When Do I Seal My Wood Deck?

When New

• The untreated wood of a newly installed deck will quickly weather unless finished with some type of water-repelling product. A clear sealer has several advantages, including allowing the natural look of the wood to remain visible. Sealants typically penetrate into the wood rather than simply forming a film on top of the wood. Finishes that contain large amounts of pigments, such as solid stains, do not work as well as clear sealants, according to the home improvement website Hometips.

Reapply

• When your old sealer has started to let water into the decking, you'll need to reapply a wood-repelling sealer. To test whether the time has arrived for a new treatment, drop a cup of water onto the deck and watch it carefully. If the wood absorbs the water, you need to apply a new coat of sealer. If the water forms droplets on the wood's surface, the old sealer is still functioning properly.

Pressure Wash

• Homeowners who pressure wash their decks risk damaging the wood, according to home improvement expert Tim Carter of the website Ask the Builder. Pressure washers can leave wood decks looking fuzzy and sun damaged. Carter advises repairing wood damaged by high intensity washing by allowing the deck to dry thoroughly and then sanding any wood harmed by the pressure washing. Use aluminum oxide-type sandpaper, and dust off the deck well after sanding. Apply a water-repelling sealer to complete the job. Follow all sealer label directions.

Tips

• Decks have a vulnerability to both mildew and harsh sunlight as well as water. For the most effective protection, choose a sealer that protects your deck from mildew and ultraviolet radiation. Clean the deck prior to applying any sealer, and remove any debris trapped between the wooden boards to prevent mildew. Splash a water and laundry detergent solution on the wood, and scrub the deck with a long-handled brush.