After testing 8 top deck sealers, I’ve found that the Seal-Once Marine Premium sealer is the best deck sealer for both old and new wood decks.
I performed this testing on the foundation of 15+ years of woodworking expertise.
Through (sometimes painful!) trial and error, I’ve learned how to do everything from building structures with pressure-treated wood to perfecting my millwork.
The reasons I ultimately chose the Seal-Once protectors as my topic pick come down to factors like the product’s convenience and quick drying time, thorough moisture protection, and impressive lifespan.
But, that’s not the whole story: For special use cases, such as old decks and plant protection, I actually have some alternative suggestions.
Keep reading to see a detailed explanation of my top pick, along with the rest of the 8 deck sealer choices!
8 Best Wood Deck Sealers – Summary Table
| Product Image | Product Name | SimpleWood Working Rating | Pros | Cons | Link |
  | Seal-Once Marine Premium | Overall Best Deck Sealer | – Quick drying – Convenient application – Moisture & UV protection – Long-lasting | – Bare wood only – Watery texture | Check Price Here |
 | Ready Seal 512 Sealer | Best Cedar Deck Sealer | – Natural cedar color – Fast application – Temperature resistant – Easy maintenance | – Slow drying – Color fades – Expensive | Check Price Here |
 | Thompson’s WaterSeal | Best Water Sealer for Decks | – Waterproof – Easy to use – UV protection – Transparent finish | – Inconsistent quality – Strong odor – Tacky before drying | Check Price Here |
 | DEFY Crystal Clear | Best Clear Deck Sealer | – UV resistant – Durable – Easy application – Optional cleaner | – Sensitive to sunlight – White residue during drying – Expensive | Check Price Here |
 | Olympic Maximum Stain | Best Deck Sealer for Old Decks | – Weather-resistant – Pleasing color – Simple cleanup – Long lifespan | – Multiple coats required – Spotty coverage – Needs stirring | Check Price Here |
 | Storm System Protector | Best Deck Sealer for Pressure-Treated Wood | – Compatible with many woods – Attractive aesthetics – Strong seal – Affordable | – Weak mix – Slow to dry – Quick to fade | Check Price Here |
 | Eco Advance Exterior | Best Wood Deck Protector for Safety | – Organic ingredients – Fire-resistant – Vapor transmission – Easy to spray | – Thin texture – Short lifespan – Slippery coating | Check Price Here |
 | Rain Guard Paint Sealer | Best Deck Sealer for Weather Protection | – Moisture protection – UV blockage – Temperature durability | – Liquid consistency – Clumpy mixture – Limited application methods | Check Price Here |
8 Best Wood Deck Sealers – Detailed Review
Below, I’ll provide a comprehensive run-down of my experience testing the 8 best wood deck sealers on the market.
For the sake of fairness, I’ll also include some advantages and drawbacks I noticed for each pick.
1. Seal-Once Marine Premium – Overall Best Deck Sealer
The Seal-Once Marine Premium sealer emerged as my top pick for a few core reasons, including longevity, drying speed, and anti-moisture protection.
What stood out to me most was the unorthodox application process. Reading over the label, I was surprised to see that the sealer sprays with a white coloring, but testing confirmed that this quickly dries into a transparent mix.
So, don’t be alarmed by the initial white coloring: It’s temporary!
Pros
- Short drying time. The Seal-Once dries very quickly, almost always within 2-4 hours, which helps cut down on wasted project time.
- Convenience. I was impressed with the convenient number of application options, from a traditional paintbrush approach to both airless and air-assisted sprayers. This gave me a great deal of flexibility and choice as I worked.
- Water protection. By combining a sealer, stain, and finish into one product, the Seal-Once forms a strong barrier against moisture. This prevents mildew and mold, keeping the wood strong and healthy.
- Longevity. Due to its anti-water and anti-UV protection, this sealer can last for several years; a huge bonus for reducing budget costs and time spent reapplying sealants!
Cons
- Use case limitations. Unlike many sealers, the Seal-Once must be used on bare wood, and won’t be effective for painted or stained wood. This unfortunately makes the product unsuitable for a lot of projects, and is its most prominent drawback.
- Watery texture. One frustrating part of my experience was the texture of the sealer. The consistency is quite liquid and led to splashing while I tried to apply part of the deck using a brush.
2. Ready Seal 512 Sealer – Best Cedar Deck Sealer
The Ready Seal 512 Sealer is uncontested when it comes down to the best cedar deck sealer!
Highlights of this oil-based sealer were its beautiful cedar coloring, ability to withstand several climates, and simple application.
One bright side that jumped out to me as I applied the 512 was the fast prep time, which was a breath of fresh air after dealing with the more demanding preparation for the Seal-Once.
