Plywood vs OSB (Oriented Strand Board)
The following photo succinctly communicates the reason we use plywood wherever we have the option to.
The reality is, OSB needs special consideration when being used in an exterior sheathing application compared to good ole’ plywood. And this consideration is too often overlooked in many building designs.
As Dr. Lstiburek points out in his article, plywood breathes after it gets wet. OSB, not so much. Both products get wet and absorb moisture, but only one of them releases that moisture in an effective way that minimizes potential for deterioration and maximizes the drying effect.
The result is as shown in the photograph.
Great article from Building Science Corporation: Building Science Corp