Wood is a popular and versatile raw material that is used for all types of projects—from furniture to decking to wall panels. However, due to its porosity, wood needs to be adequately protected from wear, water, weather, and pests.
The best way to protect wood is with a water sealer, and the key to selecting the right sealer lies in what type of wood product you’re trying to protect and what you are protecting it from.
Why Use Water Sealer for Wood?
Water sealers are a proactive measure you can take to protect wood from environmental damage and increase durability by creating a protective barrier.
Any wood exposed to outdoor elements needs to be treated to prevent cracking, warping, mold, mildew, scratches, and dirt accumulation, even if it’s covered by a porch or awning.
Many water sealers also protect against fading, sun damage, humidity, frost, and insects.
Types of Water Sealers
There are several types of water sealers, each with its own specific properties and ideal use cases. Which type you choose will depend on the wood product’s level of exposure to the elements, your aesthetic preferences, and maintenance considerations.
Synthetic Sealants
Synthetic sealants include varnish, lacquer, and polyurethane. This type of water sealer soaks into the surface of the wood to strengthen the cellular structure and create a protective barrier against water intrusion and wear.
Best uses for synthetic sealants: Floors, furniture
Natural Oils
Natural oil water sealers include products like linseed oil, tung oil, and teak oil. These penetrative sealers absorb deep into the wood, providing protection against moisture and rot.
Natural oils are designed to maintain the look and feel of natural wood, so there won’t be a glossy surface layer barrier after application.
Best uses for natural oils: Outdoor furniture
Stain Sealers
Stain sealers are efficient multitasking products because they provide both color and protection. Stain sealers are designed to protect from harsh outdoor conditions, so in addition to moisture resistance, many products include additives like UV protectants and mold and mildew blockers.
Best uses for stain sealers: Exterior surfaces
Considerations When Working with Sealant
Following a few best practices can help prolong your sealant’s efficacy, maximizing the look and durability of your wood product.
Prepare the Wood
Before applying any type of water sealer, ensure the wood surface is free of dirt, dust, mold, mildew, and any old finishes. Moisture can prevent adhesion and absorption, so the wood must be completely dry before applying sealer.
Lightly sanding the wood can help the sealer penetrate the surface more effectively and provide a smoother finish.
Choose the Right Sealant
Different woods absorb sealer differently, so choose a product that is suitable for the specific type of wood you are working with.
It’s also important to consider whether the wood product will be used indoors or outdoors. Outdoor sealants need to be more weather resistant than indoor sealers and should offer some level of UV protection.
The final look of the product will also determine the type of water sealer you use. For example, polyurethane will provide a glossy finish, while linseed oil will look more like natural wood, and a stain sealer will let you customize the color.
Apply in Ideal Conditions
Weather conditions and other environmental factors will impact the results you get from your sealer, so it’s important to apply the product in favorable weather or in a climate controlled environment. Extreme temperatures, high humidity, and rain can create cracking, peeling, or weak spots in your protective barrier.
Ideally, when you apply the sealant, the temperature will be 55°F-90°F with a relative humidity level of less than 85 percent.
Understand How to Apply the Product
The application process will vary depending on the type of water sealer and the wood surface you’re applying it to, so it’s important to read the directions for the specific product you’re using.
Be sure to use the appropriate application tools (such as brushes, rollers, or sprayers) depending on the size and type of the wood surface.
Apply the recommended number of coats for the type of wood you are working with (more porous woods may require additional coats) and allow enough drying and curing time between coats to get the desired finish.
Follow Safety Precautions
Misuse of water sealers can result in physical injury. Wear protective clothing, such as gloves, goggles, and a mask or NIOSH-approved respirator to avoid contact with skin and eyes and prevent fume inhalation.
If you are applying the sealer indoors or using an oil- or solvent-based product, be sure your work area is well-ventilated to prevent excessive exposure to potentially harmful fumes.
Don’t Forget Maintenance
To ensure your wood remains protected from water, weather, and pests, conduct periodic inspections to catch early signs of wear or damage. It’s also important to keep wood surfaces clean to prevent degradation of the sealer.
Depending on the local weather conditions, you may need to reapply the sealant fairly regularly to maintain the protective barrier and prevent water intrusion.
Take a Smart Approach to Sealing Solutions
Armed with the right water sealer and the knowledge of how to apply and maintain it, it’s easy to protect the integrity and the aesthetics of your wood products by preventing water intrusion, insect damage, weathering, and fading.
To learn more about wood finishes—and how to pick the best product for your project—download your copy of Why Your Current Wood Finish Brand isn’t Cutting It.
