This post was updated on May 9, 2022
Thompson’s WaterSeal Waterproofer Plus Clear Wood Protector is designed for all exterior wood and decking surfaces. It’s supposed to provide water repellency, prevent water damage, maintain natural wood grain, and resist mold growth. But this Thompson’s WaterSeal product has clearly not been a consumer favorite with professional deck restorers, largely because it doesn’t offer any UV protection and grays in just a few months.
If you have any experience with this product, we’d love it if you shared your Thompson’s WaterSeal reviews and photos in the comment area below.
Thompson’s WaterSeal Clear Waterproofer Ratings (Out of 10)
Appearance After Initial Stain Application: 8
This Thompson’s WaterSeal clear waterproofer did not alter the appearance of the wood. After it was fully dry, we tested its ability to repel water, and water did bead on top of the finish and did not absorb into the wood.
Preventing UV Graying at 2-Year Mark: 1
As far as we can tell, this Thompson’s WaterSeal product does not prevent UV graying at all. This is a huge disappointment, as preventing UV graying is the number one reason to stain your exterior wood and decking.
Wear/Tear and Peeling: 8
The Thompson’s WaterSeal clear waterproofer penetrates deep into the wood. There was no peeling or wearing. We would have given it a 10 if the product still repelled water, but at the 2-year mark, it did not.
Cost per Square Foot: 9
Thompson’s WaterSeal Waterproofer Plus Clear Wood Protector is a very inexpensive product, and its coverage is exceptional. Unfortunately, the saying “you get what you pay for” applies here, as this Thompson’s WaterSeal product offers no UV protection whatsoever.
Preventing Mold/Mildew/Algae: 2
After 2 years, the entire deck was covered in black mold. It seems that the oils used in Thompson’s WaterSeal Waterproofer Plus Clear Wood Protector feed and promote the growth of mold spores.
Ease of Application: 8
Since this is a clear product, it applies extremely easily without the need to back wipe. Just apply it with a pump sprayer or stain pad. This finish does not show overlap marks.
Color Shifting (Darkening) After 2 Years: 7
This product darkens in color because there was a good amount of mold growing in the finish.
Difficulty of Reapplication: 6
A heavy cleaning would be needed to remove all of the graying and mold from the surface.
Overall Score: 6.125
Overall, Thompson’s WaterSeal Waterproofer Plus Clear Wood Protector is a clear disappointment. Any finish that offers zero ability to prevent UV graying should not be considered for your deck or exterior wood.
Photos of Thompson’s WaterSeal Clear Waterproofer’s Effects
Product Information
- Cost: $34.99 per gallon
- Stain Type: Clear water repellent
- Available Colors: Clear
- Application Temperature: 45-95 degrees F
- Coats Required: 1
- Coverage per Gallon: 200-300 square feet
- Application Tools: Sprayer, pad, brush, roller
- Dry Time: 48 hours
- Cleanup: Mineral spirits
- VOC Compliance: 250 compliant in all states
- More Info: Product Data
- Manufacturer: Thompson’s
About Our Test Deck
- Deck Wood Type: Teak
- Deck Square Footage: 400 square feet
- UV Exposure: Full sun
- How Many Years Tested: 2 years
- Stain Color Used: Clear
All products tested and results are from our experience. We offer no guarantee of similar results. Take into consideration that results may differ due to different wood types, exposure to UV radiation, and natural weathering.
Thompson’s WaterSeal Clear Waterproofer FAQs
Is Thompson’s WaterSeal Any Good?
Our experience with Thompson’s WaterSeal Waterproofer Plus Clear Wood Protector was disappointing overall, and we would not recommend this product. Its inability to prevent UV graying is too harmful to your deck’s wood.
What’s Better Than Thompson’s WaterSeal Waterproofer?
Restore-A-Deck Semi-transparent Stain and Armstrong-Clark Transparent Stain are two excellent alternatives to Thompson’s WaterSeal Waterproofer Plus Clear Wood Protector.
How Long Does Thompson’s WaterSeal Last?
Thompson’s WaterSeal Waterproofer Plus Clear Wood Protector claims to last for up to 4 years when applied correctly. In our experience, it held up well but no longer repelled water after 6-12 months.
Is Thompson’s WaterSeal Waterproof?
