Can You Use Pressure Treated Wood for Interior Framing?

Interior framing, so Can You Use Pressure Treated Wood for Interior Framing?Pressure-treated wood has been around for around 60 years, and we can take pride in its longevity despite the seasons. In addition, it is suitable for multiple wood projects, especially outdoor ones, since it is insect and rot-resistant. However, many people have concerns if the lumber is safe for indoor use. Thus, the question Can You Use Pressure Treated Wood for Interior Framing pops up.

Yes. You can use pressure treated lumber for interior framing. The wood comes in handy where the frame touches the foundation. It keeps the basement safe from vermin infestations and fungus or mold attacks. But, treated lumber includes potentially toxic chemicals. Therefore, avoid using it on kitchen countertops or cutting boards.

I urge you to go through this article for more information and practical tips on handling pressure-treated wood.

Table of Contents

Why Not Use Pressure Treated Wood Indoors?

Pressure-treated wood should not be an automatic go-to solution for indoor projects as it has chemicals such as creosote. You may not see a problem until I tell you that creosote contains cresols, polycyclic aromatic hydrocarbons, and cresols.

These chemicals lead to health issues ranging from eye irritation, skin reaction to cancer. Also, the treated lumber may have diluted poison, and thus, if you have direct contact with it, the poison may seep through your pores. So, it would be best to avoid pressure-treated wood for home projects.

Also, having food around treated lumber is a concern. For example, if you use a cutting board from pressure-treated wood, the chemicals may get into the food and cause serious digestive problems.

The chemicals in treated lumber make it highly flammable. So, regardless of the wood’s indoor use, a small fire can get to uncontrollable levels once it reaches the treated wood.

In addition, we have homeowners who have used recycled wood from cross ties and telephone poles outside the home. This scenario poses a danger to those in tightly sealed homes as the wood materials usually contain high chemical levels. As a result, the residents can suffer from negative respiratory effects.

Can I Use Pressure Treated Plywood as Subfloor?

No. It would be best to avoid using pressure treated plywood as a subfloor. Instead, use normal floor sheathing. Also, you will experience too much shrinkage regardless of the material you use.

Luckily, you can use ACX Underlayment ply with waterproof glue, a higher crush rating, and no voids in the lams.

Is Pressure Treated Lumber Toxic?

Pressure-treated lumber is toxic. During the treating process, the wood is usually sealed in a vacuum. Then, the manufacturers add a solution containing copper, chromium, and arsenic. Please note that since the lumber is in a vacuum, the chemicals soak deeply.

The three chemical components give the lumber its ‘power.’ For example, copper is a fungicide, chromium is a bacteriacide, and arsenic is an insecticide. However, they are toxic, and while copper and chromium do not have deadly effects, arsenic is one element to avoid.

Arsenic is a metal-like element constituting oxygen, sulfur, and chlorine elements. It has two forms: organic and inorganic. The inorganic form is where we have the above elements, while we have carbon as an added element in organic arsenic.

Organic arsenic is not harmful, and people excrete it before it does any harm to the body. On the other hand, inorganic arsenic accumulates in living tissues and impairs cell enzymes and metabolism. Unfortunately, manufacturers use inorganic arsenic to pressure treat wood, making it dangerous to human health.

On top of that, pressure-treated wood’s fumes and ashes are as toxic as the raw chemicals. During burning, the cellulose burns and leaves behind ashes with more concentrated heavy metals. Also, the chemicals minus cellulose are soluble and toxic.

Remember that we can mention multiple things in the house that are unsafe upon burning. They include synthetic bags, plastic pipes, and drapers. So, like these things, do not burn treated lumber. Instead, take it to the dump or bury it.

Can You Get Sick From Pressure Treated Wood?

Pressure-treated wood can get you sick as it contains chromate copper arsenate. These elements lead to arsenic poisoning and cause death in case of extremely high exposures. Thus, although chromate copper arsenate (CCA) is useful to wood and keeps it from mold, termites, dry rot, and fungi, it is unsafe for your health. 

Frequent exposure to pressure treated wood dust can cause an incurable irritation to the bronchial tubes and lead to upper respiratory tract infection, asthma, and prolonged colds. In addition, bronchitis may become chronic despite minimizing the dust exposure. So, it is safer not to have any exposure at all.

Symptoms of arsenic poisoning include sore throat, nausea, abnormal heart rhythm, irritated lungs, decreased red and white blood cells production, vomiting, skin darkening, and extreme numbness. On top of that, it also causes various forms of cancer such as skin cancer, lung cancer, bladder cancer, kidney cancer, prostate cancer, and liver cancer.