Pros
- Natural color. The Ready Seal has a lovely dark, natural cedar hue, which can help reinvigorate the look of old or faded decks.
- Fast application. I was enormously relieved at how quickly I was able to apply the sealer. While a sprayer works well, I actually found using a roller to be the most effective means of applying the product.
- Temperature resistance. The strong, oil coating maintains an effective barrier against both heat and cold damage, so the risk of nasty weather ruining your deck is slim.
- Easy maintenance. Cleanup is quick and straightforward and there’s no need for frequent reapplication. Maintenance won’t be a huge time sink for this one!
Cons
- Slower drying time. Unfortunately, largely due to the oil composition of the sealer, it can take quite some time to dry. In my case, I had to wait for 72 hours before the product fully dried.
- Color fading. The Ready Seal has a known tendency to fade and lose its dark, rich color after roughly a year. This may mean additional, periodic coats are necessary, which obviously is not ideal from a budgetary or efficiency perspective.
- Pricier. As with most oil sealers, this one is significantly costlier than water or cream alternatives, likely putting it out of reach for those with tighter budgets.
3. Thompson’s WaterSeal Multi-Surface – Best Water Sealer for Decks
For the best water sealer for decks, I can’t recommend Thompson’s WaterSeal Multi-Surface sealer enough.
Owing to its strong waterproof formula, clear stain, and simple usability, it places high on my list.
My main takeaway from testing the Multi-Surface was its surprising UV resilience. After applying the sealer to some backyard fencing, I didn’t notice any fading or damage from heat or sunlight.
Pros
- Waterproof. This Thompson’s wood protector creates a strong, watertight seal and prevents moisture from entering the wood and causing mold and mildew damage.
- Ease of use. I was highly impressed with the easy application process. Applying the sealer with an air sprayer required minimal effort and only took 30 minutes.
- Transparency. The sealer includes a transparent finish, which provides the benefit of showing the texture of the lumber while still maintaining a tight seal.
- UV protection. Consisting partly of a UV-resistant coating, the Multi-Sealer will effectively resist sunlight-caused fading and heat damage.
Cons
- Inconsistent quality. The overall quality of the sealer can vary heavily from container to container. Some cans ship with a great consistency and clear appearance, while others contain clumps of white, solid material.
- Strong odor. Right after opening the first container, I noticed the unpleasant, chemical scent. Naturally, this made the application experience much less pleasant!
- Stickiness. Before drying, the texture of the Multi-Surface sealer is unusually sticky and tacky, which can create obstacles for spreading with a brush or roller.
4. DEFY Crystal Clear Composite – Best Clear Deck Sealer
For use cases that require a clear, transparent coloring, the DEFY Crystal Clear Composite is a top contender for the best clear deck sealer.
Factors that lead to DEFY holding this champion title include its zinc-based protective formula, durability, and easy-to-spray water-based composition.
A super positive aspect of the Crystal Clear Composite that I encountered during testing was its custom, accompanying cleaner product. I first applied the cleaner and followed with the sealer, which easily and painlessly formed a seal with the wood.
Pros
- Heat resistance. As a result of its zinc-heavy chemical formula, the Crystal Clear Composite is highly protective against sunlight, preventing cracking and other UV-caused damages.
- Durability. Manufactured with higher-quality resins, this DEFY wood protector generally lasts for several months before a maintenance coat, which minimizes the amount of time spent reapplying the sealant.
- Easy-to-apply. During the process of applying the sealer, I was impressed with the ease of use. The maintenance coat was also simple to spray on, as it required no stripping of the wood surface before use.
- Optional cleaner. DEFY offers an optional cleaner product, the Defy Composite Deck Cleaner, to prep the lumber for sealing. The main advantage of this is that it eliminates the need to search for a separate cleaner.
Cons
- Sunlight-sensitive application. While the sealer is highly sun-resistant once fully dried, it actually can’t be applied while there’s direct sunlight. As you can imagine, this greatly restricts the time of day that you can apply the product!
- White residue. I was unpleasantly surprised to notice distinct white spots forming during the drying process. These fortunately went away after the wood was fully dry, but it made me wonder if there’s a problem with the formula.
- Expensive. There’s no getting around it: The DEFY sealer is unusually pricey for a water-based protector. Whether that price tag is justified ultimately comes down to your budget and project needs.
5. Olympic Maximum Stain and Sealer – Best Deck Sealer for Old Decks
If you’re working with an older, perhaps even slightly run-down deck, not to worry: The Olympic Maximum Stain and Sealer is the best deck sealer for old decks you’ll find!
