Pressure-treated wood refers to wood that is preserved to improve its resistance to outdoor elements and prevent decay. But, its surface often has a green tint, creating a dull appearance. So, can you stain pressure-treated wood?
You can stain pressure-treated wood because its surface isn’t waterproof and it absorbs light coats of wood stain. However, you can’t stain it immediately after installation because the board comes wet so you need to leave it to dry.
If you stain it too soon, it will not accept the wood stain. You must only use exterior-grade oil-based wood stain on the pressure-treated wood as it’s weather-resistant and produces a durable finish.
How Long Must Pressure-treated Wood Dry Before Wood Stain?
You must wait until the pressure-treated wood is completely dry before 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.
You can stain old and already installed pressure-treated wood immediately as they are often dry. But, check the moisture content in the wood by driving a nail into the side of the board and pulling it out. If the nail is wet, leave the board to dry for a few days, if the nail isn’t wet, stain immediately.
Which Types of Wood Stain To Use on Pressure-treated Wood?
Use oil-based (exterior-grade) wood stain on pressure-treated wood. Pressure-treated boards are often used outdoors and exposed to outdoor elements, friction, foot traffic, dust, and cleaning liquids, so apply a finish strong enough to protect it from these elements.
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, use only 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?
To stain pressure-treated wood, do the following.
- Pick the Preferred Stain Opacity.
- Check if the Boards are Dry.
- Clean the Pressure-treated Wood.
- Do a Patch Test.
- Apply The Wood Stain.
- Apply Sealer Coat (Optional)
The tools you need are:
- Wood or deck cleaner
- Scrubbing brush
- Pressure washer or garden hose
- An exterior-grade wood stain
- Mineral spirits
- Polyurethane sealer (optional)
- Paint stripper (optional)
1. Pick the Preferred Stain Opacity
Pick the stain opacity you want. All types of wood stains; water-based or oil-based come in different opacities. You can choose a transparent, semi-transparent, or opaque finish.
Transparent finishes have a clear appearance on the surface and no color. Semi-transparent finishes have some color but still allow the grain to show. The opaque finishes hide 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 the Pressure-treated Wood.
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
Do a patch test before staining the boards. To do so, apply wood stain on a small area of the pressure-treated wood and leave it to dry.
Inspect the wood to see if it has absorbed the stain properly and the type of finish it has. If the wood has absorbed the stain properly and it has the type of finish you wanted, you are good to go.
A patch test is mandatory as it minimizes the chances of getting a bad finish.
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)
Pressure-treated boards are reinforced against rot and pest damage, but adding a clear waterproof coat will offer additional protection. This is an optional step.
You don’t have to seal the finish if you use exterior-grade stain as it has built-in sealer and plasticizers. But, if you still want to apply a sealer, use polyurethane.
After sealing the pressure-treated wood, use mineral spirits to dissolve and wash the painting equipment.
How To Maintain Stained Pressure-Treated Wood?
To maintain stained pressure-treated wood, do the following.
- Wipe and clean the surface regularly. You can use liquid deck cleaners to remove stubborn dirt and oily grime on the wood.
- 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.
- Repair holes and cracks in time. If you notice any cracks or holes in the boards, immediately repair them with caulk or joint compound. Pests and water can seep through these holes to damage the wood’s core.
- Seal the wood. A waterproof coating will shield it from damaging factors.
What are the Benefits of Staining Pressure-treated Wood?
The benefits of staining pressure-treated wood are listed below.
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. It 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. It makes Cleaning 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.