How much stain for a 20x20 deck?
A 20x20 deck floor is 400 sq ft. Deck stain covers less than wall paint (~250 sq ft/gal), so two coats need about 3.2 gallons, plus railings and stairs.
Floor, 2 coats
3.2 gallons
400 sq ft of decking.
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🛒 Deck stain & sealer
Weather-resistant stain protects against sun, rain and foot traffic.
Shop deck stain →Frequently asked questions
- How much stain for a 20x20 deck?
- About 3.2 gallons for two coats of the 400 sq ft floor, plus extra for railings and steps.
- How many coats of stain on a deck?
- Two thin coats last longer than one thick coat; high-traffic decks may need a third.