Working with the Olympic sealer, I found myself particularly enthused by the deck protector’s cold and moisture protection, striking redwood color, and straightforward cleanup. I also couldn’t help but notice the extensive longevity, with the seal holding up perfectly even months later.
Pros
- Weather-resistant coating. This Olympic sealer is designed with cold and moisture protection that allow the seal to withstand a rain storm even only 8 hours after application. This is good news for those who live in cold areas and want to keep their lumber strong!
- Pleasant color. Displaying a natural redwood tint, this stain is a good choice for front-and-center projects that call for some aesthetic finesse.
- Simple cleanup. The composition of the protector allowed me to complete a straightforward, basic cleanup with just soap and water. No industrial or toxic chemicals needed!
- Lifespan. If applied properly, the sealer can maintain its protective qualities for several years, erasing worries about applying constant maintenance coats.
Cons
- Requires multiple coats. Due to its thin consistency, any surface the Olympic sealer is applied to typically needs more than one coat. This can use up the product quickly and end up forcing you to buy more!
- Spotty coverage. The stain can be a bit difficult to spread around, sometimes leading to some parts of the surface getting a thicker coat than others and creating an uneven, potentially weak seal.
- Needs stirring. In my case, upon opening the container, I needed to mix it up a bit with the included stirring stick to get it in a usable state. It was only a mild inconvenience, but still noteworthy.
6. Storm System Protector – Best Deck Sealer for Pressure-Treated Wood
Pressure-treated decks and structures come with their own set of hurdles, but there’s a silver lining: The Storm System Protector offers a compelling contender for the best deck sealer for pressure-treated wood.
Among the sealer’s most appealing traits are its compatibility with several types of lumber, striking visual appearance, and strong protective seal.
All of these strengths add up to an effective recipe for a long-lasting pressure-treated wood sealer.
Pros
- Wood compatibility. This wood protector conveniently works well with many types of lumber; pressure-treated wood, cedar, pine, redwood, and mahogany are all on the table. If material flexibility is essential to you, this sealer should be near the top of your list!
- Aesthetics. With a rich, attractive black walnut hue, the Storm System sealer is ideal for projects that you want to show off to guests and visitors.
- Tough seal. My test of the sealer confirmed that it incorporates a strong protective formula, capable of holding off moisture and heat.
- Affordability. While still more expensive than most water-based sealers, this protector is quite reasonably priced for an oil sealer, especially given its material flexibility.
Cons
- Weak mix. Upon opening my first Storm System container, it immediately became apparent that the product didn’t stay properly mixed during shipping. This was easily remedied with some stirring, but make sure to check the mix before applying the stain!
- Slow to dry. Drying can take several days, depending on weather, so this is likely not the best choice when you’re working on a deadline.
- Quick to fade. Though the protector’s color is beautiful, it has an unfortunate tendency to fade and lose its luster within months.
7. Eco Advance Exterior Spray-On – Best Wood Deck Protector for Safety
Those who are highly conscious of the effects sealers can have on nearby plants and wildlife will find a friend in the Eco Advance Exterior Spray-On wood deck protector.
This sealer makes a concerted effort to avoid plant damage by utilizing a non-toxic chemical formula, vapor transmission abilities, and fire-resistant properties.
Using the Eco Advance myself, I was highly satisfied with its accurate marketing. True to the company’s word, the product did no noticeable harm to any of my nearby garden plants after I applied it to wooden fencing.
Pros
- Organic ingredients. Consisting exclusively of nontoxic, organic ingredients, the Eco Advance spray ensures any plant or gardening projects you’re working on remain unharmed.
- Non-flammable formula. With its flame-resistant formula, the sealer reduces the risk of a structural fire and resultant damages.
- Vapor transmission. By using siloxane, the spray allows for vapor transmission, which produces breathing space for the lumber and helps lock out mildew-creating moisture.
- Easily sprayable. I was quite relieved at the sheer ease of use for the spray; a basic garden pump sprayer was all it took to quickly coat the wood surface.
Cons
- Thin texture. As a result of the Eco Advance’s thin consistency, it almost always calls for multiple surface coats, which can drain your sealer supply.
- Shorter lifespan. Unlike some of the more durable choices on my list, this deck protector typically only lasts a few months before needing a new coat. Not exactly convenient!
- Slippery coating. One spectacularly unexpected hurdle with the sealer was its waxy coating, which made it difficult for me not to slip on my deck as I walked over it.
8. Rain Guard Paint Sealer – Best Deck Sealer for Weather Protection
Climate and the elements can be a tricky factor to defend against, but the Rain Guard Paint Sealer certainly gives you a fighting chance!
Points of interest for me were the sealer’s water and temperature protection, UV barrier, and wind resilience – all of which combined to make this a slam dunk of a weather-resistant deck sealer.
