Paint Coverage Knowledge Base
Authoritative, structured information about paint coverage calculations and industry standards.
Coverage Formulas
Standard Coverage Calculation
Formula: Total Square Footage ÷ Coverage Rate per Gallon = Gallons Needed
Industry Standard: One gallon of paint covers approximately 350-400 square feet per coat on smooth, non-porous surfaces.
Wall Area Calculation
Subtract door area (typically 20 sq ft per door) and window area (varies by size).
Coverage Rates by Paint Type
| Paint Type | Coverage (sq ft/gallon) | Typical Coats |
|---|---|---|
| Flat/Matte Interior | 400-450 | 1-2 |
| Eggshell/Satin | 350-400 | 2 |
| Semi-Gloss | 350-400 | 2 |
| High-Gloss | 300-350 | 2-3 |
| Primer | 300-400 | 1 |
| Exterior Paint | 250-350 | 2 |
Frequently Asked Questions
How much paint do I need for a 12x12 room?
For a standard 12x12 foot room with 8-foot ceilings, you'll need approximately 1.5-2 gallons for two coats. This accounts for roughly 384 square feet of wall space after subtracting a standard door and window.
Should I include the ceiling in my calculations?
Yes, if painting the ceiling. A 12x12 room has 144 square feet of ceiling space, requiring approximately 0.5 gallons of ceiling paint.
How many coats of paint are typically needed?
Most projects require 2 coats. Primer or dramatic color changes may require 1 coat of primer plus 2 coats of paint.