Best Outdoor Wood Sealer For All Purposes

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You’ll probably want to protect most of the projects you make with a sealant, but finding and applying the best outdoor wood sealer doesn’t have to be as complicated as it may seem. For some projects, such as work benches, there’s no real benefit to applying sealant, but for furniture and decks it is invaluable.

Thompsons – Best deck stain (Amazon)
Miniwax Urethane Sealant – Best indoor/outdoor wood sealer (Amazon)
Rust-Oleum – Best outdoor wood sealer (Amazon)

However good these particular products are, the best wood sealer is only as good as the job it’s meant to perform. Meaning if you are in an area that is prone to heavy amount of rain, then you’ll need a sealant that protects against water damage. If you are in a relatively dry area without much shade, then you’ll want one that prevents sun damage.

Regardless what you need the best exterior wood sealer for, this review covers several different options to choose from that help preserve your wood projects.

Finding the right sealer

Determine what you need it to do. How any one product claims to be the best outdoor wood sealer is beyond me. As previously mentioned, options vary based on needs. To protect against liquid, film finishes are a better option than oil finishes, but the down side is they’re harder to refinish and repair. Which leads me to my first point of consideration

How long the primer lasts before you have to reapply, not to be confused for when you apply coats. While all sealants and stains need to be applied at some point, it’s important to ensure the wood is preserved from outdoor weather damage thoroughly. Average time resiliency is improved with UV blockers and other protective barriers to prevent moisture damage.

Choosing a water or oil based sealer is important because the result is variously different, and understanding what their strengths and weaknesses are will help provide you with an informed decision. The best outdoor wood sealer is determined by the job you need it to do.

Water Based Sealer

• Provides thorough protection
• Clear coating (remains clear over time)
• No harmful odors
• Short dry time (less time to penetrate fibers)
• Clean with water

Oil Based Sealer

• Provides thorough protection
• Amber coating (gets yellow over time)
• Emits potentially harmful odors
• Long dry time (more time to penetrate fibers)
• Requires mineral spirits to clean

1. Miniwax Indoor/Outdoor Urethane Sealant – Diverse application

(Water based option)

I understand that because this is an oil based sealer that its indoor application would emit some strong odors, however this post is about the best outdoor wood sealer I feel I would be doing my audience a huge injustice by not mentioning this Miniwax sealer. With the indoor application aside, I wanted to mention that this sealant has significant resistance to weather damage making it an even better option to apply to your outdoor projects.

Miniwax Urethane Sealant contains UV blockers that prevents long-term discoloration and fading in the wood. Locations where sun exposure is prominent need products with UV blockers to preserve the condition and color of the wood. However, the Miniwax sealant is actually quite diverse and isn’t only for warm climate regions. The oils adapt to the the temperature change during the seasons by contracting and expanding with the wood.

The clear coat goes best over light-colored woods. Ideally, the Miniwax is applicable with a variety of things, but here are a few:

• Doors
• Windows
• Trim
• Fences
• Cabinets
• Counter tops
• Outdoor Furniture

You are able to apply the sealer to wood that has paint or finish already on it, assuming it is dry. Regardless if that particular application was water or oil based. Whether it’s indoor or outdoor, the Miniwax option is the best outdoor wood sealer for its diverse application and it’s too convenient not to have for future projects.

2. Thompsons WaterSeal Natural Wood Protector – Best Deck Sealer

Thompson’s WaterSeal is comparably more industrial, but that comes with the growth of the company itself. Consequently, their advanced wood protector tackles problems most often encountered with outdoor wood projects. Reason why this is essential to have is because wood is most vulnerable outside, and without solutions to protect it, you risk preservation of the wood. When placed outside, it is exposed to a number of influences that can potentially ruin it, such as rotting, termites, and most importantly weather damage. 

The specific area of focus for Thompson’s WaterSeal is water damage, so you can be guaranteed its coat resiliency against mildew and water damage is almost unparalleled. The waterproofing coats flourish even in environments where rain is most prevalent. It claims to be a “one coat waterproofer”, however we all know one coat is never sufficient.

On the flip side of that, it is also great at combating UV damage even after long exposure to the sun. Sun damage is a bit of an ambiguous reference to some people, but what it basically does is destroy the necessary component of wood that strengthens its cell walls called lignin. In other words, it fades the wood. The fact that it prevents wood from fading means it is a penetrating sealer as opposed to one that just sits on the surface. As you can probably already guess, this sealer is the best wood deck sealer for outside furniture, and general exterior wood. 

