Is Thompson's Water Seal Any Good for Wood, Brick and Concrete?
Worth it, with a yearly recoat
Why deck wood turns gray no matter what you do
Run your hand across a deck board in July and you can feel it before you see it, that dry, papery graying that means the wood has given up its oils to the sun and rain. Is Thompson's Water Seal any good at stopping that, or just another can promising protection it can't keep. The board doesn't lie, even when the packaging does.
How Thompson's WaterSeal actually seals wood, brick and concrete
Here's what's actually happening under the surface, because it matters more than the label copy. This is a penetrating sealer, not a film like paint or polyurethane, so it doesn't sit on top of the wood, it soaks into the grain and cures inside the fibers, closing the pores that pull water in. That's why rain beads and rolls off instead of sinking in and swelling the boards, and it's also why the wood keeps its natural color and texture instead of looking shrink-wrapped. Because there's no pigment, none of the existing graying gets covered up, only what happens next gets slowed down. The same mechanism explains why the can works on brick, concrete and masonry as well as wood: any porous surface with capillary pores that pull in moisture responds the same way once those pores are sealed, which is why this reads more like a waterproofer than a wood stain. And because it's a water based formula, cleanup is soap and water rather than mineral spirits, worth knowing before you start, not after your brush has gone stiff in the sun.
So you're not buying a new finish for the deck, you're buying a barrier you can't see, which is exactly the point since the wood is supposed to look untouched. The trade is honest: no color change, no sheen, just wood and masonry that shed water instead of drinking it.
Who Thompson's WaterSeal is for, and who should skip it
Worth it if
- you want to protect wood without changing its natural color
- you need one product that works on wood, brick or concrete
- you don't mind reapplying on a roughly yearly cycle
- budget matters more than a premium multi-year system
Skip it if
- you want a stain that changes or deepens the wood tone
- you want strong built-in UV fade protection
- you're not willing to recoat every year or so
Not for anyone wanting a color change or a multi-year finish without recoating.
Is Thompson's Water Seal worth it, the verdict
If you want your deck, fence or brick path to keep looking like itself while shedding water, this earns its spot in the shed. If you want a one-and-done fix that lasts years without a recoat, or a finish that deepens or changes the wood's tone, skip it and look at a pigmented stain instead.
Picture the first hard rain after you've sealed the boards, water just sits in beads and rolls off the edge instead of soaking dark into the grain. That's the whole win, and it's a cheap one to buy. Just go in knowing this is a yearly habit, not a permanent fix, and you'll get exactly what the can promises without any disappointment waiting around the corner.
Amazon shoppers rate it 4.7 out of 5 across 485 ratings. That is their number, not ours.
Before you go
What works better than Thompson water seal?
For longer lasting protection with color options, premium penetrating oil stains and film forming deck finishes built specifically for decking tend to outlast a basic clear multi-surface sealer, though usually at a higher price and with more prep work.
How long will a Thompson water seal last?
Expect roughly a year of protection on an exposed deck or fence before water stops beading and it needs a fresh coat, less on south facing or high traffic surfaces.
What is the best brand of deck sealer?
There isn't one best brand, it depends on whether you want a clear penetrating sealer like this one or a pigmented stain with built in UV blockers, since those solve different problems.
Does Thompson's water seal actually work?
Yes, as a penetrating waterproofer it does what a sealer is meant to do, close the pores in wood, brick and concrete so water beads and runs off instead of soaking in.
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By the numbers
earn an unconditional yes at full priceOut of 135 home & garden products we have reviewed. This one is a yes with a condition attached.
other reviews field the same questionHow long will a Thompson water seal last?
comes up across our home & garden coverage, not just here — one of the things worth settling before you choose.
Verdict datasetQuestion indexCC BY 4.0
Full spec sheet
| Brand Name | Thompson's |
|---|---|
| Model Number | TH.090001-16 |
| Model Name | Thompson's WaterSeal Clear Multi-Surface Waterproofer |
| Number of Items | 1 |
| Number of Packs | 1 |
| Unit Count | 128 Fluid Ounces |
| Included Components | 1 Gallon Sealer |
| Item Type Name | Thompson's WaterSeal Clear Multi-Surface Waterproofer |
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