A. Adam Taylor, the wood-products extension specialist at the University of Tennessee, responds: The short answer is yes, micronized-copper treated wood can be used in load-bearing and ground-contact applications. However, a little more background information might be helpful.
Treated lumber is widely used for decking and other exposed woodwork. The treatment process uses vacuum and pressure to force preservative liquids deep into the wood. After treatment the water evaporates, but the chemicals remain to protect the wood.
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