The Window & Door Manufacturers Association (WDMA) has received requests from suppliers under the Preservative Treatment for Millwork Certification Program for approval of chemically modified wood barrier treatment systems. Accordingly, for the benefit of these licensees, WDMA has reviewed tests results and supporting information of these systems for compliance with the WDMA I.S.4 requirements. These tests revealed that the following chemically modified wood processes identified in the WDMA I.S.4, “Industry Standard for Preservative Treatment of Millwork”, and are acceptable for use under the WDMA Preservative Treatment Certification Program. Chemically modified systems on this page have a third party review demonstrating that FIFRA does not apply. The systems that are exempt from FIFRA requirements shall not be marketed as preventing decay and rot.

Note: This listing is not intended to be a complete list of chemically modified wood that conform to WDMA I.S.4, but rather, it is a list of those products that have been submitted to WDMA for review and approved.  WDMA makes no claims as to the availability or suitability of the in-process treated products listed.