Deck Sealing & Staining Cost Calculator

Frequently asked questions

How much does it cost to stain a deck?

For a 16 by 12 ft deck with 40 ft of railing, a DIY semi-transparent stain job runs roughly $160 to $330 including cleaner and sundries. A contractor typically charges $600 to $1,100 for the same deck in weathered condition, more if an old peeling finish has to be stripped first. Per square foot of coated surface, professional work lands around $2.20 to $3.90.

How much stain do I need for my deck?

Take the deck area, add two square feet for every linear foot of railing, and divide by about 200 square feet per gallon for semi-transparent stain on weathered wood. A 192 square foot deck with 40 ft of railing works out at 272 square feet of surface — two gallons. Buy the extra gallon; running out halfway across a board leaves a permanent lap line.

How often should a deck be resealed?

It depends on the product, not the calendar. Clear water repellents need doing every year, transparent toners every one to two, semi-transparent stains every two to three, solid stains every three to five, and deck paint or a resurfacer every five to eight. Horizontal surfaces in full sun always fail first, so the deck floor will need attention before the railings do.

Do I need to clean a deck before staining it?

Yes, every time. Stain bonds to wood fibre, not to the grey oxidised layer, mill glaze or mildew sitting on top of it, and finish applied over a dirty deck lifts within a season. Wash with a deck cleaner, follow with a brightener if the wood is weathered, and let it dry for at least two clear days before the first coat.