons (3 quarts). Primer often covers a little less than paint on bare surfaces, so check the can.
Related sizes and guides
Estimates only. Results assume standard materials and simple shapes. Supplier products vary, and the final call on quantity, structure and safety is yours. Check your local code and your supplier's guidance before ordering.