Can You Paint Over Thompson's Water Seal?

Ossiana Tepfenhart
by Ossiana Tepfenhart
There are few products better for water sealing wood than Thompson’s Water Seal, but it’s not always clear whether or not you can paint over it. It is possible to paint over Thompson’s Water Seal, but only if you wait 45 days and follow the proper steps. The last thing that you want to do is waste a layer of paint, so let’s see how you can paint over Thompson’s Water Seal and make it stick.

If you need to have wood waterproofed, then chances are you’ve applied Thompson’s Water Seal to it. This waterproofing stain is known for being one of the best in the home improvement world when it comes to keeping your materials looking great. Of course, many of us want to make our projects look even better with a fresh coat of paint. But, is this actually doable?

You can only paint over Thompson’s Water Seal if you wait 45 days and use a primer. This only works if you paint over concrete, but paint doesn’t always stick to the Thompson’s seal well. Your paint may not look as intended because Thompson’s Water Seal has hydrophobic tendencies.

Deciding to paint over a water-repelling treatment isn’t something you should do lightly. That’s why you should read this article before you pick up a paintbrush.

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Is It Possible To Paint Over Thompson’s Water Seal?

It seems like it’s doable, though you might not want to try it. Officially, the Thompson’s website advises against painting over any of their water seals. The company notes that the hydrophobic nature of the product could potentially cause the paint to bead up or not even “catch” on the wood.

Though the official site warns against it, people have been able to paint over old Water Seal with the use of a pressure washer and a heavy coat of primer. If you choose to paint over the water seal, make sure to choose the right paint for the job. Anecdotal evidence suggests that latex-based paint doesn’t work well with this treatment.

Is It A Good Idea To Paint Over Thompson’s Water Seal?

Honestly? You really shouldn’t.

In most projects that would involve Thompson’s Water Seal, you’re dealing with a waterproofing wood stain or cement stain on a deck or patio. This means that the Water Seal might already have a stain that adds to the color of your deck or cement. Painting over it is just superfluous.

Moreover, painting a deck that’s been treated with TWS might just be too much work. The prep time is high, and the paint might not hold very well. If you want to paint the area and keep it looking bright, expect to give it touch-ups and regular repainting sessions throughout its lifespan.

What Would You Have To Do In Order To Paint Over Thompson’s Water Seal?

This all depends. Some people say that there needs to be a waiting period, while others say that you just need to remove the water sealant altogether. A good way to start this off is to take a look at how effective the Thompson’s Water Seal is at repelling water, and then go from there. If you need to prep and paint your deck area, this is what you’ll need to do.

  • Mix a solution of wood strippers and water in a large bucket. When choosing a wood stripper, look for one that works on hydrophobic materials. Mix the solution as directed on the package, and apply it to your deck.
  • Grab a power washer, and power wash the area you want to paint. Rinse away the stripper and any contents that come off with it. Let the area dry. Your deck may still have a stained appearance, but the hydrophobic material should be all but gone.
  • If you are painting over concrete, get a sandblasting kit to remove the water seal. This may be a little “extra” but it usually works.
  • Use a power sander to sand down any wooden area you want to paint. To fully remove Wet Seal, you need to sand down the area. This may take a while, but once you see the paint results, you will realize it’s totally worth it.
  • Apply a couple of coats of primer. Make sure that the primer that you pick is congruent with the paint that you choose. We suggest avoiding latex-based paints unless you’re absolutely sure that you have removed the entirety of the Thompson’s Water Seal. Let the primer cure according to the instructions on the can.
  • Do a spot test with your paint in a corner. If the spot test turns out alright, finish adding the paint to the rest of your deck.

How Can You Tell If It’s Okay To Paint Over The Water Seal?

If you didn’t seal your deck recently, you might be good with just adding primer and painting it. Most of the products from Thompson’s will stop protecting against water on four to six years. If you’re painting concrete, you usually can go for it after 45 days unless you applied Thompson’s Water Seal AdvancedClear. (You can’t paint over AdvancedClear!)

A good sign that you shouldn’t paint over your Water Seal is to see if water beads up on the surface or if it is able to remain dry. If it does, you may need to wait longer or just remove the sealant.

How Can You Tell If The Paint Isn’t Compatible With Thompson’s Water Sealant?

Removing the sealant entirely is the best way to make sure you won’t have compatibility issues. If you want to try to skip this, avoid latex-based paints, as they are known for not “taking” to any surfaces that are treated with Water Sealant. With that said, a spot test will help you determine what might work best.

Officially, there are no paints that are compatible with Thompson’s Water Sealant. That’s why we’re saying that the best thing you can do for your deck (or asphalt) is to remove any existing sealant before you paint.

Can Water Seal Be Used On Top Of Painted Surfaces?

According to Thompson’s website, the answer is a firm no. This is because the water seal may not adhere properly to the paint or may cause the paint to run.

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Related Questions

Can I use Thompson’s Water Seal indoors?

Nope. Thompson’s Water Seal is a product line that is strictly meant to be used on outdoor projects like patios, porches, and decks. Using this indoors is not a smart, nor safe choice. It doesn’t seal porous surfaces.

What happens if it starts to rain after applying Thompson’s Water Seal?

If your water seal is given enough time to dry, it will lock out the water from the rain without any issue. If you have a burst of rain shortly after it’s applied, you might notice the Water Seal coat getting cloudy. However, you shouldn’t be worried. It’ll work fine and clear up in due time.

Can you apply Thompson’s Water Seal to wet wood?

Wet wood and Water Seal don’t mix very well, but there’s good news here. It is possible to successfully apply Thompson’s Water Seal to damp wood. So, if the wood you want to seal is wet, just wait two to three hours. It should be dry enough to work with the sealant then.

How often should you seal your deck?

It can vary depending on your environment. However, if you want to have a truly spotless deck that is water-resistant, you should try to seal it once a year. Most people, though, can keep their decks looking good with a sealing session every two years.

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Ossiana Tepfenhart
Ossiana Tepfenhart

Ossiana Tepfenhart is an expert writer, focusing on interior design and general home tips. Writing is her life, and it's what she does best. Her interests include art and real estate investments.

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