The Ontario Building Code | Connection of Vents above Fixtures Served

7.5.6.4. Connection of vents above Fixtures Served

(1) Except for a wet vent, every vent pipe shall extend above the flood level rim of every fixture that it serves before being connected to another vent pipe.

(2) No vent pipe shall be connected in such a manner that a blockage in a soil or waste pipe would cause waste to drain through the vent pipe to the drainage system.