Does your beautiful wooden deck look a little sad and weathered after a long summer?
Rain, sun, and even just walking on it slowly damage the wood. You know you need to protect your deck, but choosing the right sealant feels like a huge puzzle. Should you pick an oil-based one or a water-based one? Will it look natural or glossy? Picking the wrong sealant means wasted time and money, and your deck still ends up looking dull.
This guide cuts through the confusion. We will explain what deck sealants actually do and break down the different types so you can choose the perfect shield for your wood. You will learn exactly what to look for before you buy.
Ready to keep your deck looking strong and vibrant for years to come? Let’s dive into everything you need to know about wood deck sealants.
Top Wood Deck Sealant Recommendations
- WATERPROOFING STAIN – Bring out the beauty of your outdoors with Thompson’s WaterSeal Clear Multi-Purpose Waterproof Stain. Proven to waterproof concrete, brick, exterior wood and other exterior surfaces.
- CLEAR STAIN – This outdoor wood stain and sealer provides a clear finish. It will hide the grain, but still allow the texture to show. It provides complete protection while adding enhancing the natural color.
- FADE RESISTANT FINISH – The advanced polymers in this outdoor wood and deck stain deliver fade-resistant color so it stays looking great year-round. The coating resists UV damage, so you can apply with confidence.
- EASY TO USE – Whether you’re refinishing an existing fence or putting the finishing touches on a new patio, this concrete, brick, wood sealer is easy to apply. Clean the surface thoroughly prior to use for best results.
- THOMPSON’S – Protecting & maintaining all your exterior surfaces, can easily be simplified if you know where to start. Thompson’s WaterSeal is here to take the edge off, thanks to our one-coat products, informative how-to guides & decades of expertise.
- Year-Round Protection in Just One Coat
- Helps Prevent Water Damage
- Exceeds Industry Standard ASTM-D4446 for Waterproofing Wood
- Crystal-clear sealer and sunblock protects wood and prevents yellowing
- MARINE SEALANT: Our liquid formula creates a UV-stable coating for protection against the elements, saltwater spray, and water damage. Marine is a great protector for outdoor furniture, thermally modified wood, and boat docks. Marine is safe for use over open water and is non-hazardous to aquatic life.
- DECK STAIN: It's water-based, ultra-low VOC, great for enhancing the extended life of your flooring, siding, and porch. The paint forms a water-resistant shield around wood fibers at the cellular level to help preserve the natural color.
- WATERPROOF WOOD SEALER: The wood used on boat docks, decks, and retaining walls near rivers, lakes, oceans, and ponds is subjected to constant moisture. We crafted a sealer, remove stain, and finish all in one, specifically for these installations.
- WOOD SEALANT: Our fast-drying protector penetrates wood below the surface, coating the wood fibers at the cellular level, which creates a long-lasting, flexible, breathable barrier. It provides a no-fuss, easy clean-up with soap and water.
- SEAL-ONCE: Our user-friendly wood sealers and stains are an effective way to protect your lumber or concrete against water damage. When you use Seal-Once, you have the satisfaction of knowing our products will not harm pets, plants, or people.
- Ready to use clear sealant and waterproofer
- Perfect for new wood, pressure-treated wood, weathered wood and wood with a weathered clear or semi-transparent stain
- Durable sealant that provides waterproofing protection
- Repels water
- Provides SUNBLOCK UV protection
- Ready mix, ready to use semi-transparent wood stain and sealant all-in-one
- Waterproofing deck and fence protection, dries in 24 hours
- Durable water based sealant that provides waterproofing protection with resistant coating
- SUNBLOCK UV defense
- Exclusive SCUFF GUARD Technology
- Ready to use clear wood sealant and waterproofer
- Perfect for new wood, pressure-treated wood, weathered wood and wood with a weathered clear or semi-transparent stain
- Durable water base sealant that provides waterproofing protection; Coverage up to 350 sq. ft. per gallon
- Repels water
- Provides SUNBLOCK UV protection
- WATER-BASED POLYURETHANE WOOD FINISH: Our sealant provides top-notch protection against wear and tear in high traffic areas. It's odorless and ideal for use on wood siding, log homes, swing sets, outdoor furniture, wooden deck and fence, and more.
- WOOD SEALANT: Unlike many sealers that only form a topcoat, our protector penetrates below the surface to create a long-lasting, water-resistant shield around the wood. It helps protect against the elements.
- FLOOR SEALER APPLICATOR: Our premium gloss is ultra-low VOC and great for enhancing the extended life of your exterior flooring. The sealant can be safely applied around your home, landscaping, vegetation, or over any water area.
- WATERPROOF SEALER: Ditch the oil-based sealers and choose a UV-stable coating option. Our fast-drying liquid creates a flexible, breathable barrier and provides a no-fuss, easy clean-up with soap and water, as it allows the wood to grey naturally.
- SEAL-ONCE: Our user-friendly wood sealers and stains are an effective way to protect your lumber or concrete against water damage. When you use Seal-Once, you have the satisfaction of knowing our products will not harm pets, plants, or people.
