June 12, 2021

Best Outdoor Wood Sealer | Product with Buyer’s Guide

Are you looking for the best outdoor wood sealer? I had often wondered what it takes to keep outdoor furniture looking pristine. When wood is outside, it is susceptible to rotting and other damage. That is because of the outdoor elements. Deterioration is part of the deal when you, Yet, there is a way to ensure that your wood is protected. 

In this article, we take a look at the best outdoor wood sealer. We will look at various products and what we like and don’t like. Also, we will look at the reasons why we want a particular one. Let’s dive in.

Top Pick for the Best Outdoor Wood Sealer

After going through the different wood sealers on our list, our top pick is the Rain Guard Premium Water Sealer – Eco-Friendly Bargain Option. We like that it comes with a five-year guarantee. The manufacturer is confident that it will protect your wood for a reasonable time. Also, it needs little to no maintenance. I find this handy, especially with outdoor furniture and decks. 

Best sealer for outdoor wood furniture Round Up

UC Coatings Corporation Sealer

The Nano-guard sealer allows the wood to age naturally. It does not decay as it ages. The sealer penetrates the wood surface deep. That protects and stabilizes the wood material against harsh weather conditions such as rain and sun. 

It coats the wood at the cellular level. The material is stabilized by eliminating warping and cupping. The sealer forms a breathable barrier that gives room for the expansion and contraction of the wood. 

Water vapor is allowed to escape. The sealer preserves the natural state of wood by shunning rot, decay, mold, and mildew growth. It is easy to clean. Use water, soap, and cloth. It controls the rate of moisture.

S.1 Clear Sealer

S.1 is a two-part clear sealer that penetrates through the wood. It is waterproof. That means you do not have to worry about exposing your wood to wet conditions. The sealer makes your wood usable above and below the waterline. 

That matches with the requirements of outdoor activities. These include boat building, beach buildings, and garden furniture. Use the seal following the assembly of the wood item. The movement of the wood becomes limited. 

The chances of having water underneath the wood are low. That prevents molds from growing and destroying your finish.  The mix ratio is easy to follow. It is 1:1, and the coverage is 75 square feet per quart. 

Waterlox-Medium Sheen sealer

It is an oil-based sealer that penetrates through the wood by closing holes inside. Work with a brush so that it becomes easy to apply. Other materials used by the seal are a cloth, lambswool applicator. 

A spray substitutes the cloth roller. The moment the sealer penetrates, it becomes waterproof. The waterproof is durable. It is a finishing system of multiple coats and works as a primer coat. It is compatible with the Waterlox marine finish. 

It is easy to apply, and it is tung oil-based. It is non-toxic. The sealer gives a medium sheen which is a gloss level that fades. The sheen sealer protects wood from moisture and foot traffic. 

Marine system Three-Spar

The urethane seal protects the wood against marine environments. That is saltwater from the sea. It is protective of outdoor projects. It contains UV absorbers and additives that strengthen wood to fight against natural disasters. 

It also varnishes wood surfaces and gives them a shiny finish. That makes it ideal for outdoor furniture. Sealing wood with the Marine does not allow moisture inside, but it provides room to breathe. 

Micro-fissures allow a small amount of moisture to get inside, but it does not allow expansion. It works magic with the coat. That combination gives an excellent base to the structure. 

Seal IT Green Sealants Wood

It is a wood sealer that works on all types of wood. It penetrates deep inside the wood, closing room for toxic substances. It produces natural oils that shun moisture and insects. The seal creates a bond with the wood. It does not have harmful chemicals. 

That makes it safe. That preserves the natural environment. Plants are safe, and the ingredients are safe. It is ideal for professional use.  It is easy to use. Clean the wood if it is dirty. Let it dry for an hour. Apply the seal with a deck pad. It is durable as it lasts for more than ten years. 

It is safe to apply for outdoor furniture since it does not affect pets. Leave it dry so that it does not affect your environment. The wood is resistant to cracking, cupping, or curling. It does not contain heavy material. That does not add weight to the original weight. That is the reason why outdoor furniture becomes easy to move. 

Storm Protector Sealer

Storm sealer is an oil-based semi-transparent that maintains the original color of the furniture. It is a 2-in-1 sealer that stains wood as well. That gives maximum protection and adds highlights to the natural beauty of the wood grain. 

It makes deep penetration into the wood. That protects the wood against natural disasters. The seal is compatible with Mahogany, cedar, redwood, and cypress. These are durable types of wood that are perfect for outdoor furniture. 

That makes hybrid furniture that stands against the harsh conditions. It is ideal for deck, fences, and siding. Versatility describes the sealer as it also works as a wood fence protector. It is easy to apply with a brush or a roller. It comes with UV protection. 

