The Ontario Building Code | Insulating Sheathing in Lieu of Sheathing Membrane

9.27.3.4. insulating Sheathing in Lieu of Sheathing Membrane

(1) Where non-wood-based rigid exterior insulating sheathing, or exterior insulating sheathing with an integral sheathing membrane is installed, a separate sheathing membrane is not required.

(2) Where insulating sheathing is installed as provided in Sentence (1),

(a) sheathing panels subject to moisture deterioration shall be sealed at all joints, and

(b) the joints of sheathing panels not subject to moisture deterioration shall be,

(i) sealed at all joints, or

(ii) lapped or tongue and groove, and detailed to ensure drainage of water to the exterior.