Thompson’s WaterSeal Waterproofer Plus Clear Wood Protector is made to waterproof exterior wood.
Can You Use Too Much Thompson’s WaterSeal?
Yes: Applying too much Thompson’s WaterSeal clear waterproofer will significantly increase the amount of time it takes to dry, and it may not dry properly at all.
Does Thompson WaterSeal Protect Wood?
Thompson’s WaterSeal Waterproofer Plus Clear Wood Protector is intended to protect wood, as the name would indicate, but our testing produced dismal results. It does a very poor job of preventing black mold and UV graying, two things that are very harmful to the wood.
Is Thompson’s WaterSeal Water- or Oil-Based?
Thompson’s WaterSeal Waterproofer Plus Clear Wood Protector is an oil-based product.
How Do You Use Thompson’s WaterSeal Waterproofer Plus Clear Wood Protector?
This product is easy to apply with either a stain pad or a pump sprayer.
Does Thompson’s WaterSeal Contain Silicone?
No, this Thompson’s WaterSeal product does not contain silicone.
Does Thompson’s WaterSeal Come in Different Colors?
This particular product is clear, but they also make Thompson’s WaterSeal Waterproofer products that include Thompson’s stain in different colors.
How Many Coats of Thompson’s WaterSeal Do I Need?
In most cases, you will only require one coat.
Can Thompson’s WaterSeal Be Used on Stained Wood?
No, Thompson’s WaterSeal Waterproofer Plus Clear Wood Protector cannot be applied over stained wood, regardless of whether the stain was oil- or water-based.
Does Thompson’s WaterSeal Darken Wood?
Our review of Thompson’s WaterSeal Waterproofer Plus Clear Wood Protector found that it did darken wood over time due to the large amount of black mold that grew in the finish.
How Long Does Thompson’s WaterSeal Take to Dry?
The Thompson’s WaterSeal dry time is approximately 4-24 hours before it is considered safe to walk on.
At What Temperature Can You Apply Thompson’s WaterSeal?
The application temperature for Thompson’s WaterSeal products is between 45°F and 95°F.
Deck Stain Help & Questions
Stain Reviews & Comparisons

As an article and comment contributor to the site, Scott has been around the pressure washing industry since attending college. In 1993 he started his first company called Oakland Pressure Wash specializing in exterior pressure washing and deck staining. That company evolved into OPW L.L.C. shortly thereafter concentrating more on exterior wood and deck restoration. Scott and his Deck Cleaning Michigan company have restored over 10,000 decks in the Metro Detroit area since the early years. He has become an authority in the deck restoration industry and has contributed to numerous wood restoration forums and informative sites.
All the products he suggests through this site are sold through online sites and in retail stores, allowing the consumer to choose their own means of purchase. Scott’s eCommerce sites do sell many top brands he endorses and if you appreciate any of the help he has offered then feel free to purchase from one of them.
Don’t waste your money on this product. We prepared my large deck. Applied the Thompson water seal transparent on the deck in May of last yr. I spent alot of money on this product. Now that it is spring the stain is almost off, now need to rent a sander to get the rest of it off. This product is awful does not even seem to soak into the wood. I am so glad that I didn’t do my front deck with this product.
Waited 1&1/2 years to treat new deck. Did all prep work applied in August come spring deck is peal and looks terrible . Can not get through on Thompsons phone line or email. Not happy
We didn’t like how red (almost pinkish) after applying the Thompson’ seal and stain in cedar to our new fencing. We did not over appy and followed directions. Thought it might tone down after a day, but it’s still hard to look at. So now we need to spend more money to find some other product to redo the whole fence to get a more true cedar look. Really disappointed!!
don’t confuse Thompson’s water seal with Thompson’s water seal waterproofer plus. the water proofer plus is an excellent product and yes with uv protection. it’s oil based and deeply penetrates into the wood. doesn’t sit on the surface like a stain. there is nothing to peel or wear .I just clean and reapply every two years and deck looks great
I’m water pooling a shade structure over a koi pond How long does it need to cure so it for it to be safe if it rains so it doesn’t hurt the fish
A few days should be okay.
Will applying Thompson’s clear water seal to rough red cedar affect it’s insect repellant qualities?
No, it should not.
I think I used to much it’s been 4 days and it won’t dry what can I do?
