If you’re like me, then you love your deck. You’d take it with you if the zombie apocalypse hit and forced everyone to move underground. It’s a great place for entertaining guests or just enjoying a cup of coffee in the morning.

But what do you do when it starts looking shabby? Can you use Thompson water seal over stained wood deck?

That’s where this post comes in handy! I’ll tell you how to use Thompson Water Seal over stained wood so that your deck looks as good as new again.

Ready to get started? Let’s go;

Can You Use Thompson Water Seal Over Stained Wood?  

Yes, you can put Thompson water sealer over stained wood whether the stain is water or oil-based. But surface preparation is key. If the stain has completely dried and cured it’s fine to apply sealer, but if there is still some moisture, applying the water seal over the stain might cause problems.

How to Use Thompson Water Seal Stain Over Stained Wood 

You can apply the sealer with a paint roller or brush, but a pump-up sprayer is the best option. The sprayer allows even coverage to any exterior wood surface, whether with railings or decking boards. 

What you will need 

  • Thompson’s water seal
  • Pup-up sprayer for applying the sealer
  • Painter’s tape  
  • Microfiber cloth or rag for cleaning the surface
  • Water  
  • Plastic sheeting or drop cloth 
  • Sandpaper (fine grit)
  • Safety goggles 
  • Synthetic scrub brush 
  • Heavy-duty plastic gloves 

Steps to put thompson’s water seal over stain

First, ensure you have all the supplies you’ll need to complete the project. 

Step 1: Prepare your workspace

While using a pump-up sprayer for sealing your deck wood will ensure some precision, you still need to get movable objects out of the way. If you are working on your deck, start by removing garden plants and furniture. 

You may also want to wear protective goggles and rubber gloves before you start handling the sealer. 

Step 2: Clean the stained wood 

How you clean the stained wood will depend on how dirty or worn it is. If you’re working on freshly stained wood, there are chances you already cleaned it before applying the stain. So, a thorough cleaning won’t be necessary.

In this case, all you have to do is rub it back and forth with a damp microfiber cloth or lint-free rag. Wet the cloth with clean water and wring it to remove the excess water before cleaning the surface. 

Let the clean, stained wood surface dry before proceeding to the next step.  

1. How to clean an old stained wood 

If the wood has had the deck stain on it for a while, it may have accumulated dirt and grime. It’s essential to clean away these things before waterproofing your deck. 

In this case, you will need a suitable deck cleaner to remove the accumulated dirt, molds, and mildew that might be on the stained surface. You could go for Thompson’s water sealer deck cleaner or any wood cleaner of your choice. 

Spray or apply the wood cleaner following the manufacturer’s instructions, and scrub lightly with a sponge, microfiber cloth, or long-handle brush if you are working on a deck.

Then rinse the boards thoroughly with a garden hose to remove the cleaning solution and dirt. 

Once done, leave the surface to dry overnight.  

2. How to clean an oil-based stained wood surface   

If the wood has an oil stain on it, you will want to remove it. Ensure the stain is thoroughly dry before sealing it with Thompson water-based topcoat. 

For a freshly applied deck stain, follow the manufacturer’s instructions regarding the drying time. This could be anywhere from 12 to 18 hours of waiting time or longer. 

Once the oil stain is completely dry, wipe the entire surface lightly with a clean, lint-free cloth dampened with a solution of denatured alcohol and water. 

Prepare the wiping solution by mixing equal parts of denatured alcohol and water. This wiping exercise is crucial. It helps remove any oils and mineral spirits on the stained wood surface that might hinder proper sealer adhesion.

Once you finish wiping out the oils and mineral spirits, let the wood dry and go over it with fine-grit sandpaper. 

You don’t have to sand too hard; just scuff it up to improve adhesion. 

Step 3: Protect the adjacent lawn and objects 

Cover anything you can’t move out of the way with plastic sheeting or drop cloth to avoid getting the sealer where you don’t want it. This can include furniture or garden plants. 

And, if there’s an area of the wood you don’t want to get the sealer, such as the deck siding, apply painter’s tape over them for coverage. 

Step 4: Prepare the sealer 

Any Thompson product will usually deliver the desired results if you use it correctly. 

In this case, you are likely to use the clear-colored Thompson’s Water Seal because the wood already has a deck stain on it.  

To prepare the sealer, shake it well in its original container, then pour it into your pump-up sprayer’s canister. Close the canister and adjust the pressure by following the manufacturer’s instructions on the label. 