Can You Put Pressure Treated Wood Directly on Concrete?

You can use pressure-treated wood when attaching furring strips or framing lumber to concrete or any other outdoor masonry walls. Even so, remember that concrete is highly porous unless you treat or coat it. Therefore, you can be sure that the walls will wick moisture on the wood.

In addition, treated lumber contains decay-resisting chemicals. Therefore, it helps keep the foundation as strong as possible. So, even if the concrete is damp, the treated wood will not decay as fast as normal wood.

Can You Use Pressure-Treated Wood For Floor Joists?

Nowadays, it is a building requirement to use pressure treated lumber wherever wood is in direct contact with masonry. The constructor bolts the wood to the foundation, where the floor joist rests. Therefore, since it is immune to damage, you have a safe base for the floor joist.

How Do You Use Pressure-Treated Wood Indoors?

You can use pressure treated lumber indoor as long as you factor in the risks and the safety measures. For example, ensure that you avoid it for surfaces that have food contact. In addition, it would be best to have protective gear whenever you interact with treated lumber.

Nevertheless, we cannot ignore the immense benefits of treated wood on other indoor applications. For instance, if your frames touch the foundation or concrete, pressure treated lumber helps keep the base in check. It is insect-resistance and thus, guarantees you a strong foundation.

Also, ensure that you keep the wood from regular moisture exposure, such as a window or leaking pipe. Although pressure-treated lumber is insect and rot-resistant, moisture damages it. Therefore, it would be best to treat it like any other wood and keep it away from moisture.

How Long Do Chemicals Stay In Pressure Treated Wood?

Researchers have found that arsenic levels in treated wood remain high for approximately 20 years. This conclusion comes about thanks to ‘wipe tests’ from s63 decks, picnic tables, sandboxes, and playsets in 45 states.

Unfortunately, the suggested duration is quite significant as it represents the wood’s useful life. Therefore, you should not use treated lumber, hoping that the chemicals will dissolve in the atmosphere.

How Do You Treat Pressure Treated Wood After Cutting?

There are various options to pick from once you cut pressure treated lumber. One of them is sealing the wood, which gives it water-resistance attributes. Also, maintaining a sealed end is very important when applicating the treated wood into the ground. So, after you cut the lumber into fence posts, it would help if you seal it.

In addition, sealing the pressure treated wood protects it from fading, warping, and discoloration.

However, the treated lumber only responds to the sealant if you allow it to dry completely.

Wet wood swells and repeatedly shrinks which causes checks, splits, cracks, and splinters. Therefore, be patient and allow the wood some dry time.

What Happens If You Inhale Smoke From Pressure Treated Wood?

Smoke inhalation happens when you breathe in dangerous gases or smoke particles. It causes lungs’ inflammation and causes them to swell and block oxygen. This scenario ultimately leads to respiratory failure or respiratory distress syndrome.

The situation is no different from inhaling smoke from pressure treated wood. Unfortunately, it is even worse than normal smoke. The treated wood releases dangerous fumes, as we have discussed in the above sections. Therefore, you can expect more severe effects such as cancer and asthma.

If you have pressure-treated wood in the house, ensure that you have smoke detectors in all the sleeping rooms and every other home area. Also, remember to replace the detectors’ batteries every year to keep them functioning.

In addition, treated wood is more flammable than normal wood. So, do not leave pace heaters, cigarettes, or lit candles unattended.

How Long Will Pressure Treated Lumber Last With Ground Contact?

It depends on the climate, how you use the lumber, the wood type, and how well you maintain it. So, if you do everything right, the pressure-treated wood should serve you for as long as 40 years without showing any decay or rot signs.

Additionally, you can enhance its longevity by applying water-repellent sealers yearly. Also, mildewcide cleaners will help you to get rid of any mildew growing on the wood.

When Did They Stop Putting Arsenic in Pressure Treated Wood?

Most of the treated wood in stores before January 2004 has chromate copper arsenate. The arsenic components are common for causing cancer in humans upon swallowing. However, the Environmental Protection Agency halted the use of CCA-treated lumber for residential projects.

Can You Burn Really Old Pressure Treated Wood?

It would be best to get other wood disposal methods apart from burning when working with pressure treated wood. The chemical components in the lumber stay intact for decades, and even if it is old, the fumes are harmful to human health.

In addition, the three dominant components in treated lumber may become airborne. They will end up in the ash and are highly leachable to groundwater. This situation causes a ton of environmental concerns. Therefore, you should not burn this wood in fireplaces, stoves, or outdoors.

Fortunately, it is legal to dump the treated wood in the landfill if you don’t want to reuse it.

