12 Most Effective Wood Sealers According To Experts

Published September 9, 2023

From houses to furniture and even decorations, humans had been using wood to build stuff for centuries. Not only is it durable, but wood is also one of the most flexible materials you can work with. Plus it adds a classic appeal to any building.

Yet despite its advantages, it has one major drawback. Unlike concrete, plastic, or metal, it’s not impervious to the elements. Changing weather, humidity, and temperature can cause it to shrink or expand. As a result, it loses its shape and may even get warped or twisted. Outdoor furniture, doors, sheds, or any type of wooden stuff that’s constantly exposed to the elements are especially prone to it.

This is where wood sealers enter the picture. They seal up the wood’s surface preventing it from soaking up water and moisture from the environment. This preserves the internal structure of the wood which, in turn, prevents it from losing its original shape – no matter the season.

But with so many wood sealer brands in the market right now, choosing one can be difficult. Especially if you have no background in woodworking. To make matters easier for you, we’ve scoured the web for recommendations from woodworking experts. According to them, these are the nine most effective wood sealers:

1. Thompson’s Water Seal

Thompson’s has been a trusted brand for wood and concrete waterproofing products for decades. This is why in most woodworking blogs, their water seal always tops the list of recommended wood sealers.

Aside from resisting most types of mold and mildew, it’s also long-lasting. So you won’t have to worry about reapplying a sealer every couple of years. It also applies to both dry and damp wood and can be used on outdoor furniture, decks, doors, and fences.

Pros:

• Trusted brand
• Long-lasting
• It can be used on various outdoor surfaces.

Cons: 

• A bit pricey
• It may require reapplication after a few years

2. Rainguard Premium Wood Sealer

Another highly-rated brand, Rainguard’s premium wood sealer is formulated with water-based silane and siloxane blend. So it leaves an almost invisible finish that does not create a slippery surface like most sealants. This makes it perfect if you want a natural-looking wood surface.

Aside from mold, mildew, water, oil, and gas, it also protects the wood from thaw damage and freezing. So if you live in colder regions, this is the ideal sealer for you.

Pros:

• Natural-looking finish
• Non-toxic
• Includes UV stabilizers
• Protects against mold, mildew, water, oil, and more.

Cons: 

• Cleaner/Prep solution is sold separately
• It may require reapplication after a few years

3. DEFY Crystal Clear Sealer

Composite lumber can be difficult to seal since it’s a mixture of various materials. But no worries. This outdoor wood sealer can protect your composite wood from mold, mildew, and the ever-annoying algae stains. It’s formulated with zinc-nano particles that act as a sunblock for your wood. This not only prevents graying, but it also helps preserve the wood’s natural color for a long time.

Pros: 

• Designed specifically for composite wood
• Protects against mold, mildew, and algae stains
• Preserves natural color

Cons:

• It may appear darker on other wood types
• Requires yearly recoating

4. Anchorseal 2

A combination of plant-based polymers and wax, Anchorseal 2 is specially formulated for exotic hardwoods. However, it is more commonly used to protect the ends of green logs and lumber from checking and splitting. It also has a winter formula that protects the wood from freeze-thaw damage.

Pros: 

• Eco-friendly
• Water-based
• Specially formulated for exotic hardwoods
• Protects against end-checking or drying splits

Cons:

• A bit pricey
• It can slightly darken other wood types

5. Roxil Wood Protection Cream

Like Rainguard, Roxil’s Wood Protection Cream is also formulated with a semi-silicon material. This allows it to penetrate the wood and leave an invisible finish. It also provides an instant waterproofing effect with just one application. Though it can be applied to most types of wood, experts deem it more suitable for softwood timbers.

Pros:

• Suitable for softwood timbers
• Provides instant waterproofing

Cons:

• Thicker consistency
• The lid can be flimsy

6. Eco-Advance Exterior Wood Waterproofer

Just like what its name suggests, this spray-on wood sealer is safe to use around people, plants, and animals. It also has a milder odor than most wood sealers. So it’s safe to walk on even just a couple of hours after application. Since the formula is water-based, it’s non-flammable and can be used even in freezing temperatures.

Pros:

• Safe to use around people, plants, and animals
• It has a milder odor
• It can be used in freezing temperatures.

Cons:

• It may require a sprayer
• You may need 2 or more coatings

7. Ready Seal Stain and Sealer for Wood

Combining wood stain and sealer in one product, Ready Seal is an economical choice since it also needs no primer. Its oil-based formula penetrates into the wood protecting it from water, mold, and mildew. One drawback, however, is that you need to recoat the wood every two years.

Pros:

• Combines wood stain and sealer
• Economical
• Protects against water, mold, and mildew

Cons:

• Requires recoating every two years
• No UV stabilizers

8. Pure Tung Oil Natural Wood Sealer

Since the time of Confucius, tung oil had been used to both preserve and enhance the appearance of wood. It’s all-natural so you don’t have to worry about toxic chemical fumes. When exposed to air, the tung oil dries and creates a transparent film with a deep color. This gives the appearance of a perpetually-wet look. It was commonly applied on boat decks but is now also used in floorings.

Pros:

• All-natural
• No additives
• Versatile
• Enhances appearance with a perpetually wet look

Cons:

• Thick consistency
• It takes longer to dry compared to other sealers.

(Related: The Best Wood Stabilizers That Won’t Break the Bank)

9. Olympic Stain Maximum Waterproofing Sealant

This sealant is designed to provide long-lasting protection for all wood surfaces. It offers advanced weather protection. It guards against water damage, UV rays, and mildew growth. The sealant also enhances the natural beauty of the wood and provides a durable finish.

Pros:

• Durable formula
• Easy clean-up
• Provides advanced weather protection
• Guards against water damage, UV rays, and mildew growth

Cons:

• The cans may come dented
• It might give a darker look to some wood types