Exterior Paint for a 30×40 House
A 30×40 house with 9 ft walls has about 1,260 sq ft of wall — roughly 9 gallons for two coats. Subtract big windows below for a tighter number.
Paint to buy
9 gal
Wall area
1,260 sq ft30×40 footprint, 9 ft walls (gross)
Paint (2 coats)
8.4 gallonsbuy 9 gal
Coverage
300 sq ft / gallonper coat, exterior surface
Paint cost (est.)
$405~$45/gal exterior
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