Deckwise Oil Seal

Deckwise oil seal works on exterior hardwood and thermal wood surfaces. Hardwood is perfect for outdoor furniture. It contains trans oxide pigment that gives a brown tint for UV defense. 

The sun does not affect the furniture. It enhances the natural beauty of wood furniture. It is odorless and penetrates through the wood. It is free from mold and mildew. The coating process is easy. 

When the application dries, the furniture does not crack. For exceptional results, use it on Ipe and tigerwood. The seal is thick to give you a thick coating. 

Thompsons Water Seal

Thompsons is a transparent waterproofing stain that prevents outdoor furniture from water damage. It is advanced in the manner in which it gives fade-resistant color. The coating is resistant to mildew and UV damage. 

Make sure the wood surface is clean and dry. It meets the standards of industry waterproofing wood. Complete outdoor wood protection is given. The stain replaces the water beading feature. One coat is enough for exterior wood. 

The chances of having the natural color fade are low.  The directions for applying are easy to follow. One coat is enough for outside furniture. Re-coating is recommended.  

Rust-Oleum Seal

Rust-Oleum is an oil-based gloss that protects outdoor furniture such as railings. It gives maximum protection and durability to the wood surface. An even finish is a bonus to the wood furniture. 

It takes two hours to dry and has coverage of 190 square feet. You are allowed to add another layer of coat after 8 hours. The formula is resistant to weather and the sun. It contains UV resistance substances. 

The surface is protected from graying with age. It maintains its natural color for ages. The gloss furnish beautifies your garden due to a polished and clean look added onto the furniture.

Eco-poly Polyurethane Sealer

The Eco-poly sealer is not only a sealer but also a high-quality surface finish that gives concrete surfaces. The sealer is resistant to scratch, crack, and moisture. It is also resistant to chemicals. 

The UV repellent chemicals protect outdoor furniture from sunlight. There is a long-lasting shiny finish on your furniture produced by the sealer. It has a low odor and water-based polyurethane. It dries faster than an oil-based sealer. 

It gives multi-layers of protection that is durable. A minimum of two coats is needed.  The making process of the sealer is advanced, and it excludes toxic gases. That makes it safe for human contact.

Seal-Once Marine 

This wood sealer can be described as penetrating. It also acts as a waterproofer and stain. It is a water-based wood sealer that is often chosen for its low VOC formula, which works pretty well, especially in places exposed to a lot of moisture. Wooden furniture left outside is often susceptible to weather and moisture damage. This wood sealer is specially made to mitigate this. 

It is non-toxic and this, therefore, makes it safe to use around both people and pets. When compared to oil-based sealers, it has similar benefits but without the danger of toxins. This sealer helps to protect and also enhance the appearance of the wood. Also, it may help to stabilize the wood. 


  • It is non-toxic
  • It helps enhance the natural look of the wood.
  • It protects the wood from weather and moisture damage.
  • It stabilizes the wood.
  • It lets the wood age naturally while protecting it. 


  • It is on the higher ends of pricing. 
  • It may not last as long as the manufacturer claims.

Eco Advance Wood Siloxane Waterproofer – Concentrate

This wood sealer comes in liquid form. It’s a concentrate, which means that a little will go a long way after you have diluted it. You can use it on wooden decks, plywood, as well as different types of wood. It is water-based and non-toxic, making it safe to use. Also, it is non-flammable and will not harm any plant life.

This sealer is also breathable, and as such, the wood can grow gracefully and naturally. It serves to protect your wood against weather damage, stains, mildew, sea salt, and other outside weather elements. 


  • It is safe to use around people and pets because it is non-toxic.
  • It is non-flammable
  • It protects the wood.
  • It is easy to use
  • It is sprayed on


  • It may not work as well on all types of wood. Some customers have experienced problems with cedarwood. 
  • It may not protect the wood as well as the manufacturer says it does. 

Rain Guard Premium Water Sealer – Eco-Friendly Bargain Option

One thing to look out for when getting a wood sealer is how long it will last. You don’t want to have to be going back to seal the furniture or wood a few months down the line. That can get tedious. 

Rain guard premium comes with a five-year guarantee from the manufacturer. It protects the wood from the harsh precipitation weather elements. 

This is a concentrated formula, meaning you can get more from just one bottle when diluting it. You can use a sprayer, brush, or roller for easy application. Also, it requires little to no maintenance. It is clear, and as such, there is a chance of accidentally staining your wood with the wrong color. 


