(1) Except as provided in Sentences (2) and (3), the minimum thickness of O-2 grade OSB used as an interior finish shall conform to that shown for plywood in Table 9.29.6.1.
(2) Thickness listed in Table 9.29.6.1. shall permit a manufacturing tolerance of -0.4 mm.
(3) No minimum thickness is required where O-2 grade OSB is applied over continuous backing.
(4) OSB conforming to O-1 grade, waferboard conforming to R-1 grade and particleboard shall be,
(a) not less than 6.35 mm thick on supports not more than 406 mm o.c.,
(b) not less than 9.5 mm thick on supports not more than 610 mm o.c., and
(c) not less than 6.35 mm thick on supports not more than 610 mm o.c. in walls where blocking is provided at midwall height.
(5) OSB conforming to CSA O325, “Construction Sheathing”, shall meet the minimum panel mark of,
(a) W16, on supports not more than 406 mm o.c.,
(b) W24, on supports not more than 610 mm o.c., and
(c) W16, on supports not more than 610 mm o.c. where blocking is provided at midwall height.