LISTEN...

Building must meet Part 9.25.3 Air Barrier Systems

9.25.3.2. Air Barrier System Properties

(1) Sheet and panel type materials intended to provide the principal resistance to air leakage shall have an air leakage characteristic not greater than 0.02 L/(s∙m2) measured at an air pressure differential of 75 Pa.

(2) Where polyethylene sheet is used to provide the air-tightness in the air barrier system, it shall conform to CAN/CGSB-51.34-M, "Vapour Barrier, Polyethylene Sheet for Use in Building Construction".

LISTEN...

Installation must meet Part 9.25.3.3 Continuity of the Air Barrier Systems

9.25.3.1. Required Barrier to Air Leakage

(1) Wall, ceiling and floor assemblies that separate conditioned spaces from unconditional spaces or from the ground shall be constructed so as to include an air barrier system that will provide a continuous barrier to air.

(a) from the interior of the building into wall, floor, attic or roof spaces sufficient to prevent excessive moisture condensation in such spaces during the heating season, and ...

*The requirement for inspection of air barriers has been in the code since 2012.