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Protect Your Deck with The Thompson’s Water Seal

You’ve just installed your dream deck and now you need to seal it with a product that is easy to apply and provides superior protection from the elements. Perhaps Thompson’s Water Seal products are just what you’re looking for.

thompson water sealView in gallery

Keep on reading as we learn about the Thompson Brand, its products, and how it compares to other brands out there. We’ll even give you some quick tips for staining your deck as well as links to more in-depth instructions. So, let’s jump right in and see if Thompson’s Water Seal is the right product for you.

About the Thompsons’ Brand

Developed by polymer chemist Edward Addis Thompson in the early 1920s, the Thompson brand of water sealers was originally used to seal concrete and protect it from water damage. Over the years the product line expanded to include water seals suitable for a variety of construction materials and in 1982 the company expanded its distribution to residential consumers. Today, the Thompson line includes waterproofing products for an array of materials as well as waterproofing stain and sealer mixes and specialized cleaning products.

The Thompson brand takes pride in creating new technologies designed to limit negative impacts on the environment while maintaining the high standard of products they are known for. They also maintain an active role in the community and openly support the Big Brothers Big Sisters program, The Hole in the Wall Gang Camp for Sick Kids, and the Pacific Marine Mammal Center, which rescues and rehabilitates sick and injured seals and sea lions.

What is a Water Sealer?

thompson's water seal clearView in gallery

A water sealer is a type of stain that provides waterproofing and weather protection on exterior surfaces such as wood, stone, concrete, brick, and mortar. It is a silicone micro-emulsion formula that absorbs into the surface of a material and protects it against water damage.

Sealers come in three categories: transparent (or clear) sealers, semi-transparent stain, and solid stain. While all deck stains are technically sealers, they don’t all do the same job.

Transparent sealers (also known as water sealers) are basically designed solely for protection against water damage. They maintain the natural color of the surface they are applied to, but they don’t offer UV protection to that surface. This could lead to discoloration over time.

Semi-transparent stains add a bit of color to the surface they are applied to and provide an adequate amount of UV protection along with the standard waterproofing protection of most sealers. Semi-transparent stains/sealers are the most used for deck and patio applications because they offer better UV protection than transparent sealers while still maintaining the appearance of natural wood.

Solid stain is almost like paint and provides the best UV protection along with waterproofing properties. The downside to solid stain sealers is that the natural grain of the wood surface is covered completely.

Best choice
Thompson's Water Seal
Thompson's Water Seal

Applying Thompson’s water seal to your deck and other outdoor surfaces is an important step in keeping them safe from environmental damage and beautiful for years to come.

View Deal

Thompson Water Seals

Thompson Water SealsView in gallery

They’re designed specifically to prevent water damage to decks and other exterior surfaces. The semi-transparent and solid stains in this line also protect from mildew and UV damage. Made with advanced polymers, these stains have fade-resistant color and can be applied to dry or damp wood. Thompson’s Water Seal also exceeds the Industry Standard for its ability to provide waterproofing to wood.

When Should I Use a Thompson’s Water Seal?

When Should I Use a Thompson’s Water Seal?View in gallery

You should always take the time to seal, or water seal, any exterior surface as soon as it is built. This will help extend the life of the surface and help to keep its colors vibrant.

After the first application, you should be re-sealing every one to three years depending on the surface being sealed, the weather conditions in your area, sun exposure, and the sealing product itself.

Other factors to consider when applying water sealers include:

  • The air temperature as well as the temperature of the material being sealed,
    • For a clear water sealer, the air and surface temperatures need to be ten degrees Celsius.
    • Stain/sealers require the air and surface temperatures to be between ten and thirty-five degrees Celsius.
  • The weather forecast for the days following the anticipated application day,
    • It is important that there be no rain in the forecast for at least 24 hours post-application.
  • Time of day,
    • It is best to apply sealers, especially stains when the surface they are being applied to is not in direct sunlight.

It is always important to follow the manufacturer’s recommendations when applying any transparent or non-transparent sealer to any surface.

How to Apply Thompson’s Water Seal

How to Apply Thompson’s Water Seal

Most water sealers require a single coat and can easily be applied by the average DIYer. Although water sealers can be used on a variety of surfaces, we will focus on decks for the purpose of this section. Here are some basic guidelines to remember when applying water sealer.

Make sure to protect the area around and under the deck. Cover vegetation, walls, windows, and other surfaces with a tarp or some other type of plastic sheeting.

Once everything is protected, sweep the deck, ensuring it is clear of all dust and debris. Pour an appropriate cleaner into a spray bottle and start the cleaning process with the railing and balusters. Allow the cleaner to sit for around ten minutes but be sure to not let it dry. After the cleaner has been left to soak, wipe the loosened dirt from the surface and spray the area with clear water to rinse. Repeat this step on the deck boards and allow them to dry for forty-eight hours.

Check the deck surface for splinters, raised fasteners, and other hazards and remove them prior to applying the seal. If splinters need to be sanded off, ensure that the loose particles are removed.

