First, make sure the plywood cornes from a mill that is a member of APA - The Engineered Wood Association. That is your assurance that the mill is subject to APA s rigorous quality assurance program. For use in boat manufacturing, the redrying of the treated plywood is essential to good performance when laminating with fiberglass. Treated plywood purchased from lumber yards is often used in construction applications and is not necessarily re-dried after treatment. It is essential for boat manufacturers to specify redrying.
Treated plywood is trademarked by a grading agency that monitors treating quality.
The trademark should specify the AWPA standard, treatment and treating retention. Many suppliers of treated plywood for the boat industry offer limited lifetime warranties. Check with your panel supplier for warranty information. For BEST performance of plywood in boat manufacturing, APA recommends the use of treated plywood according to the following specification. Treated in accordance to AWPA Standard C9 with to 0.40 pcf retention.