Last Updated on August 27, 2023 by Ernest Godia
As you lay pressure-treated wood on your deck, railing, and porch or erect it on your fence, sometimes it doesn’t fit right. You will have to cut the wood to get the length you prefer.
Looking at the face grain of the cut piece, you’ll notice that the pressure treatment reaches a specific level, and the center is natural wood. When you cut the pressure-treated wood, you expose the untreated part to moisture, heat, and mold. To prevent wood rot, you need to seal the cut ends.
This article looks at the best pressure-treated wood sealer for cut ends and guides you on how to seal pressure-treated wood cut ends.
What is Pressure-Treated Wood?
Pressure-treated lumber is wood preserved with chemical treatments to make it more durable than regular wood. Stacks of wood are placed into a pressure chamber known as a “retort.” The retort is a horizontal steel cylinder that looks like a rail car.
In the chamber, wood is subjected to chemical preservatives injected into the wood gain under pressure. After treatment, the lumber drips and dries till it cures.
Wood preservatives used for pressure treatment make the wood resistant to moisture, heat, and mold damage. Some chemicals like type C copper help wood retain its integrity even underwater.
When buying the wood, look at the tags indicating whether it’s for above-ground, ground contact, or marine use.
Best Pressure Treated Wood Sealer For Cut Ends
- Rust-Oleum Wolman Copper Coat Green Wood Preservative–Best resistance to moisture, mold, and mildew.
- Thompson’s WaterSeal Waterproofing Stain – Best value for the money.
- Ready Seal Exterior Stain And Sealer for Wood–Best stain and sealer in one coat.
- Cut-N-Seal – Best water-based formulation
- ANCHORSEAL Classic Log & Lumber End Sealer – Best for preventing moisture loss.
- Preservation Solutions End Grain Sealer–Best for preventing wood cracking and slowing down the drying process of wood treated with Pentacryl.
How To Seal Pressure-Treated Wood Cut Ends
You must seal the cut ends of your pressure-treated wood to prevent premature deterioration. Here is how to go about sealing:
What you’ll need
Below are the requirements for the project:
- End cut sealant
When choosing sealers, pick one with copper naphthenate, an essential compound. Copper naphthenate protects wood from insect damage, fungal rot, and decay. Most of the products in the market contain 1% copper, and that’s good enough to preserve the cut ends.
You’ll need a soft bristle paintbrush as an applicator. Read the manufacturer’s instructions on the number of coats to apply.
- Abrasing scrub
Use the abrasion scrub to remove any dirt or debris on the wood surface. The surface must be clean for the wood grains to absorb the sealant.
- Protective gear
Wear protective gear as the sealers emit toxic fumes, and direct contact with the product results in skin irritation.
Procedure For Sealing Pressure-Treated Cut Ends
Follow these steps to seal the cut ends of your pressure-treated wood. To seal the entire wood surface instead, read our article on sealing pressure-treated wood.
STEP 1: Choose the perfect day for the cut-end treatment
The weather needs to be about right for the job. Take your time and read the forecast to ensure it won’t rain on the day you apply the sealer and 2-3 days afterward. Most sealers take longer to dry, and water slows down the process.
It is also essential that you confirm the pressure-treated lumber is dry enough. Measure the drying level of the wood with a moisture meter by placing the pins or electrodes onto the wood and reading the levels on the screen.
The water absorption test is another way to check the moisture level. Pour some water on the wood with a glass and let it sit for 10 minutes. If the water is absorbed into the wood, it is dry enough, and if it beads up, the lumber is still too wet for sealing.
STEP 2: Choose the suitable sealant
When selecting sealers for pressure-treated wood, there are several factors to consider, such as:
- Check if the sealer is compatible with pressure-treated lumber.
- Confirm that the sealer’s color matches the pressure-treated wood’s color.
- Take note of where you are installing the wood. A suitable sealer protects lumber against harsh elements, mold, and mildew damage on exterior surfaces.
- Pick a sealer that blends in with your décor. Some sealants enhance the natural appearance of the wood, while others alter it completely.
