Treated lumber is a popular building material that plays a key role in the construction of many structures in the Pacific Northwest. Our good friend Dennis McWhirter is an expert on pressure-treated wood, with nearly three decades of experience in the industry. In this series, Dennis provides answers to some common questions, and reminds us why treating lumber is one of the best things we can do to help preserve our greatest renewable resource.

Just like any building material, there are certain things you should avoid doing with treated lumber. In this video, Dennis shares important information about what happens when you burn pressure-treated lumber, and why you should seek out a different method of disposal. 

Can you burn pressure-treated lumber?

Pressure-treated lumber is a wood product that burns just the same as any other wood; so, technically speaking, you can burn it. 

Should you burn pressure-treated lumber?

While pressure-treated lumber is technically wood, you should not burn it, as its preservation chemicals include copper, which is a heavy metal. When you burn pressure-treated lumber, some of those chemicals will rise up into the atmosphere with the heat of the fire and pose no human threat; however, the biggest concern is the copper that remains on the ground in the ash. Burning a small piece on occasion isn't detrimental, but burning pressure-treated lumber on a continuing basis (or in large amounts) runs the risk of higher copper concentration in the ash. If the ash isn’t disposed of properly (i.e., if you toss it on the ground rather than in a trash bin), heavy metals can contaminate the dirt, which can pose health risks.  

Like any construction material, pressure-treated wood comes with important do’s and don’ts, and we’re here to help guide you through them. Looking for more information on pressure-treated lumber? Check out Dennis’s breakdown of how pressure-treated lumber is made, or check out the rest of the videos in our treated lumber series.