  • It will not change the appearance of the wood. 
  • It protects the wood from moisture, efflorescence, mold, and mildew. It repels water.
  • It’s a concentrated formula that can be diluted and hence go a long way. 
  • It has ultraviolet or UV stabilizers.
  • It is clear in color. 


  • It doesn’t come in different stain colors.
  • It has to be mixed with water. 

Defy Crystal Clear Composite Deck Waterproofing – Best for Composite Decks

This wood sealer is water-based and transparent. This way, you can apply it and not worry about the wood taking up a color you don’t intend. It is made of resin that helps keep the wood safe from fading as well as darkening. It is fortified with UV-blocking nano zinc particles. The zinc particles in the formula help protect the wood from the sun’s rays. It also prevents fungus from growing. 

One of the things that makes this an excellent buy for us is that it is easy to use and easy to maintain. It is a versatile waterproofing solution for your outdoor wood. However, the downside is that it is only suitable for composite decks. It is not as versatile as other wood sealers. 


  • It is made of durable resins.
  • It is versatile
  • Its clear color keeps the wood color visible and also does not alter the integrity of the wood.
  • It is easy to maintain
  • It is fortified with zinc nanoparticles. 


  • It is better suited for composite decks only.
  • It is on the high end of the pricing.

Buyer’s Guide

Buying a wood sealer requires looking for a couple of necessary features. This is why we have put together this buying guide to know what you need to look for. It doesn’t need to be rocket science, just a matter of making an informed decision. 

How wood sealer works

Before you commit to a particular wood sealer, it helps to know how it works and what you can expect from it. A wood sealer needs to be applied to the wood that you want to be protected. Check on how to apply the brand that you are considering. If you are working on a large area, such as a deck, you want to get a wood sealer applied in large amounts to cover a large area faster. 

The wood sealer works by penetrating the wood pores, soaking it in liquid form. When it dries and hardens, it then reinforces the wood surface. The way it works depends on the porosity of the wood and the sealant’s viscosity. These two factors will help determine the time and how well the wood is sealed. 

While sealers are made by different manufacturers, reading the label can help you understand how to use them. Some wood sealants combine stains as well, and as such, it is also something to look out for. To retain the wood’s original color, you may want a clear wood sealant without a stain.

How to apply wood sealer

  1. Before applying a wood sealer, the first thing that you will need to do is to make sure that the surface that you want to seal is clean. Wipe it down if necessary. Just be sure to check with the sealer if you can apply it to wet wood or if you need to let it dry first. If the surface is dirty, it may be hard for the sealant to stick to that part, so be careful to clean it. If the wood has had an adhesive or some type of finish applied to it previously, then you will need to remove that, leaving the wood surface” naked.”
  2. Also, make sure that you have protected any close areas, which you do not want the sealant to get onto. 
  3. Then, check to see if any wood parts need to be repaired or fixed before you start sealing them. 
  4. If you have any plants around, you may want to water them so that if any sealant finds its way onto them, it gets diluted and won’t harm them as much. A more full-proof solution is to look for a sealant that is non-toxic and safe to use around plants. 
  5. One of the best ways to apply wood sealer is to paint it, which you would do with paint. For this, you will need a soft brush with even bristles to spread the sealer around. Sealer often dries fast, so you want to make sure that the brush you use is quick and efficient. You really will not have the time to go back for the finer detail. 

What should a wood sealer for outdoor wood feature?

  1. Look for a sealer with good ultraviolet or UV protection: You want to ensure that the wood sealer you get has suitable properties. These include finding a sealer that will protect the wood against the fading brought on by the sun’s light. 
  2. Water-resistant: Look for a sealant that can protect the wood from outdoor elements such as rain and snow. Outdoor furniture is exposed to mold and mildew, so you want to ensure that the sealer can protect the wood sufficiently from moisture. 
  3. Non-toxic: Also, consider getting a wood sealant that is non-toxic and safe to use around plants, lawns, pets, and people. This is particularly important for furniture that people, including children, will operate. If the sealant is toxic, it may cause long-term health effects which you don’t want.
  4. Length of time: You also want to look for a sealer that lasts a while. Some last for months, while others last for years. I prefer wood sealers that often don’t need to be reapplied for larger surfaces. 

Final Thoughts

Sealing exterior wood is a great way to protect it from the elements like rain, sun, or snow. It’s also fun to add color to your wood when you use a sealer that is also a wood stain. Keeping moisture away from your wood can greatly extend the life of your furniture, deck, or any other wood surface.

We looked closely at some of the five best wood sealers for outdoor furniture and examined what makes them stand out and what does not. We recommend that you stick with reputable manufacturers known for making wood sealers that do the job. We hope this helps you find the perfect product for you and the wood you want to seal. Have fun sealing wood!

David D. Hughes

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