Can You Stain Pressure-Treated Wood? (& How-To)

Pressure-treated wood is reinforced with chemicals to prevent rot but they often leave a green tint on the surface, creating a dull appearance. Like you, many homeowners wonder if they can improve the dull appearance with a wood stain. So, can you?

You can stain pressure-treated wood because it isn’t waterproof. This means the wood will absorb light coats of stain. However, you can’t stain it immediately after installation because the board usually comes wet so you need to leave it to dry.

If you stain it too soon, it will not accept the wood stain. Also, you should only use exterior-grade oil-based wood stain because it is weather-resistant and produces a durable finish.

Dry Time Before Stain

You must wait until the pressure-treated wood is completely dry before you can apply wood stain. The drying time is determined by the type of pressure-treated wood you have.

The process of creating pressure-treating wood involves mixing chemicals and preservatives with water. The chemical mixture is then injected deep into the pores for the wood to absorb. This is why fresh pressure-treated boards often have high-moisture content. 

If you have just purchased it, you must wait several weeks for it to dry before it can accept wood stain. It’s also not advised to install it immediately. You should leave it for a few days, so the chemicals can work.

ADAT (air-dried after treatment) and KDAT (kiln-dried after treatment) pressure-treated boards can be stained a few days after installation. This is because these boards have been dried using the Klin process.

The Klin process involves putting fresh boards in a chamber where humidity, temperature, and air circulation can be controlled to reduce the moisture content in the wood. After installing ADAT and KDAT pressure-treated boards, you must wait 2-3 days for the glue between the boards to dry before staining.

For old and already-installed pressure-treated wood, you can stain them immediately because they are often dry. However, you should still check the moisture content in the wood – Drive a nail into the side of the board and pull it out. If the nail is wet, you should leave the board to dry for a few days.

Types of Stains To Use

The best type of stain to use on pressure-treated wood is oil-based exterior-grade wood stain. This is because pressure-treated boards are often used outdoors and subjected to harsh conditions, friction, foot traffic, dust, and cleaning liquids, so you need to use a finish that is strong enough to protect it from these harsh conditions. 

Oil-based wood stains penetrate the pores deeply, which means they have good adhesion to the surface. Also, its glossy finish will make the boards resistant to moisture and dirt stains, so cleaning and maintenance would be easy. They also highlight the beauty of the wood grain.

Water-based wood stains can also be used but they don’t offer the same finish and protection as oil-based stains. Unlike oil-based stains, latex stains hide the wood grain and they aren’t as resistant to moisture and UV damage.

So, you must only use exterior-grade stains because they are reinforced with additives that make the finish resistant to UV deterioration and water damage.

How To Stain Pressure-Treated Wood?

The tools you need are:

• Wood or deck cleaner
• Scrubbing brush
• Pressure washer or garden hose
• An exterior-grade wood stain
• Paintbrushes
• Rags
• Mineral spirits
• Polyurethane sealer (optional)
• Paint stripper (optional)

1. Pick Your Preferred Finish

First, choose the type of finish that you want. All types of wood stains; water-based or oil-based come in different types of finishes. So, you can choose a transparent, semi-transparent, or opaque finish.

Transparent finishes have a clear appearance on the surface and no color. A semi-transparent finish has some color but still allows the grain to show. The opaque finish hides the grain. It has the most color and also offers the most protection from UV rays. So, make your choice.

2. Check if the Boards are Dry

Next, check the moisture content in the boards because they can only be stained when dry. To do this, drive a nail into the side of the board and pull it out. If the nail is wet – there’s still moisture in the wood and you should leave it to dry some more.

You can also try the water bead test. Sprinkle some water on the boards and leave it for a few minutes. If the water is absorbed, it means the boards are dry and ready to accept the wood stain. If the water beads on the boards, it means they can’t absorb stain yet.

3. Clean

New pressure-treated wood is usually clean, so you don’t have to remove dirt stains. However, old treated boards and already-installed decks and fences would have dirt and grime on them, so you need to wash them.

Start by using a scrubbing brush to remove loose filth. Then, apply wood or deck cleaner directly on the boards and finish off with a pressure washer. After washing, leave the boards for several hours to dry.

4. Do a Patch Test

Before staining the entire boards, try a patch test first. This means applying wood stain on a part of the pressure-treated boards and leaving it to dry.

Then, inspect the finish to see if the wood absorbs the stain properly. You also must check the type of finish that you got, and see if it’s the same that you wanted. A patch test ensures you get a smooth finish, so don’t skip this step.

5. Apply The Wood Stain

If the patch test gives good results, you can stain the entire boards. Since pressure-treated boards are often used outdoors, you must check the weather conditions and ensure to stain them when there is no chance of rainfall or snow.

If all is clear, mix your wood stain and apply it using light brush strokes. Don’t backstroke wood stain because it counts as an additional coat, and can make your finish look patchy or uneven. Instead, use single light strokes.

If you are working on a fence, start from the top and work your way down. You only need 2 coats of wood stain on the wood. Remember to wipe off the excess stain with a clean rag, so you don’t end up with a patchy finish.

6. Apply Sealer Coat (Optional)

Although pressure-treated boards are reinforced against rot and pest damage, adding a clear waterproof coat over the stained wood will offer additional protection. This is an optional step.

If you used an exterior-grade stain, you don’t have to seal the finish because its finish often has built-in sealers and plasticizers. If you want to seal, a good choice is a polyurethane.

After application, use mineral spirits to dissolve and wash your equipment immediately.

How To Maintain Stained Pressure-Treated Wood?

Here are expert tips on how to do it:

1. Wipe and clean the surface regularly: You can use liquid deck cleaners to remove stubborn dirt and oily grime on the wood.
2. Invest in a carpet. Decks built with pressure-treated wood are subjected to high foot traffic, scratch marks, and weight that can dent them. Using a carpet will prevent dents and damage marks on your deck.
3. Repair holes and cracks in time. If you notice any crack or hole in the boards, immediately repair it with caulk or joint compound. Pests and water can seep through these holes to damage the wood’s core.
4. Seal the wood. A waterproof coating will shield it from damaging factors.

Benefits of Staining Pressure Treated Wood

Here are reasons you should stain pressure-treated boards. 

1. It Beautifies the Surface

The chemicals used to treat pressure-treated wood penetrate deep into the wood structure. Though this improves its durability, it leaves a lot to be desired in appearance.

So, staining them will give a beautiful appearance befitting of your home. You can also pick the color and type of finish that you want, making it easier to match it with your home décor. Staining the boards can also increase the monetary value or worth of your home.

2. Prevents Surface Cracking

It’s common to notice cracks and splits on pressure-treated wood after a while. The cracks are formed as the boards cure over time.

Also, the constant wetting and drying of the boards due to exposure to the elements can put pressure on its top layer causing hairline cracks. So, staining prevents these cracks because the top layer of the boards is covered.

3. Cleaning is Easier

Staining pressure-treated boards makes cleaning and maintenance easier. Exterior-grade wood stains are usually dirt-resistant, so you won’t encounter much dirt on your front deck or fence.