What is CDX plywood?

Article Type: 
Updated: 
Wednesday, March 23, 2011

Everyday plywood is graded from A to D. Grade A plywood is perfect, with no knotholes. D grade has gaping knotholes.
CDX plywood has a C side and a D side. It's ugly, and less expensive than the better-looking plywood. Exterior-grade plywood, designated by the letter X, will not de-laminate when wet.