You’ve probably got a lot of things on your to-do list this time of year. There are tasks to do outside — parties to host, gardens to tend to — the usual stuff. But don’t put off sealing your deck.
Why?
It’s going to keep your deck in good shape. Your deck will tank your curb appeal if you keep putting it off. You start inviting too much moisture to the party, and the wood is going to weather quickly.
Applying a sealant today keeps the moisture away (remember that). I’m going to briefly share why sealants are important and what you can expect when shopping around. Then, I’ll share four of my favorite deck sealers of 2025.
Why Is Using a Deck Sealer Important?
A deck sealer is a transparent protective layer that maintains your wood’s natural look and helps keep moisture away. It’s your first line of defense against mold, mildew, and rot.
The protection provided by this layer is crucial for wood surfaces in areas with high humidity or frequent rainfall because unsealed wood degrades pretty quickly — and our weather definitely puts deck to the test.
A USGS study noted that Long Island gets between 40 and 50 inches of precipitation yearly (depending on where you are). That’s a good amount of water. It comes in rain, sleet, and snow, and it will all break down your wood deck.
Sealers perform exceptionally well in keeping moisture out. But how do they differ from deck stains?
While sealers and stains are moisture barriers for wood surfaces, not all protect well against the sun. Stains do. They also provide many color options.
Paired with a good stain, the following sealers will keep your wood deck in good shape.
Varathane Urethane Ultimate Sealer
People who need durable protection combined with a strong finish will find a product like Varathane 9441 Oil-Based Spar Urethane helpful. It creates a durable glossy surface that provides strong resistance to all weather conditions, including heavy rain and sun. It’s one of the more multipurpose sealants I have on this list.
It stands out because UV absorbers help minimize sun damage while preventing fading and discoloration. The oil-based formula brings out wood grain, creating rich, warm tones that become deeper with time. Even though its drying time is longer and requires a bit more cleanup, it’s hard not to have on the list.
Thompson’s WaterSeal
Long Island homeowners also ask me about Thompson’s WaterSeal (which is why I wrote an entire post on it).
It’s popular because budget-minded homeowners find its straightforward moisture protection affordable and reliable. Apply once and you’re good to go. This sealer penetrates deeply to form a protective water-repellent barrier against rain, snow, and humidity damage.
The clear formula helps preserve the original appearance of the deck. It doesn’t offer great UV protection, though. People who wish to protect their surfaces from sun damage should opt for tinted formulas because they deliver both color enhancement and superior sun protection.
Thompson’s WaterSeal works on wet and dry wood surfaces, which reduces preparation time and offers more scheduling flexibility for outdoor work that needs favorable weather conditions.
Eco Advance Exterior Wood Waterproofer
Most people choose Eco Advance Exterior Wood Waterproofer because it’s non-toxic. I’d always use caution when products claim they’re pet-safe and family-safe. But the Eco Advance lines do meet volatile organic compound (VOC) standards and are generally considered to be safe.
This sealer provides good water protection and helps maintain the original appearance and texture of the decking.
Like some of the others, Eco Advance’s sealer lacks significant UV protection but works effectively with tinted finishes and allows for frequent reapplications because it dries quickly and cleans easily.
Wolman Raincoat Clear Water Repellent
Need a quick-drying sealer? Wolman Raincoat Clear Water Repellent is a good option. The water-based formula works well on damp wood surfaces, which makes it perfect for limited timeframes and spontaneous weekend jobs. The finish stays clear and non-film-forming to preserve wood’s natural grain and tone while subtly protecting the deck.
Raincoat functions as a hydrophobic barrier designed mainly to protect wood from rain and snow, as well as daily moisture exposure. The product offers limited UV protection but works well for shaded decks.
You can apply it by spraying, rolling, or brushing, and cleaning after application requires nothing more than soap and water.
Olympic Maximum Oil-Based Clear Waterproofing Sealant
Those who swear by oil-based finishes love Olympic Maximum. It’s known for its strength and durability. This treatment penetrates wood fibers to shield them from moisture penetration and adds a soft, warm glow that enhances the deck’s natural grain patterns.
The oil base works perfectly with older or weathered wood because it revitalizes dried boards while preventing cracks and splits from forming over time. Olympic’s clear sealer formula provides moderate UV protection, which helps safeguard exposed decks by preserving their appearance and extending their lifespan.
The product applies smoothly with minimal issues but requires more time to dry.
Quick Summary
Bottom line: you’ve got to use a deck sealer. Don’t put it off. Your wood deck needs to fight back against moisture, and a good sealer is its best hope. I’ve shared five of my favorites with you, but there are a ton out there.
Later, I may get into the details of how sealers work and how to apply them, as well as deck stains. But for now, just know that your deck will be in much better shape if you don’t skip out on this maintenance step.
