(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)
Thicknesses 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 400 mm o.c.,
(b)
not less than 9.5 mm thick on supports not more than 600 mm o.c., and
(c)
not less than 6.35 mm thick on supports not more than 600 mm o.c. in walls where blocking is provided at mid-wall height.
(5)
OSB conforming to CSA O325, “Construction sheathing,” shall meet the minimum panel mark of
(a)
W16, on supports not more than 400 mm o.c.,
(b)
W24, on supports not more than 600 mm o.c., and
(c)
W16, on supports not more than 600 mm o.c. where blocking is provided at mid-wall height.