Pressure-treated wood has undergone chemical infusion that imbibes the wood pores with a rot and insect repellant characteristic. The process involves placing wood planks in a depressurized holding tank and removing all the air, then chemical preservatives are infused into the tank, and the wood sucks up these chemicals to replace the air vacuum.
This treatment is great for protecting against rot, mildew, insects and such, but does not seal the wood and does not protect it from natural weather conditions.
List of Top-Rated Deck sealers for pressure treated wood Comparison Table:
The chemicals used in the process included for many years chromate copper arsenic (CCA) which is extremely toxic. The EPA stepped in, and since 2003 the lumber industry prohibits the use of this chemical for protection, preferring organic penetrating oil alternatives. These penetrating oils need to be redone every few years. Just for your knowledge and peace of mind, all CCA infused decks before 2003 are perfectly safe for use, but do require periodic sealing treatment to maintain a shield between the arsenic and human touch.
SealingSealing wood is not a recommendation, it is a must. It is a must because if you don't seal the wood, you will expose it to weather conditions that will penetrate the wood and lead to corrosion from constant water abuse. Also, sealants prevent the wood from drying too fast that usually leads to warping. As such, when buying a sealant for pressure treated wood, consider the color issues too and buy a combo sealant with stain to maintain the color conditions and natural appeal of the wood.
The Best Deck sealers for pressure treated wood Reviews
This is the Ready Seal 515 5-Gallon Pail Pecan Exterior Wood Stain and Sealer
Performance
This ready seal product is a stain and sealant in one. The color of this make is pecan, but there are many more colors to choose from.
This make comes in a 5-gallon container and is ready for immediate application.
Before you apply this product, clean the wood surface from all mildew, dust, dirt, oil, and grease. Other stains can be removed by stripping and allow the wood to dry for 48-72 hours before application. Before applying, make sure all the vegetation nearby is protected against spattering. Take note that the stain is darker when wet and lightens when it dries.
Features
- Contains no linseed oil and will not stain hands.
- Biodegradable when in contact with soil and water.
- Meet current VOC level requirements throughout the United States
Recommendations
This is a classic stain and sealer that requires no massive stepwise preparations, just apply it in two coats, and you can even mix colors to make an exact match.
This is Thompsons Water Seal A21741 1-Gallon Rustic Red Advanced Tinted Wood Protector
Performance
The Thompson's A21741 is a rustic red color stain and sealant. It covers 150-400 Sq. Ft/Gal. and is very easy to apply.
You apply this to a clean and dry surface, which means you need to clean the surface throughly before application, and also wait for at least 24 to 48 hours for the wood to dry. After which, do not mix this product with any others, don't add thinners and shake the canister well to make sure it is completely mixed for application.
The application is straightforward, just apply one coat, if you want a deeper color, then add a second coat. Take note that drying varies on temperature and humidity.
Features
- Prevents Water Damage
- Provides Fade and Scuff Resistant Color
- Coating Resists Mildew and UV Damage
- Adds Color While Showing Some Wood Grain
- Covers 150-400 Sq. Ft/Gal.
Recommendations
Thompson's is a great sealant that comes with a few color variations. This variant is deeply tinted, so you don't really need to apply more than one coat.
This is Thompson's Waterseal 041851-16 Transparent Stain, Cedar
Performance
The Thompsons Waterseal 041851-16 comes with a natural cedar stain and is made using an advanced anti-fading polymer. This brand comes with UV protection as well as exceptional lifetime performance.
This is one of the few makes that can be applied to damp wood, as such, all you need to do is make sure the wood surface is completely cleaned and ready for application.
You should perform a water test on the wood before using this product, if the water beads on the wood surface you don't need to apply a sealant, however, if it is absorbed you do.
Consider sanding and smoothing any old painted surfaces before use. You only need one coat of this product and drying time varies according to the dampness of the wood and the weather conditions.
Features
- Prevents Water Damage
- Advanced Polymers Provide Fade Resistant Color
- Coating Resists Mildew and UV Damage
- Applies to Freshly Cleaned Damp or Dry Wood
- Exceeds Industry Standard ASTM D-4446 for Waterproofing Wood
Recommendations
A great synthetic formulation that can be applied even on damp wood, making this an all year applicable product, even for cold northern territories.
This is Ready Seal 505 5-Gallon Pail Light Oak Exterior Wood Stain and Sealer
Performance
The Ready Seal 505 product is another variant of the 515 stains and sealant in one. The color of this make is light oak, but there are many more colors to choose from.
This make comes in a 5-gallon container and is ready for immediate application.
Before you apply this product, clean the wood surface from all mildew, dust, dirt, oil, and grease. Other stains can be removed by stripping and allow the wood to dry for 48-72 hours before application. Before applying, make sure all the vegetation nearby is protected against spattering. Take note that the stain is darker when wet and lightens when it dries.
Features
- Contains no linseed oil and will not stain hands.
- Biodegradable when in contact with soil and water.
- Meet current VOC level requirements throughout the United States
Recommendations
This is another variant of the Ready Seal classic stain and sealer that requires no massive stepwise preparations, just apply it in two coats, and you can even mix colors to make an exact match.
This is Rainguard 1 Gal Homeowner Wet Look High Gloss Masonry & Wood Acrylic Sealer
Performance
This wood sealant uses a Silane-Siloxane Waterproof Coating that protects your deck from water for up to five years. The proprietary blend of Silanes and Siloxane are mixed together in what they call Micro-Lok™. This makes sure that the mechanical bond of the chemicals to the wood retains its integrity under UV light, freezing to very hot temperatures and under extreme rain and wind conditions.
This product covers more than decks, and you can cover 150-200 square feet per gallon for horizontal applications and Approx. 125-150 square feet per gallon for vertical applications.
Features
- Penetrates deep
- Prevents the growth of mold and mildew
- Stain resistant to oil, gas, and anti-freeze
- Great winterizing agent
- Easy to apply in two coats
- Apply in cold weather down to 40°F
- Easy to clean after application; rinse with soap and water
- Low VOC and low odor
Recommendations
This is a very popular sealant used by many architects around the US, it's an exceptional formulation and will last for five years before the next application.
How to Seal Pressure Treated Wood Decks
Before you decide to seal wood you need to perform certain maintenance jobs to make it ready for sealing, after all, if you are already troubling yourself to make the deck waterproof, it's time to revitalize the wood before sealing.
Start off by cleaning the deck thoroughly, remove all easy to remove stains first. Then apply sanders to scrape off any deeper stains, and smooth the area off with fine polishing cloth.
Consider inviting a professional pressure treatment clean that cleans the wood at 1500-2500 psi, this will assure you clean out all the gunk and particulates from deep pores, and when the wood dries, it is ready to suck up the sealant in place.
Once the wood is clean and the surface is ready for application, let the wood stand for at least 2 days in hot, dry weather (preferably) and allow the wood to dry inside as well as on the surface. There are a few exceptions to dry wood application, as mentioned above, Thompsons Water Seal Advanced Wood Protectors can be applied to damp wood too.
Once you have allowed the wood to dry, choose the stain, it can be transparent, semi-solid or solid color, and it can be colorless too. Apply the sealant with or without stain in one brushing operation. For colored stains, you might want to add another coating to deepen the color. For transparent sealants, you only need one coat.