How to Seal a Deck – In-Depth Guide for Sealing a Deck

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A wooden deck can be a highlight of any home. These are places to really enjoy being outdoors and to make full use of your outside space. The problem with wooden decks is that they require maintenance and some work to keep them looking great. This is because decks are exposed to direct sunlight, rain, temperature changes, and any other direct weather conditions. So, how do you keep your deck in top shape? The best deck sealer will provide a durable, weather-resistant coating to maintain the wood in its best possible shape. Follow our guide below on how to seal a deck for perfect, long-lasting results.



What is a Wood Deck Sealer?

A deck sealer is a transparent coat that you apply over wooden decks to help protect the wood from wear and tear. Deck sealants sit on top of the wood and dry to a clear outer finish. This creates a barrier that protects the wood from things like rain, sunshine, temperature, mold, mildew, and so on. This clear barrier is protective, but it also helps to maintain and enhance the natural grain and look of the wood.

The best deck sealers come in various different forms. This should be chosen depending on the type of wood used, the environmental conditions, and what type of surface you are sealing. Although the best deck sealer provides a high level of protection against things like water, mold, and UV rays, it is still not a complete, permanent solution. The deck will still require regular maintenance, as direct sunlight can still dry out the wood even if it is sealed.



How to Apply a Deck Sealant

Now that you know how to find the best deck sealer, you will need to know how to apply it. Luckily, this is not a very difficult process. You can easily apply the best deck sealant yourself without having to call in a handyman. Just follow this basic step by step process:


Wait for the Right Weather

The first thing to do before applying any deck treatment is to make sure you have the right weather window for the job. Check the forecast to make sure that there is no rain and that the temperature is optimal. You will need at least two days of the rights weather in order to apply the best deck sealer properly and let it cure.

Ideally, the temperatures should be between 50 to 90 degrees Fahrenheit. You don’t want to go through all the work of applying a wood decking sealer, only to have your efforts ruined by bad weather.


Sanding the Deck

Once you have the right weather window, you can get started by preparing the wood for the sealer. Of course, start by removing any furniture or objects on the deck. Then you can start to sand the wood. This is necessary for the sealer to be able to penetrate properly into the wood.

You will need to sand over the entire deck surface to expose all areas of the wood. Any existing paint, varnish, or wood sealer will need to be removed before you can start again with a fresh application. This can be a time-consuming, and exhausting, process. However, it is necessary for achieving great results.

deck sanding


Cleaning the Deck

Once sanded, you need to make sure that the entire deck surface is clean, cleared of any sanding debris, and ready to seal. Wipe away all sanding dust and spray down the deck to get rid of any remaining dirt. You should also put some effort in cleaning between the cracks and gaps of the deck. Then let the deck dry completely before starting to apply the sealer.

Deck Cleaning


Prepare the Sealer

Now the deck is ready and the worst part of the job is behind you. Before starting to apply the sealer, make sure that all of your equipment is ready to go. Give the deck sealant a good stir to make sure that it is consistent and smooth. Shaking the sealer can cause bubbles to form, so remember to stir, not shake! If you are using a paint sprayer to apply the sealer, then you may have to thin the product down a bit to reach the right consistency.

deck sealer reviews


Applying the Wood Deck Sealer

Now it’s time to apply the sealer. This can be done by either brushing it on, using a paint roller, or spraying it on. Brushing is not recommended for decks as the process is time-consuming and you can end up with unwanted brush marks and streaks. We recommend using a paint sprayer or a roller for smoother, faster, and more even results.

Start at the very outer edge and work your way in. Make sure that you don’t end up caught in an island of wet sealer, so always paint in the direction of the door or exit point. Some wood deck sealers may require you to do back-rolling. This is when you use another roller or broom to go over the painted area again to better spread the sealer.

Whether you are applying a clear deck sealer, a stain, or the best deck sealer and stain combo – the process of application will be the same. Once applied, let the first coat dry properly. You can check the guidelines on the product to find the recommended drying time.


Repeat the Application

Once the first coat is applied and dried, it’s time to add a second coat. Simply repeat the application process. This can be done as many times as you need before reaching the right consistency and coat thickness.

Water-based wood sealers often offer thinner coats that dry faster. This means you may need to add more layers to this type of sealer. If you are spraying the sealer on, you may also have to apply additional coats as these layers are usually quite thin.


The Finer Details

The last step is to just make sure that every area, corner, and curve of the deck is covered. You can use a regular paintbrush to go around and get the sealer in between any cracks, gaps, or difficult places that may have been missed. Any exposed area, even if it is small, could let in moisture and end up damaging a larger area of the deck’s finish.

Now you just need to leave the deck to dry fully. This will depend on the type of deck sealer used and the temperature/external conditions. However, it is always a good idea to leave the deck for around 24 – 48 hours after application to make sure that it is completely dried and cured.

clear deck sealer


Why Use a Deck Sealant

Wood is a beautiful material that offers many attractive properties to your home. However, it will eventually start to fade and crack if it is not properly taken care of. The best deck sealant helps to keep the wood in its best condition in order to keep it looking good and maintaining its durability. Some of the reasons to use a deck sealant include:

  • Protecting the wooden deck from mold or mildew
  • Adding a layer of protection against harmful UV rays and direct sunlight
  • To protect the wood against water damage
  • To add a layer of durability for protection against general wear and tear
  • To protect the wood from cracking
  • Deck sealant helps to maintain the natural appearance of the wood

wood deck sealer



Deck Sealer vs Deck Stain

Something that many people get confused by is the difference between the best deck sealer and stain. We have already established the basic qualities of a deck sealer above. The main difference between these is that a deck sealer sits on top of the wood while a stain soaks into the wood. Deck stains provide water-resistant qualities too, but they also have a level of pigment present in the stain. The opacity of stains varies depending on the amount of pigment present. This can be anywhere from semi-transparent to opaque.