You will have to remove all and start over. How to remove, depends on the condition, stain brand, and stain type that was used? Pics would help. You can post them here.
Want to know since Tho
psons is no good for decks whether to use paint or is there any preservative good! It takes a lot of time to do things right and since we have been dealing with CHINA, I lost all my respect! Everything we get is from China and yes all is TRASH!
I have interior wood Latvia’s that look dry! What do you recommend?
The products we review are for exterior use only.
I am doing a small outdoor project using 1/2″ plywood and would like to know the best sealer to use on the surface and sides. The plywood will be exposed year round. The plywood does have some small knots on both sides and some small voids on the edges. I need to do both sides. I guess what I am asking is, what do I do to make my project water proof? Since the rest of the project is natural unstained cedar it would be nice to have the plywood be cedar color or a brown color.
I was going to use Thompson Water Sealer but after reading this article that is not going to happen so i need something different but still economical.
Comments / suggestions would be most welcomed.
Thank you
Randy Marshall
Calgary, Alberta
Canada
Try TWP 200 Series or Armstrong Clark stains.
It used to be one of the best products on the market until the EPA made them change the their formula. It is now fair at the very best. I would not use it or recommend it to anyone.
Water Based Nightmare!!
Seems that not too many have good results with this product. I have used it for the last 9 years on my deck and redo every 3 years. The deck does get dirty from the crap from the trees and the dirt in the air. I pressure wash the seams between boards and use bleach to clean the boards before re-applying Thompson’s Clear Sealer. BUT – since everything is now ‘safe for the environment’ I can only get the water based version of this product. I did about 100 sq feet with the oil based stuff I had left over from last sealing and the rest (500sq feet) with the new water based crap. And it is very crappy looking compared to the oil based product.
I guess I will live with this until midsummer and hope that it all fades. Otherwise I will go get a sander and refinish the entire surface. Maybe I can still get the oil based product in the states..
We were told to wait at least a year before staining our new deck with Thompson’s Water Seal and Stain. We stained last fall. This is what it looks like less than 7 months later. We applied a thin coat of stain to dry deck boards. Not very happy with the results and not real sure how we can fix this horrible mess. Suggestions appreciated.
Remove is all. Strip with the Restore A Deck Stripper and both additives: https://www.deckstainhelp.com/restore-a-deck-stain-stripper-booster-thickening-gel-review/
The RAD Brightener after.
Used this on several items. Looks awful after one year.
Why won’t this dry? I used it on a bench which must dry for people to sit on but now I have to sand it back down so I can use something else on it. Not happy at all with this product!!!!!! I got it at Lowes and I am not sure if it is not any good or not but it looks milky and it should be clear. I will never buy this again.
It is a very poor product. Many issues with drying and performance.
Put the sealer on my deck used cedar and it’s coming off within a year and a half. What went wrong?
It is a very poor product. Does not work well and does not last. So what went wrong was not your fault, but their’s for selling it in the first place.
So what sealer/stain is quality and do I need to sand the deck. I need to know what steps to take to redo my deck. Thank you so much for your input.
Strip and brighen to remove the Thompsons fully. Stain with TWP Stains or Restore A Deck Stains.
Thank you!
Spent several days cleaning my 300 sq ft deck with pressure washer. Let the deck dry for about a week (no rain). Bought a gallon of Thompson’s clear and sprayed on with a pump sprayer. The Thompson’s gunked up about an hour after it was applied. Hour or two later there was a chalked substance on the surface of the wood. Used a steel brush to remove it. Wood surface has yet to dry completely after 3 days and is so slick, slippery you can hardly walk on it. The wood is now very dark as if it had been a fire. Thompson’s solution is to take sealer back for a refund. Junk.. Anyone know what to do next?
Post some pictures for help.
The surface is so slick that you can’t walk on it. Also, when I go out to cook on the deck, I have to wear booties to prevent tracking up my hardwood and rugs inside.
You will need to remove it. Strip and brighten with Restore A Deck Stripper and Brightener Kits.
Thank you Einstein! Your product is the worst!
I think you are missing the point of who we are. We are not Thompsons or make it but an independent review site that agrees that Thompson is poor. If you do not want our help with trying to fix it, then why ask and then be rude about it?
I thought you were Thompson’s.. I truly apologize. Thanks for your suggestion.