Starting with the railing and balusters, follow the manufacturer’s recommendations for applying the sealer. Once complete, follow those same steps to apply a sealer to the deck boards. Let the sealer dry for a minimum of twenty-four to forty-eight hours before returning furniture to its spot or using the deck surface.

Thompson’s VS Other Brands of Water Seal

Thompson’s VS Other Brands of Water Seal

Thompson’s brand of water sealers is well known and available locally at most hardware stores. It provides UV resistance and is 100% waterproof. This maximum strength brand can be applied to dry or damp wood and often needs only a single coat. The sealer is easy to clean and is available in a variety of colors including transparent – which provides protection while maintaining the wood’s natural beauty. The two biggest drawbacks to the Thompson brand are that it tends to be slippery when it’s wet and its UV protection is lacking, even in its semi-transparent and opaque formulas.

Competitor brands of water sealers are generally comparable to Thompson’s with just a few notable differences. The biggest of which is their ability to protect surfaces from UV damage. It seems that although the Thompson brand is the leader in several categories, it doesn’t make the cut when it comes to UV protection. Especially when referring to their transparent sealers. There is a trade-off, however, as some of the brands boasting the highest UV protection have other major drawbacks such as requiring large quantities to cover new wood, being only available in a clear finish, or only being suitable for composite decks.

As with many products, it is important to do the research to find out what is available and what will be the best product for your project.

What Colors are Available in Thompson’s Water Seal?

Thompson’s Water Seal comes in a variety of colors and protection coverage to suit any application.

Their Signature Series Transparent and Semi-Transparent Stain/Sealer comes in Autumn Brown, Natural Cedar, Honey Gold, and Timber Brown. Their Signature Series Solid Stain/Sealer comes in Autumn Brown, Natural Cedar, and Timber Brown.

What Colors are Available in Thompson’s Water Seal?

Thompson’s Water Sealer Waterproofer Plus Tinted and Semi-Transparent Wood Stain/Sealers come in Natural Cedar, Desert Brown, Nutmeg Brown, and Rustic Red.

The Waterproofing Stain comes in transparent, semi-transparent, and solid options in Sequoia Red, Acorn Brown, Maple Brown, Woodland Cedar, and Harvest Gold. The aerosol Waterproofing Stain comes in Sequoia Red, Acorn Brown, Maple Brown, and Woodland Cedar.

Thompson’s Total All-In-One Stain + Sealer is available in toner, semi-transparent, and solid options and comes in Mountain Cedar, Pacific Redwood, Canyon Brown, Golden Wheat, Hickory Brown, Sedona Red, Chestnut Brown, Atlantic Blue, Red Sandstone, Amethyst Green, Blue Peacock, Driftwood Gray, Forest Green, Iron Black, and Black Diamond.

Their line of Penetrating Decking Oil comes in Pinecone, Crimson, and Hazelnut, while their transparent and semi-transparent timber oil comes in Teak, Walnut, Cedar, Redwood, and Mahogany

Best choice
Thompson's Water Seal
Thompson's Water Seal

Applying Thompson’s water seal to your deck and other outdoor surfaces is an important step in keeping them safe from environmental damage and beautiful for years to come.

View Deal

How to Stain and Seal and Redwood Deck

How to Stain and Seal and Redwood Deck

Staining and sealing any deck can be a simple DIY project that you can tackle on a weekend if you know what to do and the sequence in which to do it. The link above provides an in-depth tutorial on staining and sealing a Redwood Deck and below we have provided the tutorials highlights.

Before you’re able to start staining, you must first consider the wood prep option that is right for you.  Some woodworkers recommend that you leave the untreated wood to “rest” for three to twelve months before staining. This gives the wood adequate time for its oils to fully settle and dry. The second option is for the wood, once installed, to dry for a week prior to staining and then proceed with the application. Both methods have their pros and cons, and the choice should ultimately come down to the climate you’re in and the type of wood available.

The first step you’ll need to take when it’s time to stain and seal your deck is to clean it up. Sweep the deck surface thoroughly, being sure to get into all the corners and crevices. Use a long, slim tool to release pebbles, sticks, leaves, and other debris from the cracks between the boards.

Next, you’ll be sanding the entire surface of the deck including the sides of each board and the end trim pieces at both ends of the deck. Use 150 or 180 grit sandpaper and sand with the grain. Once sanding is complete, you’ll want to give the deck another good sweep to remove sawdust left behind from sanding.

Finally, you’ll be able to stain. Apply the stain with a four-inch brush working one plank at a time. This ensures you do not overcoat one plank and under-coat another. Don’t forget to stain in the cracks between boards and all the trim pieces, handrail, and balusters if they are a wood grain finish.

Once the seal has dried for forty-eight hours it is safe to walk on. And after seventy-two hours you can put the patio furniture back in its place.


Applying Thompson’s water seal to your deck and other outdoor surfaces is an important step in keeping them safe from environmental damage and beautiful for years to come. Thompson’s Transparent Water Seal is an ideal product to consider when you simply require superb waterproofing capabilities. If you want a combination of waterproofing and UV protection, consider Thompson’s Semi-Transparent and Solid options.

We’d love to hear from you. Leave a comment to let us know if this article was helpful and if you have any questions about this topic.

Happy sealing!