7.5.9.1 — Air Admittance Valve as a Vent Terminal

(1) Air admittance valves shall only be used to vent, (a) fixtures in buildings undergoing renovation, and (b) installations where connection to a vent may not be practical. (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 insulation materials, and (d) installed in a location not subject to back pressure. (3) Air admittance valves shall, (a) only vent fixtures located on the same storey, and (b) be connected to the horizontal fixture drain.

(1) Air admittance valves shall not be installed in supply or return air plenums, or in locations where they may be exposed to freezing temperatures. (2) Air admittance valves shall be installed in accordance with the manufacturer’s installation instructions. (3) Air admittance valves shall be rated for the size of vent pipe to which they are connected. (4) Installed air admittance valves shall be, (a) accessible, and (b) located in a space that allows air to enter the valve. (5) Every drainage system shall have one vent that terminates to open air in conformance with Sentence 7.5.6.5. (1).