No issues, their products are very poor. Hope it all works out for you.
we applied the product a week ago and it will not dry, very sticky, stepping on it sticks to the shoes and we ended up with the sticky shoe prints through my dinning room floor. We cannot get it off my floor. I’ve since returned the product got my money back. But now i have damage to my floors. I am very very disappointed in it. I will not recommend this product. In order to get my deck back I am going to have to buy paint thinner to remove it they the store manager said. And it will take a lot I imagine. Grrr I am not a happy camper with this product.
Was very disappointed with “Thompson’s WaterSeal Waterproofer Plus Clear Wood Protector” This was the “Clear” version of the product, with no Tint or Stain.
I have a video of the application but was limited to a snapshot of the video, due to upload size limitations. Even from the attached snapshot, you can see the product turned my wood much darker than the original color. Definitely, NOT CLEAR.
I power washed the wood over a week ago, and following the direction on the can, made sure the wood was dry, the can was well shaken, and it was above 50 degrees. The attached picture was a second attempt, done with a hand roller as shown in the Thompson’s site video applying the product and using a minimal amount of the product. This is 36 hours after I applied the product, and I do not see it lightening up any, to match my original wood color.
As you can “clearly” see (sorry for the pun) the wood is a much darker color than my original wood color. I also did another attempt and used a small sprayer to apply the product and ended up with the same outcome.
If you need to be a professional painter to use this product, they shouldn’t sell it to the layperson.
Is 2 coats of Thompson’s WaterSealer/Advanced on a decks bettwr than I coat?
No. Zero is better than any. Choose a better product.
We had a New 14′ x 12′ deck built in November 2020. We sealed it in March 2021 with Thompson All in One Stain and Sealer Honey Gold. It is now Going into July 2021 and i have black streaks dots and spots all over where the sun hits. Tried to use Valspar Deck cleaner today with no such luck on the black coming off, or the streaks. It now has a white bleach look. I’m lost at what to do next!
You will probably have to remove it all by stripping and or sanding to fix. Brighener after.
Stain with a higher quality stain after:
https://www.deckstainhelp.com/the-5-best-deck-stain-reviews-and-ratings/
Thank You. I kind of figured that is what i was going to have to do. I have been searching for the best stain, cleaner and brightener to use. No more Being Cheap!
Looked good first summer. Winter and snow came and in the spring at least 50% was gone. Two years 90% gone. Very dissatisfied.
Can you reapply the clear watersealant a year later with out removing the previous application?
No, you have to prep.
Why won’t it work with a sprayer. I tried 2 different sprayers and all the different tips. It seems to be to thick. What do I do to make sprayer work???
You cannot spray it with a pump sprayer if too thick. Only an airless sprayer.
Very dissatisfied with Thompsons product. Peeling and white color when wet. I now have to remove what is left on porch before re staining with oil base stain. because Thompsons did not last for two years my porch became weather damaged and the color is uneven. Again, VERY dissatisfied😠
Applied water seal last summer, it began peeling and flaking over the winter, now this spring I will have to redo the whole deck. I’ll find another product and hope for better results. I will not recommend this product.
I’m in the same boat. Very disappointing.
I’ve used this product for several years. It looks good after applying but doesn’t last. I apply every spring. Starts flaking in winter and looks horrible by spring. I would change product but I would have to restain the vertical slats to match the planks. I reapply every spring to the horizontal planks and touch up the rest of the deck. It would be best to avoid this product from the start.
Mine also started flaking about 3 weeks later. I worked so hard on staying my deck and I am very disappointed.
I used this last year. Completely pressure washed the whole deck and waited a week to be sure it was dried before I applied the stain. Went on good, looked good. Dried quickly. It rained about a week later and noticed it repelled good, but it left water rings. Got thru the winter and half of the stain has peeled up everywhere by spring. I couldn’t believe it. Will not use this product again. Deck paint would have held up better. Very disappointed.
Hi
I want to seal a pew for outdoor use.
Do I need to sand the pew first? It’s an old church pew, already stained.
You cannot apply a sealer over stained wood. You would have to fully remove the old coatings first and then use an outside stain.
Is this review of the Thompsons water-base or oil-base sealer? I have an oil-based thompsons clear that now I’m worried about using on my new fence.