In any case, you will need to pump the handle to pressurize your sprayer if you are using a garden sprayer. The idea is to pump until you feel resistance.  

Step 5: Apply Thompson’s water seal on stained wood

Ensure you have your goggles on for your eyes’ safety and gloves to cover your hands. Then spray the product all over the wood or deck if you are sealing the deck. 

The objective is to cover every inch with a thin, even coat. 

You may cover about two square feet section and go over it with a paint roller if you are aiming for perfection. The roller will soak up any puddles that may remain from spraying. 

Notice that rolling after spraying is usually unnecessary. But if you choose to go that direction, spray small sections and go over them with a paint roller until you cover the entire wood surface.   

Step 6: Allow Thompsons water sealant to dry thoroughly 

After applying Thompson sealant, let the wood dry for at least 24 hours before replacing furniture or putting it back to use.  

The drying time may take longer if the weather is particularly cold, so always consider the weather when deciding how much drying time to allow your sealed wood. If your Thompson water seal does not dry as expected, check out our guide for solutions.

Can You put Water-Based Sealer Over Oil-Based Stain?

Yes, you can use a water-based sealer such as Thompson’s Water Seal over an oil-based stain as long as you prepare the surface accordingly. Start by allowing the wood to dry thoroughly, then wipe it down with a clean, lint-free cloth dampened with a mixture of denatured alcohol and water. 

How to Apply Water-Based Sealer on an oil-based deck stain

If you are going to seal an oil stain with a water-based top coat, ensure you prepare the surface correctly to improve adhesion and get the results you desire. 

Tips for applying a water-based sealer over oil stains

This section provides you with tips to help you get the job right

  • Always ensure the deck stain is thoroughly dry before using a water-based sealer over it.
  • Always wipe down the stained wood surface with a clean, lint-free cloth dampened with a mixture of denatured alcohol and water before applying the sealer over deck stains.  
  • Always scuff sand the surface with fine-grit sandpaper to improve adhesion before applying the water-based sealer.
  • Use a pump-up sprayer to apply the water-based sealer for even coverage.  

How to Apply Thompson’s Water Seal with a Paint Roller

While using a sprayer is the recommended way to apply Thompson water sealer, it does no harm to know how to apply the product using a paint roller. 

The procedure to follow

If you opt for a roller, start by cleaning the wood or deck the same way you would when using a pump-up sprayer. You can use liquid dish soap and water solution for the cleaning.

For a newly stained deck, consider cleaning it with a lint-free cloth or sponge. However, you may want to scrub the wood with a soft-bristled brush if it has accumulated dirt. Rinse it and let it dry. 

Next, pour the Thompson Water seal into a roller tray, dip the roller into the sealer to cover it all around, and use it to coat your stained wood.  

Be sure to coat in the direction of the wood grain to ensure uniform, even coverage. Consider starting from the middle and moving back and forth from one end to the other, keeping the pressure even throughout. 

How to Apply Thompson’s Water Seal with a Paint Pad

A paint pad is another viable way to coat your wood with a Thompson water seal.

The procedure to follow

If you prefer a paint pad to a sprayer, start by pouring the sealer coat directly onto the wood deck in small amounts and spreading it out, and see how it highlights the natural wood grain. Alternatively, apply the product by dipping your paint pad directly into the Thompson’s seal container to soak it.

Gently rub the soaked pad on the classic deck stain to clear coat the wood—along the grain.

Read also:

Best sealer for redwood deck.

Best sealer for burnt wood.

How Many Coats of Thompson Water Seal do I Need?

A single coat of Thompson’s water sealer is typically enough for both solid and semi-transparent stain color application. However, you can always add a second coat after the first coat has had at least 2 hours of drying time if you want a more solid stain color.  

Can You Use a Pump Sprayer to Apply Thompson Water Seal?

Yes, you can use a pump sprayer to apply the Thompson water sealer. But the manufacturer recommends using a plastic sprayer with a brass wand for the application. Once you complete the project, you should run mineral spirit and water through the sprayer to clean it. 

How Long Does Thompson Water Seal Take to Cure?

Under normal temperature and humidity conditions, Thompson’s water seal will dry to the touch approximately 2 hours after application. However, you should allow it up to 24 hours of drying time or longer if the weather, texture, and surface type do not support quick drying. 

How Often Should I Apply Thompson’s Water Seal?

Consider reapplying Thompson WaterSeal Waterproofing Stains every one to three years. The chosen finishing product, weather conditions, deck use, and exposure to sunlight will determine how soon you must reapply the deck sealer.  

