Paint for a 18×20 room
3.2 gallons (buy 3 gal + 1 qt)
for two coats on 557 sq ft of wall: 8 ft ceilings, one door, two windows, 350 sq ft per gallon.
Paint for a 18×20 room by ceiling height
| Ceiling height | Wall area | 1 coat | 2 coats |
|---|---|---|---|
| 8 ft | 557 sq ft | 1.6 gal | 3.2 gal |
| 9 ft | 633 sq ft | 1.8 gal | 3.6 gal |
| 10 ft | 709 sq ft | 2 gal | 4.1 gal |
| 12 ft | 861 sq ft | 2.5 gal | 4.9 gal |
Wall area subtracts one door (21 sq ft) and two windows (15 sq ft each). Ceiling: 360 sq ft, 1.03 gal per coat.
How it’s worked out
- Perimeter: 2 × (20 + 18) = 76 ft.
- Wall area: 76 × 8 ft = 608 sq ft, minus 21 for the door and 30 for the windows = 557 sq ft.
- Two coats: 557 × 2 ÷ 350 = 3.18 gallons.
Change the numbers
Other room sizes
- 18×18 room
- 16×20 room
- 20×20 room
- 15×20 room
- 16×18 room
- 18×24 room
- 14×20 room
- 15×18 room
- 13×20 room
- 14×18 room
- 12×20 room
- 20×24 room
Questions
- How much paint do I need for a 18×20 room?
- About 3.2 gallons for two coats on the walls of a 18×20 room with 8 ft ceilings, one door and two windows: buy 3 gal + 1 qt. The ceiling takes another 1 gallons per coat.
- How many square feet of wall is a 18×20 room?
- 608 sq ft of wall with 8 ft ceilings, or about 557 sq ft after one door and two windows.
- How much does it cost to paint a 18×20 room?
- Paint for the walls costs about $160 at $40 a gallon. Professional painters typically charge $2 to $6 per square foot of floor area, about $720 to $2,160 here.