STEP 3: Apply the sealant
First, test the sealer on an inconspicuous spot to confirm the color blends before applying it to a large area.
Then, apply it to the cut ends with a paintbrush or pad in thin and even coats along the wood grain. After the first coat dries, add a second coating. The number of coats depends on the manufacturer’s recommendation and the quality of the sealer you are using.
With every coat, run the brush over the edges as well. Most woodworkers cover the face grain and forget the edges because they seem sealed, but they get exposed when you cut the wood.
STEP 4: Let it dry
Give the pressure-treated wood ample time to dry. At least 24-48 hours without any moisture contact is good enough.
Reasons For Sealing Pressure-Treated Wood Cut Ends
Here is why you need to seal the pressure-treated wood’s cut ends:
- To prevent wood rot and decay. The pressure treatment only penetrates the lumber to a specific level, and the cut exposes the bare surface. Sealing protects the cut face grain from moisture damage, preventing fungal decay.
- Sealers contain copper green type C preservative, which protects wood from insect damage and microorganism infestation.
- Sealers help you add a splash of color to the pressure-treated wood or enhance the appeal of the natural wood.
- Sealers protect the pressure-treated wood cut ends from constant exposure to harsh elements and season changes. With time PT wood tends to crack, expand, and split due to rain and heat.
- Sealing the cut ends on your PT wood makes it more durable. If you don’t seal the exposed ends of the lumber on your deck or fence, you significantly reduce its lifespan.
Is It Okay To Cut Pressure Treated Wood?
Yes, wood doesn’t always come in the sizes you want, so you’ll need to cut it during your project. When cutting the PT wood, take precautionary measures to prevent exposure to harmful chemicals.
It is also important to note that the dust created during cutting should be disposed of accordingly. Keep the PT wood’s sawdust away from the garden or outdoors, as the chemicals can harm plants or animals and contaminate the soil.
Pressure-Treated Wood Sealer For Cut Ends: FAQs
Below are answers to some of the frequently asked questions related to the topic:
How to cut pressure-treated lumber?
When cutting regular wood, you typically place it on the table saw and run the saw through the wood or pull the wood towards you as the saw cuts. That isn’t the case with pressure-treated wood because if you try these methods, you risk chipping or splintering the lumber.
When cutting PT wood, let the saw do the work and pull the piece towards it. Tape the sections you intend to cut to minimize the level of chips and cracks.
Test the moisture levels of the wood, as moist lumber makes the saw blade slip, which risks chips and splinters. It is challenging to cut wet wood, especially for a newbie, as the cuts aren’t as clean and even.
Can you seal pressure-treated wood?
Absolutely! The reason why you go for pressure-treated wood in the first place is because of its weatherproof qualities. Cutting the lumber makes it susceptible to water, insect, and mold damage. To prevent these from happening, you must seal the cut ends. Apply 2-3 coats of the sealer and let it dry.
Where can you buy pressure-treated wood sealers for cut ends?
You can purchase pressure-treated wood sealers for cut ends from your local hardware store, Amazon, or the manufacturer.
What is the best deck end sealer?
To achieve a glossy finish on the ends, apply oil-based sealers and to get a splash of color, use the seal and stain combination. If you want a water-based sealer, go for Cut-N-Seal, as it’s easy to clean, ready to use, and has low odor.
Pressure Treated Wood Sealer For Cut Ends: Summary
The idea of using pressure-treated wood is the longevity it gives your fence boards, post tops, deck boards, and railing. Cutting the wood reduces its lifespan and renders lumber-like interior plywood useless. To minimize the damage, you need to seal your cut ends.
Sealing cut ends is a simple process that doesn’t hurt your pockets or consume much time. However, the outcome is worthwhile. Sealing protects the exposed wood fibers from water, insect, and fungi damage.
Remember to conduct a moisture test first before sealing the pressure-treated lumber. Also, keep the cut ends above ground.
Cut and seal all pressure-treated wood installations.