The Ontario Building Code | Joints Joints

(1) Lumber siding shall prevent water from entering at the joints by the use of lapped or matched joints or by vertical wood battens.

(2) Siding shall overlap not less than 1 mm per 16 mm width of lumber, but not less than,

(a) 9.5 mm for matched siding,

(b) 25 mm for lapped bevel siding, or

(c) 12 mm for vertical battens.

9.27.7. wood Shingles and Shakes