With some exceptions, plywood is graded on the basis of the size and number of defects per unit of surface measure, square meter (10.765 square feet). A higher grade would have a larger area of clear (defect free) surface.
The Grades are classified into three categories: Superior Grades (B) Select Grades (BB) Structural Grades (CP, C)
Superior and Select Grades have been designed primarily for the furniture and cabinet industry. However any industrial customer may enjoy a wide selection of grade combinations that provide the best quality-to-price balance.
Structural grades enable to make the most of birch plywood strength advantages especially for the building industry (e.g, sheeting and floor underlayment).
Each plywood piece is graded from two faces and described as a combination of front/reverse face quality, e.g. B/BB, BB/CP etc. When the front and reverse faces of a panel are of the same quality, the panel is described by one grade, e.g. B, BBSelect, BB etc.