You’re likely to see signs advertising pressure treated wood the next time you walk through your local hardware store or a lumber yard. But what exactly does “pressure treated wood” mean, and how do they pressure treat wood? Keep reading to find out these answers and more.
How is wood pressure treated?
Professionals pressure treat lumber by immersing it in a liquid preservative and then placing it in a vacuum-sealed pressure chamber. The chamber forces the chemicals into the wood fibers and ensures they make it to the core of the piece. Before the lumber is soaked, it’s incised to guarantee the piece fully absorbs all of the protective chemicals. After the wood leaves the pressure chamber, it’s left out to dry for 24 to 48 hours.
Pressure treatment can be performed by either the full-cell or empty-cell process. The goal of full-cell treatment is to fill both the cell wall and the lumen with the chemical. In empty-cell treatment, professionals only want to soak the cell wall. Full-cell treatment is reserved for utility poles, farm fences, bridge timbers or other applications when a high concentration of chemicals is needed.
Another option to treat the wood would be to simply soak it in the protective chemicals. However, this is a much less effective and more time-consuming process.
What are the advantages of pressure treatment?
The chemicals used in pressure treatment serve as a barrier to protect the lumber from moisture, insects and other deterioration-causing forces. Pressure treated wood can last 20 to 25 years longer than wood that’s left untreated. Additionally, lumber can be pressure treated with fire-retardant chemicals that allow the wood to char quickly when exposed to heat, reducing smoke and flames.
Are there any downsides of pressure treatment?
Pressure treatment obviously has its advantages, and the answer to the question of how wood is pressure treated is pretty neat. But there are some people out there who argue that pressure treating wood isn’t safe.
The most commonly used chemical to treat wood is chromated copper arsenate (CCA). However, the use of CCA for residential settings has been banned by the U.S. Environmental Protection Agency due to concerns about arsenic leaching out of the wood. The alternative to CCA is alkaline copper quaternary (ACQ). While ACQ protects wood from fungi and insects, it can be harmful to the environment.
Does your lumber need pressure treatment?
Not all lumber needs to be pressure treated, but if your wood will be exposed to the elements, we recommend using pressure treated wood. Your structure will be safer and will last longer if you opt for pressure treated lumber.
Are you ready to start your construction project?
Now that you know the answer to how they pressure treat wood, it’s time to get started with your next residential or commercial construction project. Before you break ground, talk to our team at High Plains Engineering & Design, LLC. From framing plans to floor design, we offer a variety of structural engineering services to ensure your building is as safe and long-lasting as possible.
Categorised in: Pressure Treated Wood