Is It Necessary to Seal Pressure Treated Wood?

Pressure-treated lumber should have frequent sealing annually to preserve it from moisture. Though the wood is insect and rot-resistant, it can still split, warp, and develop mildew if you expose it to water. Therefore, consider the following sealants to keep the wood safe and useful for an extended period.

  • Ready Seal Stain and Sealer for Wood

The product is a common name for most homeowners who want stain and sealer features in one solution. Therefore, they save the time and money needed for wood treatment without significant losses.

In addition, the formula saves the wood from harmful UV rays and any extra moisture in the environment. Also, you can apply it without adding a primer, and it had a rich color palette to help you get the best color for your lumber.

Ready Seal does not leave laps, streaks, and runs on your wood surface. Also, you don’t need to thin or dilute it before spraying applications, and you can apply it at any temperature range.

  • Thompson Waterseal Clear Waterproof Wood Protector 

This formula preserves the wood’s original color by preventing outer effects such as graying, fading, and darkening. It also prolongs the lumber’s life and appearance by preserving it from extra liquids.

Besides that, the product keeps the redwood color for an extended period by creating a shield against mildew and negative UV effects. Also, it is an environmentally friendly sealant that is safe for use.

  • Cabot Australian Timber Oil

Cabot is a perfect option for wood decks, railings, and house sidings. It also works for both exterior and interior wood projects. So, it is suitable for multiple applications. On top of that, it has a linseed formula that allows it to penetrate deep into the wood.

Also, you don’t have to worry about negative UV rays effects because the oil has translucent iron oxide pigments. 

  • #1 Deck Premium Semi-Transparent Water Based Deck Stain

This stain is quite fascinating as it has a matte effect that works on damp wood. Hence, you can apply it immediately after cleaning and brightening the lumber. Also, it protects the surface from peeling, graying, and fading to give it a beautiful look throughout its useful life.

#1 Deck Premium protects the lumber from potential damage because of outer elements such as UV rays and excessive moisture. However, it would be best if you do frequent maintenance coats for hardwoods.

  • DEFY Extreme Semi-Transparent Exterior Wood Stain

This exterior wood stain features the zink nano-practice technology that keeps the wood surface from color loss or graying. Thus, the lumber maintains a perfect semi-transparent finish. This formula also works for multiple wood projects such as outdoor furniture, players, siding, arbor, and fences.

You do not need to have expertise experience to maintain the stain properly. Simply begin by brightening the wood surface with the recommended brightener. Then, apply one layer of the formula.

On top of that, the product has multiple colors that you can choose from, and thus, you can get the best one for your project.

That said, let me add that it is essential that you use the correct sealing procedure. So, let me give you some tips to get you started.

  • Check the moisture content on the lumber’s surface because bare wood should be dry before sealing. In addition, you can use a moisture meter just to be sure that you have the correct moisture levels.
  • Prepare the wood for staining by using a professional primer. Also, you can use a shellac-base primer as it offers the perfect results. It does not have an odor and disappears shortly after application.
  • A primer keeps the wood from possible knots and prevents bleeding through the last or finish layer. However, in case the stain has knots, you do not need to use a primer. 
  • Consider having a nest treatment to remove all the oozing sap, especially if you work with fir or pine. Then, apply the primer or sealer.
  • Fill all the cracks or holes on the lumber’s surface with a professional wood filler. Also, use a high-grade filler to keep the crack from shrinking.
  • Sand in the grain direction because an otherwise motion will lead to multiple surface scratches.
  • Use a clean brush and move it quickly and evenly during the sealing process. Also, be sure to check that the solution covers the surface correctly, especially the end grains.
  • Give the sealer a one to two hours drying period, then sand the surface.
  • Ensure that you examine the results after the first coat because some woods require more than one coat to give a desirable finish.

We have multiple pressure-treated wood sealers that you can choose from, and thus, a guide on the selection strategy will help. Let’s then check some of the major considerations to make before you purchase a formula.

  • The Wood Type

It would be helpful to assess the type of wood you want to coat as there are various products. You will get some suitable for softwoods and others perfect for hardwoods. Therefore, once you understand the wood, you can get an ideal formula. 

Also, various wood protectors feature different curing times. So, you need to choose the product that offers the shortest drying time for the wood.

  • Application

How you apply the stain or sealer matters and depends on the product you choose. For example, we have products that work well with brushes, while others give desirable results if you spray them.

  • The Type of Sealer or Stain. 

We have water and oil-based stains that offer different benefits. For example, water-based stains are non-flammable, while oil-based solutions offer more wood protection as they have special oils.

