How Much Paint for a 15x15 Room?
A 15×15 ft room with 8 ft ceilings has 430 sq ft of paintable wall. Two coats take 2.46 gallons, so buy 3 gallons of wall paint. Adding the ceiling brings the total to 3.74 gallons (4 gallons).
Paint needed for a 15x15 room
| Scenario | Paintable area | Exact gallons | Buy |
|---|---|---|---|
| Walls, 1 coat | 430 sq ft | 1.23 | 2 gallons |
| Walls, 2 coats | 430 sq ft | 2.46 | 3 gallons |
| Ceiling, 2 coats | 225 sq ft | 1.29 | 2 gallons |
| Walls + ceiling, 2 coats | 655 sq ft | 3.74 | 4 gallons |
| Walls, 2 coats, 9 ft ceiling | 490 sq ft | 2.8 | 3 gallons |
Assumes 1 door (20 sq ft) and 2 windows (15 sq ft each) deducted, 350 sq ft per gallon, 8 ft ceiling unless stated. Trim and doors not included.
How it is calculated
Walls: 2 × (15 + 15) × 8 = 480 sq ft
Minus door and windows: 480 − 50 = 430 sq ft
Two coats: 430 × 2 ÷ 350 = 2.46 gallons → 3 gallons
Ceiling: 15 × 15 = 225 sq ft → 225 × 2 ÷ 350 = 1.29 gallons
Tips for a 15x15 room
- You need 2.46 gallons, so 3 gallons leaves about 2.2 quarts spare – enough for touch-ups. Do not bother with a 5-gallon bucket.
- Cutting in with a brush runs 60 ft along the ceiling line and another 60 ft along the baseboards, before counting door and window frames.
- The 225 sq ft ceiling is large enough to justify a roller extension pole and a dedicated ceiling paint – count on 2 gallons for two coats.
Frequently asked questions
How many gallons of paint for a 15x15 room?
With 8 ft ceilings the walls total 2 × (15 + 15) × 8 = 480 sq ft. After deducting 50 sq ft for one door and two windows, 430 sq ft remain. Two coats at 350 sq ft per gallon is 2.46 gallons, so buy 3 gallons. One coat needs 1.23 gallons.
How much paint for the walls and ceiling of a 15x15 room?
The ceiling adds 225 sq ft. Walls plus ceiling, two coats, comes to 3.74 gallons, so buy 4 gallons. The ceiling alone needs 1.29 gallons for two coats.
How much does it cost to paint a 15x15 room?
Paint for the walls (3 gallons) costs roughly $75–$180 at $25–$60 per gallon. With 9 ft ceilings you would need 2.8 gallons, so 3 gallons. Primer, tape and supplies are extra.