3. Anchorseal 2 Hybrid Logs & Lumber – Best End Grain Sealer

As the big bold letters on the front of the gallon bucket suggests, this is the best end grain sealer that can also be applied to wood bowls and carvings. Anchorseal 2 is a hybrid derived from plant based polymers and wax that has been around since 1980 and is the highest acclaimed end sealer for logs and lumber. Its primary objective is preserving the wood, obviously, but more specifically it prevents 90% of checking and splitting on ends. This specific issue isn’t as widely illustrated because it seems to be, at most, a minor inconvenience, but ,contrary to the belief, it can cause additional and detrimental problems that extend past just the ends of the wood. 

Depending on the wood species, overall coverage per gallon of Anchorseal is approximately 100 square feet. Aside from solely applying this to end grain, additionally it is compatible for turning blanks, wood bowls, and carvings. As an environmentally friendly, water-based sealer (non-toxic/non-hazardous wax) it can also be applied inside, but the frequency of its interior usage won’t match the amount of applications it can be used for outside. It’s important to note that this particular sealer is best for hardwoods. 

Cleanup solutions are quick and minimal by using just soap and water for that process.

4. Seal Once Marine – Best Waterproof Sealer For Wood

Resiliency is the name of the game if your primary goal is achieving longevity against the wetter days. Claimed as the one true product by Seal Once Marine, this premium sealant is the best waterproof sealant is used to prevent decay, mold, and any additional water damage. It’s matched well with high moisture areas like piers, docks, lake, or even if you experience a lot of rain.

Apply multiple coats to achieve an ideal penetration and waterproofing of the wood. This creates a malleable, breathable barrier that prevents rot, decay, mold, and wood splitting by allowing moisture to escape. I interpret its waterproofing capabilities as a green light for outdoor use, but I’ve come to find it is an excellent water-base sealer for indoors as well.

Its interior compatibility is partially because it is non-toxic when dry/fully cured. When applied, it develops a protective, elastic finish that works as a sealer, primer, tie-coat or paint additive that enhances adhesion against ordinary spills, moisture and foot traffic. Additionally, its adhesion to more exotic woods that are oily and dense (think teak, rosewood, ipe, etc.) is remarkably exceptional.

As far as coverage is concerned, one gallon is good between 250-350 square feet per coat. It’s difficult to say exactly how many times you’ll need to coat the wood because that greatly depends on its pores.

5. Ready Seal Stain & Seal – Best outdoor wood sealer

Here’s a great oil based, semi transparent two for one product by Ready Seal with a variety of stain colors that match the wood you’re applying it on. As the name suggests, this product works as both a sealer and a stain. The benefits of this alternative method can mainly be attributed to convenience and cost efficiency. Using and applying a sealer and stain separately have no real significant advantageous on their performance, so save some time and money.

Ready Seal’s outdoor compatibility at first seems so extensive that you’d believe they thought of every possible obstacle when it comes to wood and weather damage (UV blockers, water proof, mold and mildew resistant, no laps, runs, or streaks). It is perfectly able to be applied in any weather but does need 48 to 72 hours of dry time. Do not apply Ready Seal over a painted or newly stain surfaces, this will inhibit wood penetration. I typically get 2 years out of this particular stain sealer before reapplication is necessary. 

Method of application is up to you, it can be sprayed, rolled, brushed onto the surface. Keep in mind that the solution is darkest when initially applied and reaches its actual color after 14 days.

Aside from all the features, if you have an outdoor project and want to quickly and thoroughly preserve the wood’s beauty without all the extra steps then Ready Seal can tackle anything.

6. Bona ClassicSeal

The Bona ClassicSeal operates the exact opposite way that you might anticipate it would. Since it was developed as a three-coat water-based system, using it for all layers isn’t going to save you any money. Intead, it serves as a primer like base coat that bonds with other layers and does not go on the top outer layer. The viscosity isn’t as dense as Bona’s topcoats (Mega or Traffic) which benefits the wood a lot more because it really soaks into its pores and attaches to it more effectively. Even though those topcoats aren’t as adequate at holding onto the wood as a sealer, they do adhere well to this sealer. Consequently, polyurethane layers need to bond to each other in order to be protective. 

