Photo Source: Summerhill

Photo Source: Summerhill

9.36.2.10. (14) Ducts that penetrate the building envelope shall be constructed airtight by sealing the penetration through the building envelope.

(15) Plumbing vent stack pipes that penetrate the building envelope shall be constructed airtight by

a) sealing the air barrier material to the vent stack pipe with a compatible sealant or sheathing tape, or

b) installing a rubber gasket or prefabricated roof flashing at the penetration of the plane of airtightness then sealing it and mechanically fastening it to the top plate.