How You Can Waterproof Your Deck

Your deck is exposed to every element outside, the sun, wind, rain, and maybe even the snow, not to mention the wear and tear your deck takes just from walking across it. If your deck is starting to show some wear and tear, you are going to need to do some work to it to get it looking like new again. Waterproofing your deck is one thing you can do to prevent your deck from showing too much wear. Read on for instructions to help you waterproof your deck.

What You'll Need: 

  • A pressure washer or garden hose
  • Scrub brush
  • Deck wash
  • Sanding block or palm sander
  • Deck waterproofing paint or clear coat
  • Paintbrush
  • Roller and extension pole


1. First, you need to remove everything from the deck so you have a clear area to work with. You may end up with dirt being sprayed on your patio furniture, so move everything out of the way and far enough away so you don't ruin your patio furniture.

2. Next, spray your deck with either the garden hose or the pressure washer. If you are using a pressure washer, you need to set it to a lower setting so it doesn't strip your wood and cause damage to your wood.

3. Use a deck wash to thoroughly clean the wood and remove mold and mildew. When using a deck wash, you're going to need to use a scrub brush as well to get in between the wood slats and in the grooves of the wood as well. Rinse your deck thoroughly to remove the cleaner. If you have cleaner on the deck, your waterproofing paint or clear coat isn't going to adhere properly.

4. Once your deck is completely clean, you need to allow it to dry before you begin waterproofing. Give it at least 24 hours to dry out. If it's splintered or needs to be sanded in any area, use the sanding block or palm sander to sand the deck.

5. Finally, take your waterproofing paint or clear coat and apply it using your paintbrush and roller with an extension pole. Use the paintbrush to get in between the wood slats and along the edges of your deck. Then use the roller and pole to roll the waterproofing paint on your deck. Apply the waterproofing paint evenly, then allow it to dry. Apply a second coat if necessary for more coverage. Don't put anything back on the deck until it's completely dry and set—at least 48 hours.

If your deck is starting to show wear, it can be cleaned and waterproofed to make it last longer and look new again. Hire a deck waterproofing contractor to do this work for you, as it can be a big job.