How to Reseal Your Deck

What you'll need

• Deck sealer/stain
• Applicator pad or brush
• Pressure washer or deck cleaner
• Sandpaper (80-grit)
• Painter's tape
• Drop cloth

The steps

1. 1

   Clean the deck with a pressure washer or deck cleaner

   Remove all furniture, planters, and grills from the deck. Sweep loose debris. Use a pressure washer at 1500 to 2000 PSI with a fan tip held 6 to 8 inches from the surface, working with the grain. If you do not have a pressure washer, scrub with a deck cleaning solution and a stiff bristle brush, then rinse thoroughly with a garden hose. The goal is bare, clean wood with no gray oxidation, mold, or old sealer residue.

2. 2

   Let the deck dry for 48 hours

   The wood must be completely dry before you apply sealer. Moisture trapped under the sealer prevents adhesion and causes peeling within months. Wait a minimum of 48 hours after cleaning. Check the forecast and pick a stretch of dry weather. If rain falls during the drying period, restart the 48-hour clock.

3. 3

   Sand rough spots with 80-grit sandpaper

   Walk the entire deck and feel for splintered or raised grain areas. Sand those spots with 80-grit sandpaper, going with the grain. Pay attention to high-traffic zones like stairs and the area in front of the door. Sweep or blow off all sanding dust before applying sealer.

4. 4

   Stir the sealer thoroughly

   Stir the deck stain and sealer with a paint stick for at least two minutes, scraping the bottom of the can. Pigment settles during storage and an unstirred can produces uneven color. Do not shake the can because shaking introduces air bubbles that leave a rough finish. Stir again every 15 to 20 minutes while you work.

5. 5

   Apply a thin coat with a pad applicator working with the grain

   Use painter's tape to protect the house siding and any surfaces you do not want stained. Lay drop cloths below the deck edges. Dip the applicator pad into the sealer and apply a thin, even coat along the length of each board, working with the grain. Start at the farthest point from your exit and work toward it so you do not step on wet sealer. Avoid puddles. Two thin coats outperform one thick one.

6. 6

   Let the first coat dry for 24 hours before foot traffic

   Keep all foot traffic off the deck for a full 24 hours. Sealer that has not cured will pick up footprints, dust, and debris. Do not replace furniture or planters until the surface is fully dry to the touch and no longer tacky.

7. 7

   Apply a second coat on horizontal surfaces

   Deck floors, stair treads, and railings tops take the most UV and water exposure. Apply a second thin coat to all horizontal surfaces after the first coat has dried 24 hours. Vertical surfaces like balusters and fascia boards typically need only one coat. Let the second coat cure another 24 hours before returning furniture to the deck.

Frequently asked questions

How do I tell if my deck needs resealing?

Do the water bead test. Sprinkle a few drops of water on the deck surface. If the water beads up and sits on top, the sealer is still working. If the water soaks into the wood and darkens it within 30 seconds, the sealer has worn off and it is time to reseal. Test in a high-traffic area because that is where the sealer wears out first.

Can you seal a brand new deck?

Wait 3 to 6 months before sealing a new pressure-treated deck. Fresh pressure-treated lumber is saturated with preservative chemicals and moisture that prevent sealer from penetrating. Let the wood dry and weather slightly. Do the water bead test: when water soaks in rather than beading up, the wood is ready for sealer. New cedar or redwood can be sealed immediately after a light sanding.

Is oil-based or water-based deck sealer better?

Oil-based sealers penetrate deeper and last longer, typically 3 to 5 years. They bring out the natural grain and give a richer look. Water-based sealers are easier to clean up, dry faster, have lower VOCs, and work better in humid climates. They last 1 to 3 years. For most homeowners, a water-based stain and sealer combination is the practical choice because it is easier to apply and recoat.

What is the best time of year to reseal a deck?

Late spring or early fall when temperatures are between 50 and 80 degrees Fahrenheit and rain is not expected for 48 hours. Avoid direct sunlight during application because heat causes the sealer to dry too fast and prevents proper penetration. Early morning or late afternoon on a mild day is ideal. Never apply sealer when temperatures will drop below 50 degrees overnight.

Products you'll need

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