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9.36.2.10. (9) The interfaces between windows, doors and skylights and wall/ceiling assemblies shall be constructed airtight by sealing all joints and junctions between the air barrier material in the wall and the window, door or skylight frame. (See Appendix A.) (See also Subsection 9.7.6.)

A-9.36.2.10.(9) Sealing the Air Barrier around Windows, Doors and Skylights . A continuous seal between windows, doors and skylights and adjacent air barrier materials can be achieved by various means including applying exterior sealant, interior sealant, low-expansion foam or sheathing tape in combination with drywall, polyethylene, a closed-cell backer rod, or a wood liner.

9.7.6.1. 3) Windows, doors and skylights shall be sealed to air barriers and vapour barriers