The clear will be useless on your fence when it comes to UV protection. It will gray in months. Review is for the oil version but the water based is just as bad.
Last spring I sanded my deck to bare wood and fully cleaned and dried it before applying Thompson’s WaterSeal Semi-Transparent. No issues with stickiness, looked great for awhile, but it’s now ten months later and half of it has peeled off. Looks awful, no protection. Guess I get to do it all again, with a different brand this time. 🙁
I sealed my deck about 5 days ago with Thompsons clear. I dont see how your sprayers didn’t work. Mine worked fine. It was all dry in about 2 days like the can said. No stickiness what so ever. I think the only thing I can think of is people are way oversmdoing the amount if its not dry after weeks or using. The only concern I have is that little water rings are left behind where the water was sitting after my sprinklers went off. I hope after a rain the whole deck doesn’t look like that. I’ve used this product before with no problem. Did the ingredients change?
I stained my new deck 3 years ago with Thompsons water sealer and I loved it. It looked great and no issues with being sticky. One month ago I had to stain my deck so I bought the same brand and color of water sealer. I did all the prep just like the bottle said, and I let the deck dry for 4 days. This time after using Thompson’s water sealer I am very disappointed. The deck is sticky, so sticky my shoes stuck to the stairs and i fell down.
I really injured my leg and back. I don’t let anyone out on my deck. I need to hire someone to remove Thompson’s water sealer and apply a different brand. After calling the company they said we can refund your money as long as you have your bill. I got my money back but now I have a bigger problem and it’s going to cost me a lot because I am unable to do the work after injuring myself. STAY FAR AWAY FROM THIS PRODUCT.
I WILL NEVER EVER BUY THIS PRODUCT AGAIN…
Can you paint over it
No, it will repel the stain or paint and it will peel.
2 WEEKS AND STILL NOT DRY! We had our porch redone by a company and they used this product. We were told to not walk on the porch and use our back door for 2 days. We’re now going on week 2 of this issue. The porch remains sticky. What a nightmare.
Can u apply it 2 days after applying Cabot stain on your deck?
No, you can never apply a sealer over a deck stain.
Sikkens offers clear coat for over their stains[cetol maintenence]
Yes, and it will peel.
Does Thompson waterproof honey stain peel?
Probably will.
How long does it take to dry? Its been 24 hours and is still wet and oily.
It should dry soon, if not, you will have to remove and start over with a better brand.
Try wiping the excess off Mary, the wood will only absorb so much and the rest will just sit there.
Product is crap don’t waste your time or money! Wish I had of read the reviews first!!
I am only giving them a one star review because I can’t post with a no star ! we have always used their water sealer and when I reached out to customer service for a problem no one returned my emails even though it says they will get back to you in one business day!!! And I couldn’t get through on the phone so a product is only good if a company stands behind it very disappointed . Will not buy it again.
Looks lovely when dry but don’t use this product unless you want to be mopping puddles up off your deck every day. Water just sits on the deck now and creates a slipping hazard
I put Thompson water sealer on my deck 10’x42′ it repelled water for the first year and everytime it rained you could see the oil coming to the surface and it cupped up almost all of the 5/4 deck boards and most of them began to squeak had 3 screws in each joist , had to screw 2 more screws in to stop squeaks graying and molding after 1st year this stuff is crap will never use again
Does Thompson’s water seal and the others need UV light in order to cure properly?
Almost all stains or sealers need the sun to help it cure.
This product ran down wooden columns colllecting on concrete patio floor. Right now it is still not completely dry. What is the best way to get it off the concrete?
Honestly, I do not think you can as it is designed to penetrate deep.
Daughter and son on law in NOLA, used a Thompsons water sealant in April, in July their deck is still super sticky.
Sealed my whole deck , low and behold we had a thunderstorm and it rained 3 hours later .. will I have to reapply?
Hard to say. Probably okay.
I sealed my deck , but as my misfortune we had a thunderstorm and it rained .. it only had 3 hours drying time . Will I have to reapply ?
Last summer I applied Thompson waterseal in the cedar tone to a cedar deck. This spring it has mostly flaked off or is flaking. Would not recommend this product
Will this particular product leave a sticky residue
Maybe as it has issues drying.
