Exterior Paint Calculator
Exterior painting covers far more area than a single room, and rough surfaces drink paint. Enter the total wall area of your house, set the number of coats, and the calculator estimates the gallons needed — using a lower coverage rate than interior walls, because siding, stucco and brick absorb more.
Area to paint
301 sq ft
Gallons needed
2 gal
Quarts needed
7 qt
Estimated paint cost: $90.00 (2 gallons at $45.00 each)
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How to use this paint calculator
- Enter the room length, width and wall height.
- Set the number of coats — 2 is typical for a colour change.
- Enter how many doors and windows the room has.
- Tick 'include ceiling' if you are painting the ceiling too.
- Adjust the coverage rate if your paint can states a different figure.
- Read the gallons needed, quarts needed and the estimated cost.
Frequently asked questions
How much paint do I need for a house exterior?
A single-storey 1,500 sq ft home typically has 3,000–4,000 sq ft of paintable wall area after windows and doors. At two coats and 300 sq ft per gallon on smooth siding, that is roughly 20–27 gallons.
What coverage rate should I use for exterior surfaces?
Use about 300 sq ft per gallon on smooth siding or stucco, and closer to 250 on brick or rough-sawn wood. Always check the paint can — premium exterior paints often state a higher coverage.
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