The Ontario Building Code | Air Admittance Valves
220.127.116.11. Air Admittance Valves
(1) Air admittance valves shall only be used to vent,
(a) fixtures inbuildings undergoing renovation, and
(2) The air admittance valves shall be located,
(a) above the flood level rim of the fixture it serves,
(b) within the maximum developed length permitted for the vent,
(c) not less than 150 mm above insulationhttp://thehandyforce.com/insulation/" title ="Toronto home insulation">insulation materials, and
(d) installed in a location not subject to back pressure.
(3) Air admittance valves shall,
(a) only vent fixtureslocated on the same storey, and
(b) be connected to the horizontal fixture drain.