No it doesn’t. Just make sure it’s clean and dry and use a staining pad to apply evenly. I’ve only used Thompson’s water seal and my fence looks as good now as it did 16 yrs ago. I touch up a section every year for my own personal preference. Dries quickly.
My deck, same.
So glad you had good luck with it. Maybe it’s OK on a fence but definitely not on a deck even though we had no rain it didn’t dry and now when you walk in onto the hardwood floors it leaves foot prints !!So frustrating as I have tried to contact a company multiple times and nobody returned your emails
This is what’s happening to us. It’s dry because water beads up on the deck, but when we walk on the deck some kind of residue is on our shoes/socks/feet and it gets on our hardwood. We may nave to have deck shoes only allowed for the deck…
Ugh so much work for nothing 😣 even my dogs leave foot prints! I am going to try dawn dish soap as a degreaser fingers crossed
I have used this product many times and it has never left a sticky residue.
Just used Thompson’s Waterseal Waterproof Solid Stain in Acorn color on my deck. I completely sanded it down to bare wood (pain in the ass!) and applied the stain EXACTLY as directed. Dried in about two hours, looked great – then, today, 4 days after I stained the deck, it rained. It did seal the wood, the water pooled on top of the wood but, as it evaporated it left milky white patches and spots all over the deck – like putting a wet glass down on a piece of wood furniture will do.
I’m completely disgusted with the amount of time, effort,and money I put into this and got to enjoy it for a whole 3 days! Is there a way to prevent this from happening? What a nightmare! I’ll never use Thompson’s products ever again.
Thompsons Water Seal multi-surface waterproofer:
Twenty months ago I cleaned our screened redwood porch floor as well as our treated outside deck with Jomax deck cleaner as I had done 18 months prior, and so on ad nauseam for the past 17 yrs. and applied Thompsons Water Sealer according to the directions on the cans. The porch floor is still tacky. The deck less so but not ‘sealed feeling’ as in previous years. The only variation I can imagine is the higher humidity during the application. In the past, the sealer has worked as advertised and loses effectiveness (depending on weather) between 12-10 months. I was willing to repeat the
process in such a short time because it offered an opportunity to keep a close eye on the aging materials and construction.
Now I find myself with another costly (both time and money) step in order to seal my outside non-painted wood. It seems the only way to get rid of the tackiness is with a lacquer thinner wipe after the cleaning. I’m hesitant to apply TWS ever again. Unfortunately, I still have enough product safely stored to do half the project. What a waste.
I used Thompson weatherseal with a tint last summer, this spring after the snow left it had already peeled and looks horrible! It in most places is not repealing any water. What can I do now? Can I restrain with a better product?? I was told that once you use Thompson’s you can never use anything else because the silicone goes down in the boards and then a stain can’t properly penetrate? I already pressured washed and then stripped off the remaining , is it true now that I can’t stain? I don’t want to be doing this every year.
Sand or strip it off to remove it fully. You can use a different stain after. Try one of these: https://www.deckstainhelp.com/the-5-best-deck-stain-reviews-and-ratings/
I have replaced the floor of my 21 year old deck with composite planks. The original joists and supporting posts are pressure treated lumber, in good condition presently but 21 years old. What can I do to help preserve the wood from rot and protect my investment?
There is no need to apply anything to the joists or posts under the deck nor would it help.
Have a deck 30 plus years old none pressure treated . Each spring and fall I pressure wash and reapply it has been an awesome product for me the proof is in the deck. Our winters here ( PEI Canada) are long and harsh but the product has proven up to the challenge.
Product states it can be applied by spraying. No matter how much I mixed or shook it, it would not spray in my (Decks and More) sprayer. All the parameters of temperature and thorough mixing were observed and applied. I ended up having to brush it on which make a 5 hour job take 16 hours. Wow! What a disappointment. I’ve used this brand and other deck sealer brands in the past and applied all of them with a sprayer with satisfactory results. However, this clear sealer this time would not spray no matter what I tried. Also, my sprayed is always cleaned and properly maintained. This wasn’t the issue. Probably won,t buy Thompson,s water seal again. Instructions for application are misleading.
I completely agree with you. I had to apply witth a roller. Have used many times before but will not use again. Too thick to be applied by spayer. I even bought a new sprayer just for this application.
Same problem with Deckers and More sprayers