Paint for a 13 × 13 ft room
This is a generous bedroom or a small living room. With 8 ft ceilings the four walls have 416 ft² of surface, and after deducting one door (21 ft²) and two windows (30 ft²) there are 365 ft² to paint. The ceiling is 169 ft².
How the number of coats changes it
| Coats | Wall gallons | Buy for walls | Ceiling gallons | Buy for ceiling |
|---|---|---|---|---|
| 1 coat | 1.04 | 1 gallon + 1 quart | 0.48 | 2 quarts |
| 2 coats | 2.09 | 2 gallons + 1 quart | 0.97 | 1 gallon |
| 3 coats | 3.13 | 3 gallons + 1 quart | 1.45 | 1 gallon + 2 quarts |
If your ceilings are taller
| Ceiling height | Wall area | Gallons (2 coats) | Buy |
|---|---|---|---|
| 8 ft ceilings | 416 ft² | 2.09 | 2 gallons + 1 quart |
| 9 ft ceilings | 468 ft² | 2.38 | 2 gallons + 2 quarts |
| 10 ft ceilings | 520 ft² | 2.68 | 2 gallons + 3 quarts |
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 | 2.92 | 3 gallons |
| 300 ft² per gallon | 2.43 | 2 gallons + 2 quarts |
| 350 ft² per gallon | 2.09 | 2 gallons + 1 quart |
| 400 ft² per gallon | 1.83 | 2 gallons |
Trim, tape and prep
The room is 52 ft around. Taping both the ceiling line and the baseboard is 104 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 13 × 13 room: each coat is slightly more than a gallon
A 13 × 13 ft room has 365 sq ft of paintable wall after a door and two windows, and a 169 sq ft ceiling. Two coats on the walls need 2.09 gallons, bought as 2 gallons + 1 quart, and the ceiling 0.97 gallons.
One coat on these walls is 1.04 gallons, so a single can does not quite finish a coat at the 350 sq ft per gallon used here. A paint with a higher spread rate on its label can bring the whole job under two cans, and a rough wall pushes it the other way; the coverage table above shows both cases. With walls and ceiling together at 3.05 gallons, this is a room where it pays to read the can before choosing between quarts and a third gallon.
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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 13x13 room?
With 8 ft ceilings, one door, two windows and two coats at 350 ft² per gallon, the walls need 2.09 gallons, so buy 2 gallons + 1 quart. If you also paint the ceiling, add 0.97 gallons (1 gallon).
How much paint for the walls and ceiling of a 13x13 room?
Walls and ceiling together need about 3.05 gallons for two coats. That is 3 gallons + 1 quart 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 13x13 room?
One coat of primer over the same walls is about 1.04 gallons (1 gallon + 1 quart). 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.