Loading

As an Amazon Associate, Decks.com earns from qualifying purchases from the links in this post.

How to Seal Your Deck & Best Deck Sealers

Without a protective coating, exposure to extreme heat and cold can have a detrimental effect on the surface of your wooden deck. And while both sealing and staining serve the purpose of preserving and protecting your deck, sealing in particular offers some very specific benefits.

Deck Sealer

Deck sealer is typically a transparent coat that seeps deep into the wood and forms a clear film on the surface while maintaining the wood’s natural finish. By penetrating the wood, the sealer creates a protective layer that helps minimize water infiltration and lock out moisture. This preventative finish is crucial in reducing fungal growth and wood rot, both of which can shorten your deck’s lifespan. While deck sealer slows the effects of water damage, it does not protect well against harsh UV rays. Even with sealer, direct sunlight will eventually dry up the wood’s natural oils, cause fading and lead to cracking and splitting.

Deck Stain

Deck stain also provides water-resistant qualities, but also adds pigment to the wood in varying opacities, from semi-transparent to solid. Many stains come in a wide variety of tones to choose from, as well, allowing you to achieve a variety of finished colors. Because stains add pigment, they are better suited to block UV light and offer more protection than just a sealer. In fact, the darker the stain, the more pigment that is added, ultimately giving your deck more protection.

Applying Deck Sealer to a Wood Deck

To get the most effective seal possible, thoroughly clean your deck before applying the sealer. Be sure all debris, dust, grime and mildew is removed. Check out our step-by-step guide for the best ways to clean a deck or pressure wash a deck.

Before we get into the step-by-step details of how to seal a wood deck, there are a few things to keep in mind. For starters, don’t apply deck sealer in direct sunlight as the finish will dry too quickly. The sealer needs time to adequately absorb into the wood. Also, if you have a brand-new deck made with treated wood, it’s best to hold off a few weeks to allow the wood to completely dry so the stain is more fully absorbed. Now, you’re ready to begin!

Step 1: Check the forecast

The first step in applying deck sealer is to ensure that you’ve got at least two days of dry weather with temperatures between 50-90 °F. This will ensure the best seal.

Step 2: Clear the deck

It probably goes without saying, but you don’t want to start sealing your deck with furniture, plants and other furnishings scattered about.

Step 3: Sand (if needed)

Before sealing, you may need to sand your deck to ensure that the sealer penetrates the wood adequately. Sanding is time consuming but necessary in many cases. Grab a pole or palm sander to speed up the process, making sure you sand in the direction of the grain. Always wear a safety mask when sanding to avoid inhaling sawdust.

Step 4: Remove debris

After sanding, you’ll want to ensure that the entire deck is free of loose debris. That includes cleaning between the cracks and then making sure the deck is totally dry.

Step 5: Stir sealer

Before applying the sealer, make sure to stir it. DO NOT shake. Shaking may cause bubbles to form in the finish.

Step 6: Apply sealer

Using a brush, paint roller, or sprayer, apply a thin coat over a two-to-three-board section. You can always add another thin coat later as it will apply and dry better than one thick coat.

Back-rolling may also be necessary to create the best coat possible. This requires one person to apply the seal and another person to use a roller or broom to spread puddles and work the finish thoroughly into the wood.

Step 7: Repeat & fine tune

Repeat Step 6 for the entire deck. Use a finer paintbrush to apply the sealer in difficult areas, such as cracks, railings and steps.

Step 8: Let it dry

Allow the deck to dry completely before use.

Best Deck Sealers

Protecting your deck is a lot less expensive than building a new one, so don’t leave it exposed to the elements, which eventually leads to wear, rot and mildew. Take action early and often with quality deck stain and sealers to prolong your deck’s longevity.

But how do you know which are the best deck stains and sealers? Which ones can be trusted to withstand weather, wear and tear? Here are some of the best deck sealers on the market:

Thompsons Waterseal Advanced Natural Wood Protector

As one of the best water seal products available, Thompsons will go a long way to preserving your deck from mildew and water damage. It will also help with UV damage and color fading over the long term.

ECO-SAFE Wood Treatment – Stain & Preservation by Tall Earth

One of the great things about Tall Earth’s ECO-SAFE Wood Treatment is that it’s ready to use without any special pre-application prepping, as long as your deck is clean. One application is all that’s needed for protection; no need to apply multiple coats.

Rust-Oleum Coppercoat Wood Preservative

This EPA-registered deck sealer delivers all the benefits of a good sealer while also protecting your deck from termites and ants. You may notice a slight transparent green layer after application but it will fade with time.

CabotStain Australian Timber Oil Penetrating Oil

CabotStain is a high-quality sealer that will penetrate deep into even the densest types of wood, and unlike most other sealers, it can help prevent UV damage with iron oxide pigmentation.

Thompsons Waterseal – Transparent Stain

The best of both worlds, this deck stain and sealer combo provides a transparent color while creating a waterproof surface to prevent damage from mildew, rot and mold. It’s a user-friendly sealer that dries quickly after application.

This page contains affiliate links. If you choose to purchase after clicking a link, Decks.com may receive a commission at no extra cost to you.


Popular Care Articles
Deck Cleaning

Cleaning A Deck

Follow our step by step instructions for how to clean a deck.

Deck Cleaning

How to Clean Outdoor Patio Cushions

Keeping your outdoor furniture cushions clean helps extend their life and makes your deck or patio area look nice. Learn how to clean outdoor cushions.

Deck Cleaning

How to Ink Stamps from Pressure Treated Lumber

Ink stamps seen on pressure treated wood represents where the lumber came from and its grade. Learn a few tricks to remove this ink from your wood at Decks.com.

Next Step: Materials Articles
Composite Decking

Capped Composite Decking

What is capped composite decking? It's a great option if you like the look of wood but not the maintenance. Learn about capped composite at Decks.com.

Decking Reviews

TimberTech

TimberTech Decking is manufactured by Timbertech Limited in Wilmington, OH.

Composite Decking

Eco Friendly Composite & Wood Decking Options

Looking for the most environmentally friendly way to add a gorgeous deck to your home? Learn how composite decking is made from recycled materials at Decks.com.

Get more helpful resources delivered right to your inbox

Explore Articles by Topic

Popular Care Articles
Repairs

How to Remove Scuffs and Scratches from Composite Decking

Removing scuffs and scratches can help make your composite deck look like new. Learn how to fix and prevent your composite deck from future scratches.

Deck Cleaning

How to Pressure Wash a Deck

Pressure washing your deck is the best way to keep your investment looking like new. Learn how to properly clean your wood deck with these tips from Decks.com.

Repairs

How to Restore & Refinish a Deck

Decks need maintenance. A twice-yearly cleaning is needed at a minimum. But wood decks—even with good upkeep—can still warp, rot, or get termites. Plus, no stain or paint job lasts forever. Fortunately, you can reset the clock by restoring your deck and refinishing it.

Next Step: Materials Articles
Decking Reviews

Fence Post Spacing: How Far Apart Should Fence Posts Be?

Spending a little more time and effort up front on determining the best fence post spacing for your deck project, could save you a bunch of time and money when it comes time to build it. Here’s how to do it…

Composite Decking

Comparing Trex Decking Lines: Signature vs Lineage vs Transcend vs Select vs Enhance

Discover the four main types of Trex decking: Transcend Lineage, Transcend, Select, and Enhance. Check out our review to learn what sets each apart.

Decking Reviews

Gorilla Deck

Gorilla Deck Vinyl Decking is manufactured by Homeland Vinyl Products in Birmingham, AL.

Get more helpful resources delivered right to your inbox

Explore Articles by Topic