The Bona Mega and Bona Traffic are complementary products in the three-coat water-based system, so the Bona ClassicSeal is the foundation coat only of this trio. This essentially sets up the other two for success.

Similar seal coats prevent “side-bonding”, the habit of gluing boards to one another along their edges by strong finish coats, additionally preventing even gapping floorboards during the dry periods of the year. Topcoats have the potential to strip the tannin from the grain and into the finish, resulting in a blotchy appearance, so it is very important that sealers are a first coat on oak woods. 

There are six separate sealers made by Bona, all under-colors varying slightly. ClassicSeal has the clearest out of all six. It being a water-based sealer, it does not have the warm, amber tone that oil-based or polyurethane options do. However, one aesthetic effect that is true about this sealer is that it doesn’t hide any underlying pink hints of red oak. While neither a positive or negative result, it is important to know before using it, and if color in your wood is important, then stain the wood first because you are not able to tint this coat.

ClassicSeal and sanding aren’t compatible, you’ll see that by taking a traditional buffer and some abrasive underneath the ClassicSeal clumps similar to rubber cement. It’s an obstacle necessary to avoid if the grain raises or felt too rough, but thankfully the solution to it is pretty simple. What I discovered to work the best is to use a steel wool and sandpaper mini sheets as a combination to keep the wood cool and prevent any clumping.

7. TriCoPolymer Non Toxic Wood Sealant – Best Environmentally Friendly Sealer

Most viable sealer capable of replacing any toxic products comes from a company called TriCoPolymer. It is used any and everywhere from home-owners to theme parks and has been independently tested by National Labs and contractors alike. All concluding results meet IAO indoor air quality requirements and is non-flammable making it safe for pets and their owners. Additionally, it is the staple sealer for wall cavity renovations, natural weather conditions up to severe conditions (think hurricanes), and doesn’t dissipate. 

The non-toxic Clear Satin Cedar sealer (tongue twister), intentionally works with Cedar and other woods that have high oil content. It’s formulated to be the best outdoor wood sealer for any outside structure. All excessive moisture is gradually passed from the film and out of the wood to stabilize it. This allows it to maintain its oil content for many many years, although natural “graying” will take place if applied as a solo clear coating. Only apply with other water-based stains.

• Best with high oil content wood (ex: red wood cedar)
• Reduces splits, warping, spalling/twisting, and retains oil content
• USDA/FDA compliant
• 600 sq ft. coverage (spray)

Raise wood grain of raw lumber, in order to allow it to sand off, by applying water to its surface, let it dry, sand, and repeat to reach desired result. Afterwards, seal it. You’ll sometimes see that economy cut wood boards are always rough because of crosscutting grains. By sealing it, it assures that moisture is kept from ruining the core. 

8. Rust-Oleum Zinsser Bulls Eye Sealcoat – Best Indoor Wood Sealer

Zinsser Bulls Eye Sealcoat is a universal sanding sealer, for indoors, that implements 100% wax-free shellac. As a result, this particular primer dries incredibly fast and is compatible over or under all clear wood finishes. Its coverage is a surprising 400-600 square feet per gallon, but this comes in quarts which comes out to roughly 100-150 square feet per quart. Long-term exposure has proven to significantly enhance the preservation of the wood’s beauty.

There’s a couple points that make Zinsser Sealcoat significant. Firstly, its compatibility with clear finishes is a relatively underrated blessing. Often times indoor furniture and floors use clear coats so by having this sealer it adds a protective layer making it smooth. Secondly, a well known problem with sealers is the eventual discoloration as it ages. Fortunately, this one does not darken or yellow over time. Lastly, and most conveniently, the clean up process is hardly the mess you might expect. All that’s required is either alcohol or ammonia and water. 

Zinsser could quite possibly adopt the title of the best indoor wood sealer for 2020 because of how beneficial it is for conserving the nature of the wood. Basically, it stabilizes the grain by closing small pores and fills out minor scratches before additional coating or sanding. Applying it is a fairly quick process, given the water-like consistency, even for relatively meticulous projects without the time-consuming cleanup. 

In addition to its wood preservation, dewaxed shellac has an essential role for sticking to practically everything and also takes almost anything on top, such as water-based and oil-based polyurethanes. This is important because a top coat of shellac can prevent fish-eye problems and other similar issues.