Deck Stain for a 20×20 Deck
A 20×20 deck is 400 sq ft — about 4 gallons of stain for two coats (bare boards drink the first coat). Adjust coats below.
Stain to buy
4 gal
Deck area
400 sq ft
Stain (2 coats)
3.2 gallonsbuy 4 gal
Coverage
250 sq ft / gallonper coat on bare decking
Stain cost (est.)
$140~$35/gal
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