Uploaded May 2021 | Updated September 2026, 1 week ago

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Read the full post: dunnlumber.com/blog/post/a-history-of-pressure-treated-lumbers-chemical-composition

Treated lumber is a popular building material that has played a key role in the construction of many of our structures in the Pacific northwest. In this series, our good friend and expert in pressure treated wood, Dennis McWhirter of Exterior Wood, answers common questions about treated wood.

In this video, we ask: Has the chemical process for treating lumber changed over time?