Subflooring in the kitchen and bathroom may also be pressure treated since water leaks are common in these rooms and subflooring is inaccessible to the residents.
What are subfloors usually made of?
Typically made of plywood or OSB and ranging in thickness from 19/32" to 1 1/8" thick, the subfloor is truly structural, second only to joists in this respect. Subfloor holds up all of the above layers of flooring, as well as everything in your house, including people, dogs, cats, pianos, furniture.
How do I know if my wood is pressure treated?
How Can I Differentiate Treated Lumber? Most pressure treated lumber will have an end tag to identify what type of chemicals it was treated with and whether it is rated for “ground contact” or “above ground use” only.