How to Waterproof Wooden Counter Tops

Eva Talent

Wooden countertops, when not waterproofed, are subject to rot and decay -- especially those used in kitchens. Wooden counter tops that are not waterproofed can be damaged by vinegar (which can deteriorate wood glue), hot objects and knives.

Waterproof wooden countertops like this one can be cleaned with hot, soapy water.

However, the correct application of a sealant made of tung oil and resin can prevent decay and keep wooden counter tops looking new for several years. Simply rubbing mineral oil on a wooden counter top will make it water resistant, not waterproof.

  1. Affix a dust mask over your nose and mouth. Sand the countertop using 100- to-150-grit sandpaper. Check for smoothness occasionally and ensure you are sanding evenly.

  2. Vacuum against the grain of the wood to remove dust after sanding. A vacuum attachment with a bristle brush is very effective for wood dust.

  3. Wear rubber gloves. Dip a lint-free cloth in paint thinner and wring it out. Drag the lint-free cloth over the entire countertop to remove any leftover dust. Rinse the cloth periodically if it is picking up large amounts of dust. After each rinse, dip the cloth in paint thinner and wring it out. After the final swipe across the countertop, rinse the cloth and hang it to dry. Wait 15 to 20 minutes before continuing the project to ensure all the paint thinner has dried on the counter top.

  4. Apply one even coat of sealant. Dip a natural-bristled brush in a can of sealant and drag it over the countertop, starting at one end and working your way toward the other. Use a back-and-forth, sweeping stroke after each dip. After covering the entire counter top with sealant, remove your mask and allow the countertop to dry for 24 hours. When 24 hours has elapsed, apply a second coat using the same technique. Allow the second coat to dry for 24 hours. Continue this process until you have reached the number of coats appropriate for the type of wood you have. Most hardwoods require three coats, and most soft woods require four.

  5. Don a protective mask, ensuring it covers your mouth and nose. Apply one coat of finish to the sealed countertop using sweeping, back-and-forth strokes. Once the finish is applied evenly, remove your mask and allow the counter top to dry for 24 hours. If a thicker finish is desired, continue to apply every 24 hours until you have reached the desired thickness. 24 hours is the minimum acceptable drying time between coats.

  6. Warning

    Although finishes appear dry within 24 hours of application, it generally takes two to three months for a finish to set completely. Avoid placing heavy objects on the countertop during this period, because doing so can cause permanent dents. Hot items, such as pots and pans, should also be kept off the countertop.