Does your beautiful wooden deck or fence look dull and weathered after just one summer? You spend time and money on your outdoor wood, but the sun and rain take their toll quickly. It’s frustrating to see your hard work fade and splinter right before your eyes.
Choosing the right exterior wood sealer feels like a confusing puzzle. Should you pick oil-based or water-based? Do you need UV protection or just water resistance? The wrong sealer means wasted money and wood that still gets damaged. Nobody wants to reapply a product every few months just to keep things looking good.
This guide cuts through the confusion. We will break down exactly what makes a great wood sealer. You will learn the differences between top products so you can protect your investment and keep your wood looking fantastic for years. Get ready to choose the perfect shield for your outdoor wood!
Top Exterior Wood Sealer 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
- 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
- Durable, poly for outdoor wood surfaces such as furniture, doors, windows, fences, trim and more
- water based formula is easy to apply and cleans up with soap and water
- Dries to the touch in 30 minutes and covers up to 87 sq. ft. per quart, recoat after 2 hours
- supports the Weather and UV , top coat does not yellow and helps against natural elements
- Crystal clear, satin finish provides a classic and natural look
- Requires no primer. Ready Seal is darkest when first applied. It reaches its true color in approximately 14 days. Do not apply Ready Seal over painted or newly stained surfaces. Sealed surfaces inhibit penetration.
- May be applied using sprayer, roller or brush onto the woods surface.
- Requires no back brushing and will never leave runs, laps, or streaks.
- Requires no wet-line application, the product will blend itself and can be applied in any temperature range for proper application.
- "Goof Proof" application
- 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 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
- PROTECTIVE CLEAR FINISH – Minwax Helmsman Water Based Spar Urethane is a crystal clear wood finish that is specially formulated to protect against nature’s toughest conditions.
- EFFECTIVE YEAR ROUND – This wood varnish forms a protective barrier against rain and moisture to protect your projects and keep them looking their best. Special oils allow the finish to expand & contract with the wood as seasons and temperatures change.
- VERSATILE – Ideal for use on doors, windows, trim, bathroom cabinets, bar tops, kitchen countertops, outdoor furniture and more. It’s a versatile water-based spar urethane that dries quickly and cleans up easily with warm water.
- GLOSS FINISH – Give your wood projects a sleek finish with this gloss clear varnish. It not only protects the natural beauty of the wood, but offers a shiny, sleek sheen for a modern look. It’s ideal for use over light colored woods and stains.
- A BRAND YOU CAN TRUST – Minwax is America’s leading brand of wood finishing and wood care products. Since 1904, we have been inspiring consumers to Keep on Finishing. We offer consumers a complete line of products to meet every wood finishing need.
The Ultimate Buying Guide for Exterior Wood Sealer
Protecting your outdoor wood is important. Decks, fences, and patio furniture face sun, rain, and snow. A good exterior wood sealer keeps them looking great and lasting longer. This guide helps you choose the best sealer for your project.
Key Features to Look For
When shopping, focus on these important features. They tell you how well the sealer will work.
1. Water Resistance and Repellency
The sealer must keep water out. Water causes wood to rot and crack. Look for labels that promise excellent water beading. This means water rolls right off the surface.
2. UV Protection (Sun Blocking)
Sunlight breaks down wood fibers. This causes graying. A quality sealer includes UV inhibitors. These act like sunscreen for your wood, keeping the color rich.
3. Mildew and Mold Resistance
Damp wood often grows mold or mildew. Choose a sealer with built-in mildewcides. This prevents ugly black or green spots from growing on your wood.
4. Penetration Depth
A great sealer soaks deeply into the wood grain. Deep penetration offers long-lasting protection. Surface-level sealers wear off quickly.
Important Materials in Wood Sealers
Wood sealers generally come in two main types based on their ingredients.
Oil-Based Sealers
- Pros: Oil-based sealers soak in very well. They often offer deeper protection and look richer on the wood.
- Cons: They clean up with mineral spirits (a strong solvent). They also take longer to dry and release stronger fumes.
Water-Based (Acrylic/Latex) Sealers
- Pros: These are easy to use. You clean brushes and spills with just soap and water. They dry fast and have low odor.
- Cons: They might not penetrate as deeply as oil-based options, though modern formulas are very good.
Factors That Improve or Reduce Quality
The final look and lifespan of your sealed wood depend on several factors.
Factors That Improve Quality
- Solid Content: Higher solid content means more protective material is left on the wood after drying. Higher is usually better.
- Breathability: The sealer must let moisture vapor escape from inside the wood. If the wood cannot breathe, trapped moisture causes peeling.
Factors That Reduce Quality
- Improper Preparation: Applying sealer to dirty or wet wood severely reduces quality. The sealer will not stick well.
- Thin Coats: Applying one very thin coat is not as effective as two medium coats. Thin coats wear out fast.
User Experience and Use Cases
Think about where you will use the sealer. This guides your choice.
High-Traffic Areas (Decks, Walkways)
These areas need tough protection. You need a high-solids, durable formula. You might need to reapply every 1-2 years.
Low-Traffic Areas (Siding, Gazebos)
These areas need good UV and water protection but face less wear. A standard water-based sealer often works perfectly here and lasts longer.
Application Ease
If you are a beginner, water-based sealers offer a much friendlier experience. They are easier to spread evenly and dry faster, allowing you to finish the job sooner.
10 Frequently Asked Questions (FAQ) About Exterior Wood Sealer
Q: How often should I reapply the sealer?
A: Most high-quality sealers last between two to three years on decks. Vertical surfaces like fences might last four years or more. Always watch for water stopping beading up; that means it’s time to reseal.
Q: Can I apply sealer when it is hot outside?
A: Avoid applying sealer when the wood surface is very hot (over 90°F). The sealer dries too fast, preventing it from soaking in properly, which causes a poor finish.
Q: Does sealer change the color of my wood?
A: Many sealers are clear and offer a natural look. However, many also come in tints (like cedar or walnut). Always test a small, hidden area first to check the final color.
Q: What is the difference between a stain and a sealer?
A: Stains primarily add color, though many good stains include sealer ingredients. A dedicated sealer focuses purely on protection from water and sun. Many products combine both functions.
Q: Can I apply sealer over old paint?
A: No. You must remove the old paint completely first. Sealers need direct contact with bare wood to soak in and protect the surface.
Q: How long does wood sealer need to dry before rain?
A: Water-based formulas usually need 2–4 hours before light rain. Oil-based sealers often require 12–24 hours for full protection against rain. Check the can’s instructions carefully.
Q: What is the best way to clean wood before sealing?
A: First, sweep away all dirt and debris. Next, use a dedicated wood cleaner or deck wash. Scrub gently with a stiff brush. Rinse thoroughly and let the wood dry completely (usually 2–3 sunny days).
Q: Can I use an interior sealer outside?
A: Never use interior sealers outside. Interior products lack the tough UV blockers and mildewcides needed to fight harsh outdoor weather.
Q: Does sealer protect against termites?
A: Standard wood sealers offer moisture protection, which indirectly discourages some pests. However, specific termiticides must be used for true termite defense; sealers alone do not stop termites.
Q: Which is better for decks: oil or water-based?
A: For decks that get heavy foot traffic, oil-based sealers historically provided superior penetration. Modern, high-quality acrylic (water-based) sealers now offer comparable durability with easier cleanup.