The Ontario Building Code | Thickness

9.29.6.1. Thickness

(1) Except as provided in Sentences (2) and (3), the minimum thickness of plywood interior finish shall conform to Table 9.29.6.1.

Table 9.29.6.1.
Thickness of Plywood interior Finish

Forming Part of Articles 9.29.6.1., 9.29.6.2. and 9.29.9.2.

Item	Column 1 Maximum Spacing of supports, mm o.c.	Column 2 Minimum Thickness, mm(1), on supports with no Horizontal Blocking	Column 3 Minimum Thickness, mm(1), on supports with Blocking at Vertical Intervals not exceeding 1.2 m
1.	406	4.7	4.0
2.	610	8.0	4.7

Notes to Table 9.29.6.1.

⁽¹⁾ Thickness limits shall apply to the net effective thickness (NET) of grooved, striated, textured and/or embossed panels and to the actual thickness of flat panels.

(2) A manufacturing tolerance of -0.4 mm may be applied to the thicknesses listed in Table 9.29.6.1.

(3) No minimum thickness is required where plywood is applied over continuous backing.