Usually, you will only need a single application to sufficiently cover wood pores and wood fibers when using a Thompson product. The single application usually covers the wood pores adequately, making the wood waterproof.  

Tips for Using Thompson Water Seal Over Stained Wood 

While Thompson water seal products are DIY-friendly and hassle-free to apply, knowing a few best practices can go a long way in improving your results. Here are some tips to help you achieve better results and address common queries like “Do I need to seal stained wood?”

  • Target your Thompson’s deck stain application when the ambient temperature is within 50 to 95 degrees Fahrenheit range for application and drying.
  • Consider applying a clear sealer when the ambient temperature is within 50 degrees Fahrenheit range. 
  • Always check the weather forecast and plan your work when no rain is forecast for at least two days following the application.
  • Consider applying your Thompson’s water seal on a day when the weather is still for the best results.
  • Always allow your deck to dry completely before applying the Thompson water seal. Working with damp wood can lead to longer drying times.

Recommended read: Best way to seal particle board.

Is thompson’s water seal oil-based?

No, Thompson’s WaterSeal Stain is a water-based product that goes on the surface instead of penetrating into porous or natural surface. The effects are limited to the coating you put on and offer waterproof protection. Even better, they also resist mildew and protect the wood from UV rays damage.

Check out this guide on the best farm table stain for expert recommendations and tips on achieving the perfect finish.


Can you put oil-based sealer over water based sealer

Yes, you can put oil-based sealer over water based sealer. But but water based sealer must be completely dry. If the water-based sealant wasn’t completed driy before applying an oil-based sealant, the top finish might peel or crack.

Can you put an oil-based sealer over a water-based stain?

Yes! You can apply an oil-based sealer over a water-based finish, but the underlying coat must be dry before coating over it. For instance, to coat over water-based stain with an oil-based sealer or paint, allow the water-based sub-coat to dry for a minimum of 24 hours before applying the oil-based topcoat.

Can you use water based stain over oil based stain

Generally, a water-based stain such as acrylic latex stain can work over an oil-based stain. The previously oil-stained substrate must, however, be clean and completely dry for the topcoat to adhere properly. 

Can you mix stain with water sealer?

Yes, you can mix a stain and water sealer to get a tinted stain-sealer mixture to use on bare wood.  Ensure you add one product to the other at intervals and mix as you go until you achieve the desired uniform color. You can then use a roller or brush to apply the product on bare wood.

Is it possible to use water-based finish over oil-based stain?

Yes! You can put a water-based topcoat over an oil-based stain, but ensure the underlying stained substrate is completely dry before application. Also, wipe the stained surface with a clean, lint-free cloth dampened with water and denatured alcohol solution to remove the oils and mineral spirits on the wood to improve adhesion. 

What is the best finish over an oil-based stain?

The best finish over oil-based stain is polyurethane. To use a water-based poly, consider applying a barrier coat of dewaxed shellac before the polyurethane topcoat to seal the oil-based stain. (Here’s our article on shellac versus polyurethane that will help you understand each option in greater detail.) Let the thinned shellac dry, then light scuff-sand it to give the poly an excellent surface to grip.

Read: What is the best sealer for outdoor wood furniture?

Can you use Thompson water seal over stained rifle gun stock wood?

Yes, you can use Thompson WaterSeal over stained rifle gun stock wood. Ensure the stain is fully dry and cured before applying. Moisture in the stain can cause issues. For finishes for gun stocks, follow specific firearm or wood finishing product recommendations for best results.

Can you use Thompson water seal on pressure-treated wood?

Yes, you can use Thompsons Water Seal on pressure-treated wood. You just need to be sure the treated wood is dry enough to take the sealer. Some, such as Thompson’s WaterSeal Waterproofing Wood Protector, advocate waiting 30 days before applying on new pressure-treated wood. Other sealers, like Thompson’s WaterSeal Waterproofing Stain, may be used on new pressure-treated timber right away.

Read also: Method of applying outdoor paint sealer for wood.

Thompsons Water Seal over Stain

So, can you put Thompson water seal over stained wood?

Combining Thompson water seal with exterior stain can give your wood a rich color and UV protection, in addition to protection from water and moisture damage. 

If you choose to use a Thompson product over stained wood, you can always use this article to guide you through the process.

Also, read our article “Thompson water seal vs Olympic Waterguard” for a detailed comparison of these two popular wood sealers to make an informed choice for your project.

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