Ten Steps for Prepping A Deck For Stain
Prep a deck for stain
Preparing an old deck for stain is easy; chemicals do most of the work. But it’s not a job that allows for shortcuts. If you break a few basic rules, your finish will fail fast and you’ll be back for a redo. Here’s how to do it right.
Step One: Test the existing stain
Water-based (acrylic) stains must be stripped off before you apply a new finish, while oil-based stains can be recoated after you use a deck cleaner. So, your first step is to determine which type of stain is on the deck. Apply a small amount of deck stripper to an inconspicuous spot. Let it sit for about 15 minutes, then wipe it off. If the stain comes off, the stain is a water-based product and you’ll have to strip it off. If the stain doesn’t come off, it’s an oil-based product that can be recoated with an oil-based deck stain once properly cleaned. If you have a deck that’s never been stained, just go right to the steps eight and nine.
Step Two: Protect plants and siding
Deck stripper and cleaner can kill grass and plants. Protect vegetation with a fabric drop cloth or light-colored tarp. (Clear plastic sheeting will trap heat from the sun and fry your plants.) Then wet down the siding near the deck using your garden hose. Wet surfaces are less likely to be damaged by splashes of stripper. Clean off all loose deck debris with a push broom or leaf blower.
Step Three: Apply the stripper
Shake the deck stripper and pour it into a paint tray. Working in small sections, roll on a thick coating using a 1/2-in. or 3/4-in. nap roller and an extension pole. Use a paintbrush to get stripper on areas that can’t be reached with the roller. If you splash stripper onto your siding, wash it off right away.
Step Four: Keep the stripper damp
Let the stripper work its magic for 15 minutes. If the stripper starts to dry during this period, keep it damp with water from a pump-up sprayer.
Step Five: Scrub away the dissolved stain
Scrub with a stiff-bristle broom. If you have thick layers of stain, you may need to scrape off the residue with a floor scraper first. If that’s the case, you’ll likely have to reapply more stripper for the scrubbing step.
Step Six: Power-wash the stripper
Rinse off the stripper and dissolved stain using a stiff stream from a garden hose nozzle, or a pressure washer on the lowest setting. A pressure washer makes the job much easier. If you only have a garden hose, you’ll have to scrub more as you rinse.
Step Seven: Sand the stubborn spots
Let the deck dry. Areas that need additional treatment will be obvious. Repeat the stripping/scrubbing routine on those spots. If there’s no improvement after a few rounds, sand those areas with a random orbital sander.
Step Eight: Clean and neutralize the deck
Clean the deck with a deck cleaner. Mix a 50/50 solution of water and cleaner if your wood is reasonably clean. For extremely weathered boards, try the cleaner at full strength. Experiment with a small area to determine which is better. Wet the wood with your garden hose and apply a liberal coating of the cleaner using a pump sprayer. Let the cleaner sit for 10 to 15 minutes and keep it damp before scrubbing with a stiff-bristle broom. Then rinse the entire deck and let it dry.
Step Nine: Sand away the burrs
The cleaning step will raise lots of small fibers. After the deck dries to the touch, lightly sand the deck with a drywall sanding pad and 100-grit sanding screen. That’ll knock down any raised wood fibers and give your deck a much smoother finish. Blow the sanding dust off with a leaf blower, and after a couple days of dry weather, you’ll be ready to stain.
Step Ten: Make the stain last!
Follow the directions on the can. Typically, the surface of the wood should be completely dry, and the stain should be applied in temperatures between 40 and 90 degrees F. Check the forecast and don’t apply stain if rain is expected within 24 hours.