  • The Desired Finish

The outcome will also determine the stain that you will buy. So, it would be best to choose a semi-transparent or transparent formula if you want to keep the wood’s original color.

On the other hand, if you desire a more protective coat, it would be best to consider applying many layers. Generally, the more layers you have on the wood, the stronger the finish.

  • Environmentally Friendly

It is our responsibility to keep our surroundings safe from harmful or toxic fumes and chemicals. Therefore, even as you shop for a stain or sealer, it would be prudent to get one that does not contribute to health hazards.

Ensure that you examine the product’s packaging as most manufacturers indicate the VOC levels to expect in the formula.

  • User-friendliness

Try to select sealers that you can easily apply with a brush, pad, or sprayer. Also, get a formula with no or extremely low odor and one that you can remove if you make a mistake.

In addition, you will also enjoy working with a formula that is easy to understand. Some formulas have multiple specifications that can confuse a novice.

  • Durability

Durability is among the primary reasons why you purchase a stain or sealer. Therefore, it should be an essential factor to consider. Ensure that it is of high quality and can last at least two to three years.

In addition, it would be best if you get a product with a three to ten years warranty.

What Type of Saw Blade is Best for Cutting Pressure Treated Wood?

Treated wood is usually fibrous, wet, and corrosive. So, ensure that you cut it with a circular saw. Also, the saw should have wide, deep gullets and widely spaced carbide teeth to keep the blade from any clogs.

In addition, assess the saw for a coating as it guards the metal against corrosion and keeps it from sticking in the kerf.

More specifically, we have the general-purpose wood saw blade. It is perfect for cutting plywood, pine, beams, oak, and pressure-treated wood. The saw also leaves a smooth cut, and you don’t need to keep changing blades after each task.

What Happens When You Cut Pressure Treated Wood?

You produce sawdust during a pressure-treated wood cutting session. That is obvious for any wood, right? Well, it may be an expected outcome, but treated sawdust is not safe for your health.

Therefore, always wear gloves, eye protection, and a dust mask whenever you cut pressure-treated lumber.

Frequently Asked Questions

  • Does Pressure Treated Wood Dull Saw Blades?

Generally saw blades dull because of age and frequent use even before the chemical sauce any noticeable damage. However, since preventing a situation is better than looking for curative measures, it would help cut several untreated wood pieces. Then, apply a cloth with some synthetic oil and use it to clean the blade.

  • When Should I Stain My Pressure Treated Wood?

Staining wet treated wood may not give you the desired results because it is usually swelled when dump. So, when you stain it, it may have cracks and splits later.

Therefore, it is prudent to wait for the pressure-treated lumber to dry completely before any application. Also, the chemicals in the wood may leave additional moisture in the wood fibers, which may compromise its longevity.

  • What Happens if You Paint Pressure Treated Wood Too Soon?

As we now know, wet treated wood is a bad recipe for painting, sealing, or staining. Therefore, you should avoid painting the treated wood as soon as you purchase it because it may still be wet.

Also, the paint or primer coat will not adhere to wet treated lumber as the chemicals bleed out slowly.

  • How Do You Protect Pressure Treated Wood?

Start by cleaning the lumber with a brightener or cleaner that has mildewcide. Then, use a water-repellent on the wood’s surface for enhanced protection against excess moisture.

Also, it would help to have annual maintenance sessions to keep the pressure-treated wood in its best shape.

  • How Do You Keep Pressure Treated Wood From Cracking?

Drill a pilot hole before driving in a screw or nail to avoid splitting the wood. It also helps to fasten near the board’s end as the lumber shrinks when it dries out.


Pressure-treated lumber is an excellent solution to short-lived natural wood. It guarantees you an incredibly long lifespan, and all you need to do is adopt simple maintenance strategies such as sealing, painting, sealing, or varnishing. But, we still need to know when and where to use it to achieve optimal results. Thus the question:

Can You Use Pressure Treated Wood for Interior Framing?

The answer is a simple yes! You can get treated wood for interior framing projects. You will not have to stress about insect attacks or wood decay on your foundation. Therefore, if you can get pressure-treated lumber for your work, why not?

However, we cannot ignore the health concerns about using pressure-treated wood indoors. The fumes from the lumber cause tons of health issues, requiring you to be careful where you use it. For example, please avoid having cutting boards or kitchen surfaces made of treated wood as the chemicals may get into food.

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Tyron Otieno

Tyron is an avid woodworker and writer. He founded this website to help other woodworkers, whether hobbyists or professionals by sharing his knowledge and experiencie after a decade of woodworking.