Paint for an 11 × 12 ft room
This is a secondary bedroom in a newer house. With 8 ft ceilings the four walls have 368 ft² of surface, and after deducting one door (21 ft²) and two windows (30 ft²) there are 317 ft² to paint. The ceiling is 132 ft².
How the number of coats changes it
| Coats | Wall gallons | Buy for walls | Ceiling gallons | Buy for ceiling |
|---|---|---|---|---|
| 1 coat | 0.91 | 1 gallon | 0.38 | 2 quarts |
| 2 coats | 1.81 | 2 gallons | 0.75 | 1 gallon |
| 3 coats | 2.72 | 2 gallons + 3 quarts | 1.13 | 1 gallon + 1 quart |
If your ceilings are taller
| Ceiling height | Wall area | Gallons (2 coats) | Buy |
|---|---|---|---|
| 8 ft ceilings | 368 ft² | 1.81 | 2 gallons |
| 9 ft ceilings | 414 ft² | 2.07 | 2 gallons + 1 quart |
| 10 ft ceilings | 460 ft² | 2.34 | 2 gallons + 2 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 | 2.54 | 2 gallons + 3 quarts |
| 300 ft² per gallon | 2.11 | 2 gallons + 1 quart |
| 350 ft² per gallon | 1.81 | 2 gallons |
| 400 ft² per gallon | 1.59 | 1 gallon + 3 quarts |
Trim, tape and prep
The room is 46 ft around. Taping both the ceiling line and the baseboard is 92 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.
An 11 × 12 room: a newer-house bedroom
An 11 × 12 ft room has 317 sq ft of wall to paint once a door and two windows are taken out, with 132 sq ft overhead. Two coats come to 1.81 gallons for the walls (2 gallons) and 0.75 gallons for the ceiling.
Bedrooms in newer houses usually have smooth drywall with a builder's flat paint on it, which soaks up the first coat of anything shinier. Expect the first coat to look patchy and the second to even it out, and stick with the two-coat figure. If the walls have never been repainted, one coat of primer (0.91 gallons) first gives a better result than a third coat of finish paint.
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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 an 11x12 room?
With 8 ft ceilings, one door, two windows and two coats at 350 ft² per gallon, the walls need 1.81 gallons, so buy 2 gallons. If you also paint the ceiling, add 0.75 gallons (1 gallon).
How much paint for the walls and ceiling of an 11x12 room?
Walls and ceiling together need about 2.57 gallons for two coats. That is 2 gallons + 3 quarts 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 an 11x12 room?
One coat of primer over the same walls is about 0.91 gallons (1 gallon). 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.