Everybody wants to extend the life of their deck. Sealing the deck is one step in the right direction. Many turn to Thompson’s Water Seal to complete the job.

We all know wood has a vice. It can’t resist water. It just can’t. Try as we may, wood will do all it can to get a hold of water.

Over time, it’s going to give in to all the rain, snow, and humidity. It will eventually swell and crack, which leads to decay. Sunlight compounds the issue by breaking down the wood fibers, resulting in fading.

A high-quality seal, like Thompson’s Water Seal, is the anecdote. Why this product in particular? Well, whenever I talk to Long Island homeowners thinking about taking on the job themselves, they mention Thompson’s Water Seal. I have no preference and no affiliation with them. I’d prefer a more professional sealant. This product is hotly debated on its effectiveness. But still, plenty love it for its affordability. Do your due diligence. I know, though, that this is one I hear about often. So, rather than give you a generic application tutorial, I’ll use Thompson Water Seal as a guide (the process is mostly the same for other sealants).

Why Long Island Homeowners Love Thompson’s Water Seal

Thompson’s Water Seal is one of the top solutions for homeowners requiring dependable wood protection. The sealant enters the wood structure to form a protective shield against moisture while stopping water from getting in. This guide will show you how to apply the product correctly to achieve maximum durability.

Thompson’s Water Seal stands out because you really only need one coat in most cases. It offers decent protection from the weather. Your wood will last much longer because the formula in sealant repels water and UV rays. It comes in both transparent and colored versions. Many homeowners I talk to about this stuff like the transparent version because it protects the wood without changing its look.

Thompson’s Water Seal works on fences, furniture, and other wood items.

How To Apply Thompson’s Water Seal

Step 1: Preparing the Wood for Sealing

Getting the wood ready serves as the foundation of a successful application. Neglecting this step is a bad idea. If you don’t, you could negatively affect the seal — best to take the time and do it right. Thompson’s WaterSeal requires wood surfaces to be thoroughly cleaned and completely dry without any existing protective coatings before application.

Wood can have a lot of things on its surface that mess with the sealant. Some believe in mill glaze, a varnish-like glaze that allegedly happens in the milling or planing process. Others call it a myth. Either way, wood needs to be cleaned before using Thompson’s Water Seal.

To prepare the wood surface properly, remove any imperfections through a light sanding process or application of a wood cleaner. You’ve got to get rid of dirt, mildew deposits, and previous sealing layers.

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Begin by clearing debris and cleaning the surface by spraying it with a hose. You should use a wood cleaner or mix warm water with mild detergent. Pressure washers work well for tough stains, but I’d always use them with caution. Use a setting that’s lighter than normal to make sure you’re not taking huge chunks out. I’d just stick with a bristle brush.

After cleaning the wood, make sure it dries completely. If the wood is wet, it becomes difficult for Thompson’s Water Seal to absorb evenly, resulting in a patchy finish. To achieve optimal results, allow the surface to dry completely for 24 to 48 hours before applying the sealer.

Step 2: Applying Thompson’s Water Seal

Before you do anything, check the weather. Somewhere between 50°F and 90°F is best. Don’t apply if any amount of rain is forecasted within 24 hours. Direct sunlight can heat the surface too much and cause the sealer to dry rapidly, which results in an uneven finish.

You should stir the product thoroughly but avoid shaking it to get a consistent result. When you shake the product, air bubbles develop, which causes an uneven appearance.

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Using a brush gives the greatest control during application because it allows the sealer to penetrate deeply into the wood grain.

A roller is faster but more difficult. You may need to back-brush for thorough absorption. A pump sprayer also allows for rapid application but requires finishing with a brush or roller to achieve uniform coverage.

When finishing most projects, a roller should be used on broad surfaces, and a brush should handle edges and detailed areas.

Begin sealing the wood by covering small sections at a time while following its natural grain pattern. Apply the sealer in multiple thin layers, but avoid saturating the surface. Remove any pooled sealer from the wood surface with a clean rag to avoid a sticky residue.

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Most of the homeowners I’ve talked to named price and only needing one application as their top reason for choosing Thompson’s Water Seal. You should wait until the first coat fully dries before adding another layer for extra protection if you do end up needing another pass.

Don’t let anyone access the deck while it’s drying. (This typically only takes a few hours). You can get on it then, but keep foot traffic to a minimum for the next couple of days.

Step 3: Maintaining Your Sealed Wood

Wood deck and fence surfaces need regular maintenance after sealing them with Thompson’s Water Seal to maintain their optimal appearance. Weather conditions, foot traffic, and wood type determine how often you need to reapply wood sealer.

Every year, you should check to see if your wood is still repelling water. Sprinkle some water on the wood surface to check that the sealant works if the water forms beads and rolls off. When water absorption occurs into the wood, you must apply the protective sealant again.

Consistent cleaning helps to prolong the durability of sealed wood. To preserve the protective barrier from all the dirt and mold, you should clean the buildup with either a gentle detergent or a wood-specific cleaner. Never use aggressive chemicals or high-pressure washing techniques because they can remove the protective sealer.

Maintaining your deck, fence, or furniture through regular application of Thompson’s Water Seal keeps them protected and beautiful for years.

Quick Summary

The most straightforward and effective protection for outdoor wood surfaces from environmental damage involves using a sealant like Thompson’s Water Seal. Through proper preparation followed by careful application and continuous maintenance, your deck or fence can resist damage from rain, snow, and sun exposure.

Through the application of Thompson’s Water Seal, you will prolong your wood’s durability and improve its visual appearance. Following these steps will lead to long-lasting protection for new and older structures while reducing future repair needs.