When Should I Use Treated Lumber?

As you contemplate an upcoming construction project, you wonder what type of lumber will be the right choice for your needs. Hardwood or softwood? Engineered? Specialty or standard?

At STAR Building Materials in Winnipeg, one of the most common questions we field from our customers is about the difference between treated and untreated lumber. If you're not 100% sure when or why treated lumber may be your best choice, you're certainly not alone.

In this post we'll delve into the world of treated lumber and explore its benefits and applications as well as some considerations to keep in mind when using it. We'll also look at how to safely work with treated lumber and finish off with some specifics about the brown pressure-treated wood products we are proud to maintain in our inventory.

If, after reading this post, you're still uncertain whether or not treated lumber will be the right fit for your circumstances, a friendly and knowledgeable STAR team member will be happy to offer advice. As a quality provider of Winnipeg building supplies, we're always ready to serve you!

What Is Pressure-Treated Lumber?

Pressure-treated lumber is a popular product made by placing wood in a vacuum to remove air from its cells and then infusing it with a chemical preservative instead. Resistant to damage from moisture, pests, and rot, it's ideal for outdoor projects where untreated wood would decay much more rapidly.

Historically, the primary preservative agent in pressure-treated lumber, CCA, was derived from arsenic, but this agent was banned for commercial applications in 2004. Since then, copper has become the primary ingredient in most treated wood products, which has increased their safety (see more below) but also driven up their price.

There are two main categories of pressure-treated lumber:

• Above Ground - These products are designed for exposure to the elements, but not meant to remain in constant contact with soil, cement, or other moisture-retaining surfaces.
• Ground Contact - These products are specifically designed to be in constant contact with soil, cement, or other moisture-retaining surfaces. They can even be buried underground and maintain their integrity over long periods of time.

In addition, both categories of pressure-treated wood come in two grades: Grade 1 and Grade 2. Grade 1 has less flaws and blemishes and is aesthetically more suitable for portions of projects that will be visible when completed.

Benefits of Pressure-Treated Wood

The primary benefit of pressure-treated wood is that it’s resistant to damage and decay from:

• Moisture - Ideal for applications where ongoing exposure to moisture is expected
• Insects and Pests - Repels termites, carpenter ants, and other wood-gnawing insects and pests
• Mould and Rot - It's almost impossible for fungus and bacteria to get a foothold

Pressure-treated wood is much longer lasting than standard lumber, often boasting a lifespan of twenty years or more, even in unfavourable conditions.

Considerations When Using Treated Lumber

When used properly, treated lumber is a safe and straightforward product. But there are a few considerations to keep in mind before you begin sawing and hammering:

It's important to be aware that, due to the treatment process, pressure-treated lumber is often still saturated (or even wet) upon purchase. As the product dries over time, the chemical preservative may leak out, causing shrinkage (and, occasionally, warping). Such leakage can also sometimes make painting or staining treated wood a challenge. Using a clear sealant is recommended (which also helps prevent corrosion and seepage of chemicals into the surrounding environment).

Staying Safe

As with any product that contains chemicals, it's important to take proper precautions when handling preservative treated wood. Protect yourself with a mask when cutting it and clean up sawdust as quickly and thoroughly as possible. In addition, you should never burn treated wood; always dispose of unwanted pieces at the dump. Sealant is recommended in general, but especially in circumstances where children or pets will be in regular contact with treated wood products (such as on playground equipment).

Common Applications for Pressure-Treated Lumber

Common applications for pressure-treated lumber include:

• decks
• railings
• playground equipment
• fences
• basements (against masonry walls)
• boardwalks
• retaining walls
• outdoor wooden structures
• any other construction that will be continually exposed to moisture

When is Pressure-Treated Wood Not the Right Choice?

In general, pressure-treated wood isn't the right choice for:

• most interior applications
• situations where it may cause corrosion to untreated steel or aluminum
• woodworking projects
• settings that involve sustained contact with food, drinking water, young children, or pets

Brown Pressure-Treated Lumber

At STAR Building Materials, we are proud to offer a wide selection of West Fraser's Barefoot brown-treated wood products, which are long-lasting, resilient, economical, and must meet high standards for optimal preservative treatment. All of our brown-treated wood products are kiln-dried and graded for quality before being treated. In addition, they're sourced from certified, sustainably managed forests, making them an environmentally-friendly option.

If you're looking for treated lumber in Winnipeg, look no further than the superior products that we consistently stock at STAR Building Materials. Available in a spectrum of standard sizes, they're perfect for a wide range of outdoor summer projects. Visit us today to get started!