What kind of wood underlayment is approved by NAFCO?
NAFCO recommends a minimum of 1/4-inch American Plywood Association (APA) approved plywood be used; this is the best underlayment for our products. We also allow the use of lauan, but it must be exterior grade, Type 1 Exterior that has a fully waterproof glue bond. The acceptable types are designated with the letter “P” and the acceptable face grades are “CC” and “BB”.
