(1)
Plywood roof sheathing shall be installed with the surface grain at right angles to the roof framing.
(2)
OSB roof sheathing conforming to CSA O325, “Construction sheathing,” or to O-1 and O-2 grades as specified in CSA O437.0, “OSB and Waferboard,” shall be installed with the direction of face orientation at right angles to the roof framing members. (See Note A-9.23.15.4.(2))