One of the main reasons to use a stain is to provide additional protection against UV rays. This is because the stains are darker thanks to their pigment. Basically, the darker the stain, the greater the UV protection. Another benefit is that stains are available in a wide range of colors, so they can help to add different effects to the wood. Wood sealers are transparent and are used to maintain the original quality of the wood.



Water-Based and Oil-Based Deck Sealants

When choosing a deck treatment option, there is one big consideration to make: this is whether you choose water- or oil-based sealer. These two options are both readily available, and they provide quite different results.

Water-based deck sealants are a safer, more eco-friendly option. These substances dont contain harmful chemicals which is something that many people prefer. Being water-based, they are easier to clean up and are very versatile in their use. These sealers also dry much quicker. However, they tend to be less durable and long-lasting when compared to oil-based deck sealers.

An oil-based deck treatment offers a greater level of strength and durability. This is great for decks, as these are areas that experience lots of weather damage. The downside is that oil-based sealers can contain toxic solvents and chemicals. These sealers require careful use during their application, and they are not easy to clean up if messed. They also take a long time to dry and are often more expensive.

wood decking sealer



Important Considerations for Choosing a Deck Sealant

When choosing the best deck sealer for your needs, there are a few important things to take into consideration. Each product is unique, offering a different set of characteristics. Below are some important things to think about when looking for a wood deck sealer.

deck treatment


Clear or Colored

You can get a clear deck sealer or a tinted, pigmented version. Clear deck sealers are great for enhancing and showing off the natural grain of the wood. These types of sealers offer an attractive coat to allow the wood to maintain its original beauty. Clear deck sealers are common options, but they do have one disadvantage: they offer less UV protection than stains.

If you are looking for the best deck sealer and stain combination, then you will notice the product will be colored. This tint offers a greater level of UV resistance, and it needs to be matched to the wood you are using. The downside is that many people don’t want to alter the coloring of the original wood.



One of the most important aspects of any wood decking sealer is durability and weather resistance. A clear deck sealer is not just there to keep the wood looking good, but it is also there to protect it from the elements. UV protection, resistance against cracking, temperature fluctuations, water, oil, mold, mildew, and all sorts of other forces should be present. Out of our deck sealer reviews, all of the products are made for tough exterior use and provide a great level of protection.

wooden deck sealing


Ease of Application

How easy is the wood sealer to apply, and does it match your preferred application method? Different wood sealers come in varying levels of thickness which changes the application process. They also have different drying times. If you plan on spraying the sealant, then be sure to get a product that is thin enough for your sprayer.

Oil-based sealers are often more difficult to apply as they can form bubbles on the surface. This is not something that happens with water-based options. If you are a beginner, then a water-based sealer is recommended.


Environmental Friendliness

Environmental concerns are always an important aspect when choosing the best deck sealer. This includes the question of how many volatile organic compounds (VOCs) the sealer contains. In some places, there are strict regulations on VOCs. Water-based products have a much lower VOC content – if any at all. This also affects the amount of fumes that the deck sealer releases. The best products should be safe for the environment, as well as be safe to work with.

Choosing the Best Deck Sealer



When you apply the deck sealer, it can make quite a mess. How easily the substance is to clean up can actually make a huge difference on the overall project. Oil-based sealers will require some type of solvent to clean it up – such as acetone or paint thinner. Water-based products should be easily cleaned up with water and regular soap.


Drying Time

Some oil-based wood sealers may take up to two full days to dry properly. If a sudden rainstorm appears, this is not ideal. Always consider the drying time of the product and plan your project accordingly. Typically, water-based sealers dry much faster.


Maintenance and Preparation

Can you simply apply the sealer to your deck, or do you need to spend hours preparing the deck first? This is an important point in terms of maintenance too. SOme deck sealers require you to strap down the deck and start from bare wood, while others allow you to paint over existing sealers. Oil-based sealers are usually tougher here and require less preparation work before applying them.

deck sealant



Frequently Asked Questions


What is the Best Deck Sealer for Pressure Treated Wood?

The best deck sealer for pressure-treated wood would either be a penetrating sealer and stain combination, or a deck water sealer. You get specialized products made specifically for decks that work perfectly for pressure-treated wood.


How Long to Dry Deck Sealer?

This depends on the type of sealer used, the weather conditions, and how thickly the sealer is applied. Some sealers can take a few hours to dry while others can take two days. Generally speaking, it’s best to leave the deck for 24 hours to let the sealer dry before walking over it.


How Often Do You Need to Apply Deck Sealer?

While this varies depending on the climate and the type of sealer you have used, the general lifespan is about three years before you have to reapply a new layer of deck sealer.


What is the Best Application Method for Deck Sealer?

Deck sealer can be applied with either a sprayer, a roller, or a brush. Sprayers help to achieve a more even, speedy finish. Rollers also achieve an even finish and are pretty easy to use. Using a natural bristle brush will take more effort, but it does allow you to get the sealer into any cracks or gaps easier.


Is it Better to Stain or Seal a Deck?

Using the best deck sealer and stain together is often the best choice. Stains provide greater UV protection, while sealants provide greater protection against weather and water damage. Using a combination offers a more well-rounded protective coat.


Keeping your deck protected is easy to do with the best deck sealer. Deck sealant is necessary for providing protection against water and weather in order to keep the wood looking great. Follow our deck sealer reviews and top product picks above, and you will end up with a fantastic finish over your beloved deck. We hope your project is a success!