A composite engineered wood material piece and its method of fabrication is described. The wood material piece comprises a top wood layer secured to a substrate layer by a binder. The substrate layer has a plurality of grooves formed therein from a bottom surface thereof to enhance the flexibility of the wood material piece. The grooves are spaced from one another by one or more predetermined spaced intervals and have one or more predetermined depth and width calculated to substantially eliminate the effects of telegraphy of the grooves on a top finished surface of the top wood layer.