Can You Burn Pressure Treated Wood Outdoors?: 1 Minute to Understand the Risks and Alternatives

Burning pressure treated wood outdoors is not recommended under any circumstances. Pressure treated wood has been infused with chemical preservatives—such as chromated copper arsenate (CCA), alkaline copper quaternary (ACQ), or copper azole—to resist rot, insects, and fungal decay. When you burn this type of wood, it releases toxic chemicals and heavy metals into the air and leaves behind contaminated ash. The smoke is hazardous to inhale, and the toxic substances can settle in the soil or be carried by the wind, potentially contaminating nearby plants, water sources, and property. Even if you're outdoors and away from buildings, burning pressure treated wood poses significant health and environmental risks and is illegal in many jurisdictions.

Tips 1:

As an interior designer, I often encounter clients who want to repurpose leftover materials from construction or home improvement projects. If you have excess pressure treated wood, rather than burning it, consider using it for outdoor landscaping projects where its durability is advantageous—such as garden edging or raised garden beds (with a protective liner, to avoid direct soil contact). For safe and creative reuse, it's crucial to ensure the material remains intact and not subjected to processes that could release its chemicals into the environment. For new projects requiring safety and sustainability, planning materials and usage with a 3D floor planning tool can help optimize your selections and reduce waste from the start.

FAQ

Q: Is it ever safe to burn pressure treated wood outside?

A: No, burning pressure treated wood is never safe. The chemicals used in the treatment process are highly toxic and can cause serious health and environmental issues when released through burning.

Q: What chemical hazards are released by burning pressure treated wood?

A: Burning such wood can release arsenic, chromium, copper, and other poisonous compounds.

Q: How should I dispose of old pressure treated wood?

A: Take it to a local landfill or waste disposal facility that handles treated lumber. Many areas classify it as hazardous waste.

Q: Can I use pressure treated wood scraps in my fire pit or outdoor bonfire?

A: Absolutely not. For any type of recreational fire, use only untreated, natural wood.

Q: Are there environmentally friendly alternatives to pressure treated lumber for outdoor projects?

A: Yes, alternatives include naturally rot-resistant woods like cedar or redwood, or modern composite lumber that doesn’t require chemical treatment.