- Ready-to-Use Formula: Commercial-grade, ready-to-use waterproof wood sealer can be easily applied using a standard garden pump sprayer, eliminating the need for complicated equipment or professional help. Simply spray on for quick and hassle-free application
- Versatile Protection: Perfect for wood decking, fences, plywood, shingles, siding, and more. Dries clear to preserve the natural look of your wood surfaces while providing effective wood preservation
- Comprehensive Defense: Provides robust waterproofing and protection for wood surfaces against water damage, oil, stains, de-icing salts, and pool/spa chemicals. Its advanced siloxane formula penetrates deep into the wood, creating a long-lasting barrier that shields your surfaces from the elements
- Eco-Friendly and Safe: Water-based, non-toxic, non-flammable wood sealant formula that is safe for use around plants, pets, and people. Ensures a safe environment during and after application, making it ideal for family homes and gardens
- Breathable Barrier: Vapor permeable wood sealer waterproof outdoor spray allows new wood to breathe while providing superior waterproofing protection
The Ultimate Buying Guide for Wood Deck Sealant
Protecting your deck keeps it looking great for years. A good wood deck sealant acts like sunscreen for your wood. It stops water from soaking in and prevents sun damage. Choosing the right one can feel tricky. This guide will help you pick the perfect shield for your outdoor space.
Key Features to Look For
When you shop, look closely at the product label. Certain features make a sealant better.
- Water Repellency: This is crucial. A good sealant makes water bead up on the surface, not soak in. Look for “hydrophobic” properties.
- UV Protection: Sunlight breaks down wood fibers, causing graying. Excellent UV blockers keep the wood color rich.
- Mildew and Algae Resistance: Damp areas encourage mold growth. Choose a sealant with built-in mildewcides to keep things clean.
- Penetration Depth: The best sealants soak *into* the wood, not just sit on top. Deeper penetration means longer-lasting protection.
- Durability/Longevity: How long does the protection last? Some last one year; others last three. Check the expected lifespan.
Important Materials in Sealants
Deck sealants generally use two main types of bases. The base material affects how the product performs and how easy it is to use.
Oil-Based Sealants (Alkyd)
Oil-based sealants soak deep into the wood pores. They often provide superior protection against moisture penetration. They usually look richer on the wood grain. However, they take longer to dry and require mineral spirits for cleanup. This characteristic can sometimes lower their quality score for easy use.
Water-Based Sealants (Acrylic/Latex)
Water-based options clean up easily with soap and water. They dry much faster than oil-based types. Modern water-based formulas offer excellent UV protection. They might not penetrate as deeply as oil, but they are very popular because they are user-friendly.
Factors That Improve or Reduce Quality
What makes one can of sealant better than the next? Quality often comes down to solids content and application ease.
Improving Quality
- High Solids Content: Solids are the actual protective ingredients left on the wood after the sealant dries. Higher solids mean thicker, longer-lasting protection.
- Transparency vs. Toner: Clear sealants let the natural wood show through but need more frequent reapplication. Toners (light colors) add extra UV protection, improving longevity.
- Breathability: The wood needs to release trapped moisture. A quality sealant allows moisture vapor to escape, preventing peeling or blistering.
Reducing Quality
- Low Solids Content: Cheap sealants often contain mostly water or solvents that evaporate quickly, leaving little protection behind.
- Film-Forming Tendency: If a sealant creates a thick, plastic-like layer on the surface, it will likely peel or flake off when the wood naturally expands and contracts.
User Experience and Use Cases
Think about your deck and how you use it before you buy.
Application: If you have a very large deck or need to finish quickly, a fast-drying, water-based product might be the best choice. If you have an old, thirsty deck, an oil-based penetrant works wonders. Always apply sealants to clean, dry wood for the best results.
Deck Type: For pressure-treated wood, most sealants work well. For hardwoods like Ipe or Cedar, you need specialized penetrating oils that can handle dense wood fibers. Always check the label for wood type compatibility.
Maintenance: Low-maintenance users benefit from 2-3 year sealants. High-traffic areas might require annual touch-ups, regardless of the product advertised lifespan.
10 Frequently Asked Questions About Deck Sealants
Q: How often should I reseal my deck?
A: Most decks need resealing every one to three years. Check the water test yearly; if water soaks in quickly, it is time to reseal.
Q: Can I apply sealant when it is sunny?
A: No. Direct, hot sunlight makes the sealant dry too fast. This prevents deep penetration. Apply on a cloudy day or when temperatures are mild.
Q: Does sealant change the color of my wood?
A: Yes. Even clear sealants add a slight amber tone. Toners or semi-transparent stains change the color more noticeably but offer better UV protection.
Q: What is the difference between a stain and a sealant?
A: A sealant prioritizes water protection. A stain prioritizes color and UV protection, though most quality sealants offer both.
Q: How long must the wood dry before sealing?
A: If the wood is new pressure-treated lumber, wait several weeks for it to dry out. If you just cleaned the deck, wait until it is completely dry—usually 24 to 48 hours.
Q: Can I use a paint sprayer?
A: Yes, you can spray most modern sealants. However, you must always back-brush immediately after spraying to work the product into the wood grain.
Q: Do I need to strip the old sealant off?
A: If the old sealant is flaking or peeling, yes, stripping is necessary. If the old sealant is intact and the new product is compatible, you can often just clean the deck thoroughly.
Q: Will sealant stop my deck from cracking?
A: Sealant slows down the process by controlling moisture changes, but it cannot stop all cracking caused by wood movement.
Q: Are water-based or oil-based sealants better for the environment?
A: Water-based sealants are generally considered better because they have fewer harsh solvents (VOCs) and clean up easily without harsh chemicals.
Q: What is the “water bead test”?
A: Drip a few drops of water on the deck surface. If the water forms tight little beads, the sealant is still working well. If the water soaks into the wood quickly, resealing is needed.