Pros
- Moisture protection. Using a special proprietary formula, Rain Guard is able to form a hydrophobic seal, keeping out water particles and staving off rot and decay.
- UV blockage. The hydrophobic seal mentioned above also works quite effectively against sunlight and UV rays, slowing down the process of color fading and wood warping.
- Temperature durability. After testing for different temperature conditions, I confirmed that the sealer is both heat and cold resistant, providing flexible options for outdoor projects.
Cons
- Liquid consistency. Rain Guard shares an issue with several deck sealers, which is the thin consistency, leading to several coats of sealant and additional funds spent on restocking the product.
- Clumpy mixture. Despite the watery texture, solid clumps of sealant often form in the container and clog up sprayers.
- Limited application methods. On account of the clumps, I found that this deck protector is extremely difficult to spread with a roller, which limited me to using a sprayer as my only option.
Guide for Choosing the Best Deck Sealer
While this list is a helpful start, everyone has their own use case and personal preferences to consider.
Let’s expand on two areas to consider when picking the best deck sealer: Features and uses!
Top Features to Consider
In my experience, there are three broad feature sets you’ll really want to focus on as you narrow down a deck sealer – Price tag, sealer application, and lifespan.
Price
Never overlook the importance of affordability!
Picking an expensive option can blow up your budget and create project obstacles that extend deadlines, hurt your bottom line, and lead to lackluster results.
Common variables that I’ve found to most strongly correlate with a deck sealer’s price include:
- Quantity. Perhaps unsurprisingly, a 5-gallon sealant container will almost always cost more than a 1-gallon container, so, if you infrequently use sealers, picking a smaller product is a great way to cut down on cost.
- Formula. If your deck project doesn’t demand a specific material formula, consider opting for an oil-based sealer, as these typically cost less than cream or water formulas.
- Brand. More popular brands can often get away with a higher price tag, on account of consumer trust and loyalty. If you’re willing to take a gamble on quality, a lesser-known brand might help out your wallet!
Ease of Application
While it’s tempting to dismiss ease of use as something trivial, a difficult-to-apply deck sealer can make your project take much longer and create a highly unpleasant experience.
The two main measures to compare a sealer’s ease of use are drying time and application method.
Drying time is simple enough: The less time spent on drying, the faster the whole project goes!
For quick drying, you’ll generally want to choose a water or cream sealer instead of an oil-based product. I once used an oil sealer for my backyard deck and was dismayed when it took 3 days to fully dry and cure!
When it comes to application methods, sprayable water sealers are highly convenient. As with drying times, oil sealers are the less practical option.
Durability and Longevity
The benefits of longer-lasting wood deck protectors are a no-brainer!
Not only is it more convenient to not have to reapply the sealant, but avoiding continuous reapplication also saves money on restocking your supply.
As you compare sealers for durability, pay careful attention to the formula and product description.
Clear oil sealers typically protect against the elements more effectively than other formulas.
For example, that oil deck sealer I mentioned earlier? It may have taken ages to dry, but, on the other hand, it kept my deck’s lumber healthy and strong for several years afterwards!
Common Uses for Deck Sealers
Choosing the best wood deck sealer also requires examining your use case.
Let’s go through a few of the most frequent uses for these sealers:
Preventing Rot and Decay
One of the most essential functions of a deck sealer is keeping wood healthy for an extended time. By sealing the lumber, mold and mildew are much less likely to form and damage the structure.
To find a sealer that will keep your timber rot-free, you’ll likely want to look at oil-based sealants, as they form a stronger barrier against moisture damage.
Weather and Heat Protection
When I was just starting out with woodworking, I was unaware of just how damaging UV radiation and heat could be to wood.
This knowledge gap ended up costing me more time, money, and patience than I could have imagined!
While water and cream sealers definitely help against sun and heat damage, oil sealers are typically the better choice. They create a stronger barrier that surrounds the wood, keeping it safe from UV rays.
Enhancing Appearance
Sealers aren’t only used for practical functionality! Appearance is also a huge cornerstone of their appeal.
When combined with natural-looking pigment and used as a stain, deck sealers can create a rich, vibrant appearance without detracting from the natural color of the wood.
This is especially helpful for more attractive types of lumber, like oak, cedar, or walnut, as it can help accentuate their natural color while making it more vivid.
Conclusion
For most types of projects, the best deck sealer you can choose is the Seal-Once Marine Premium.
Despite some minor drawbacks like its highly liquid consistency and demanding preparation requirements, I can confirm that the Seal-Once sealer offers several key benefits, including convenience, protective anti-moisture coating, and longevity.
Overall, these benefits worked together to rocket this sealer to the top of my list and achieve the title of best deck sealer.
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