Q&A: Any tips for refinishing a wood deck?

My 15-year-old pressure-treated-wood deck is in good shape but the opaque finish needs a face-lift. I don’t want to pay a pro, so what’s the easiest way to get the job done?—W. Burks, San Anselmo, CA

Unless the old deck treatment has peeled or flaked, refinishing a deck is definitely a DIY job most homeowners can handle. The work can be tedious, but it’s not tough to do. Since opaque finishes are like paint, the surface simply needs to be free of mildew and clean enough to allow proper adhesion of the next coat. If the old finish is in poor condition with peeling, flaking and cracking, you might want to call in a pro for this more-involved work.

First, choose an alkyd-based or latex-based finish. If you want a water cleanup, use a latex finish. A few alkyds can be cleaned up with water. And stick with the opaque finish to avoid having to sand off the old finish. If you switch to a clear or semitransparent finish and have to scrape or sand any part of the deck, wear adequate protection—gloves, goggles, and a dust mask—and properly dispose of all sawdust and debris. (For more information on working with pressure-treated lumber, read this information from Environmental Protection Agency.)

To find the right finish for your deck, read our latest report on deck stains and refer to our test-based Ratings (available to subscribers).

Plan your work when the weather forecast calls for an extended period of dry weather. Then follow these steps:

• Remove all furniture, planters, and other objects from the deck. Sweep off any debris or leaves. Protect plantings around the deck by covering them with a plastic tarp. And use painter’s tape to keep the finish off walls or other adjacent surfaces.

• With a stiff bristle brush attached to a long handle, apply a cleaning solution across the entire deck. Use a store-bought product or make your own: Carefully add 1 quart of bleach to a large bucket filled with 3 of quarts water. Follow the manufacturer's instructions for application.

• Get out your pressure washer to rid the deck of mildew and other stains. Using a wide spray pattern, begin with the nozzle 2 feet away and move closer as needed, but no closer than 6 inches to avoid damaging the wood. Wash the entire deck. If you don’t have a pressure washer, use a garden hose with a sprayer attachment. Let the deck dry for a few days before applying the new finish.

• To apply the finish, brush deck boards one at a time following the grain. Be careful to not allow any pools to form. Avoid brush marks by applying the finish from wet areas to dry areas. If you use a roller, follow up with a brush to work in the treatment.

• Use as many coats as the manufacturer recommends.

• If you’re going to apply a second coat, check the label for drying time between coats. Let the final coat dry for at least 72 hours before walking on it or replacing the furniture and planters.

Send your questions about deck treatments or any other home-related topic to our experts.

Comments

[Ed Burke]

The advice of experts who know more about wood, and wood use than anyone conflicts with the advice above. I belong to the Joint Coatings/Forest Products Committee at the USDA's Forest Products Laboratory (www.FPL.FS.FED.US). The senior scientist in charge of the work unit responsible for the study of wood finishing and maintenance warns that wood decks should NOT be coated with a 'Film-Forming' coating. Such coatings can cause decay in wood decks by trapping moisture in the deck planks. Film-Forming finishes are: Varnish, Shellac, Lacquers, Paints, and solid Opaque stains.

Wood decks need to dry out between rain storms, which is why a space exists between properly installed deck boards, and old homes with front porches have lattice work beneath the floor. If water becomes trapped in the wood and it remains saturated the wood will begin to decay.

[Curt Kelly]

Are there any additives, maybe sand ? to help an area next to a pool
to reduce slipping ?

[Zelle]

How do you do you remove the sealer that was inadvertently sprayed on the small concrete patio and brick steps next to the deck?

Zelle

[builder]

Short and sweet, this is what I do. Mix bleach 50/50 with water pump spray on deck and let sit only about 5 minutes (dont let dry) and pressure wash off. Thats how I clean my deck.