How Much Paint for a 12×20 Room?
A 12×20 room with standard 8 ft walls has about 512 sq ft of wall — roughly 3 gallons for two coats. Adjust ceiling height and coats below.
Paint to buy
3 gal
Wall area
512 sq ft12×20 room with 8 ft walls
Paint (2 coats)
2.9 gallonsbuy 3 gal — rounding covers doors & windows
Coverage
350 sq ft / gallonper coat, smooth interior surface
Paint cost (est.)
$120~$40/gal mid-grade
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How this is calculated
Mulch volume = bed area × depth. We convert cubic feet to cubic yards for bulk delivery and to 2-cu-ft bags for the bagged option, so you can compare cost both ways.