The Ontario Building Code | Stud Size and Spacing

9.23.10.1. stud Size and Spacing

(1) Except as provided in Sentence (2), the size and spacing of studs shall conform to Table 9.23.10.1.

Table 9.23.10.1.
Size and Spacing of studs

Forming Part of Sentence 9.23.10.1.(1)

Item	Column 1 Type of wall	Column 2 supported Loads (including dead loads)	Column 3 Minimum stud Size, mm	Column 4 Maximum stud Spacing, mm	Column 5 Maximum Unsupported Height, m
1.	interior	No load	38 × 38	406	2.4
			38 × 89 flat(1)	406	3.6
		attic not accessible by a stairway	38 × 64	610	3.0
			38 × 64 flat(1)	406	2.4
			38 × 89	610	3.6
			38 × 89 flat(1)	406	2.4
		attic accessible by a stairway plus 1 floor	38 × 89	406	3.6
		Roof load plus 1 floor
		attic not accessible by stairway plus 2 floors
		Roof load,
		attic accessible by a stairway	38 × 64	406	2.4
		attic not accessible by a stairway plus 1 floor	38 × 89	610	3.6
		attic accessible by a stairway plus 2 floors	38 × 89	305	3.6
		Roof load plus 2 floors	64 × 89	406	3.6
			38 × 140	406	4.2
		attic accessible by a stairway plus 3 floors	38 × 140	305	4.2
		Roof load plus 3 floors
2.	exterior	Roof with or without attic storage	38 × 64	406	2.4
			38 × 89	610	3.0
		Roof with or without attic storage plus 1 floor	38 × 89	406	3.0
			38 × 140	610	3.0
		Roof with or without attic storage plus 2 floors	38 × 89	305	3.0
			64 × 89	406	3.0
			38 × 140	406	3.6
		Roof with or without attic storage plus 3 floors	38 × 140	305	1.8

Notes to Table 9.23.10.1.:

⁽¹⁾ See Article 9.23.10.3.

(2) studs for walls not listed in Table 9.23.10.1. and supporting roof loads shall conform to Tables A-30 to A-33, provided,

(a) the studs are clad with not less than 9.5 mm thick plywood, OSB or waferboard sheathing on the exterior face, and not less than 12.5 mm gypsum board on the interior face,

(b) solid bridging is provided at not more than 1.2 m o.c,

(c) the studs are fastened to the top and bottom plates with no fewer than three 82 mm toe-nails,

(d) the double top plates are fastened together with not less than 76 mm nails spaced not more than 200 mm o.c,

(e) roof framing members spaced not more than 610 mm are fastened to the top plates with no fewer than four 82 mm toe-nails, and

(f) the bottom plate is fastened to the floor joists, blocking or rim joist with not less than 82 mm nails spaced not more than 200 mm o.c.