The Ontario Building Code | Direct Connections
7.4.2.3. Direct Connections
(1) Two or more fixture outlet pipes that serve outlets from a single fixture that is listed in Clause 7.4.2.1.(1)(d) may be directly connectedto a branch that,
(a) has a sizeof at least 1 ¼ in., and
(b) is terminated above the flood level rim of a directly connected fixture with a minimum diameter waste of 1 ½ in. to form an air break.
(2) Fixture drainsfrom fixtures that are listed in Subclauses 7.4.2.1.(1)(d)(i) and (ii) may be directly connectedto a pipe that,
(a) is terminated to form an air break above the flood level rimof a fixture that is directlyconnected to a sanitary drainage system, and
(b) is extended through the roof when fixtures that are on 3 or more storeysare connected to it.
(3) Fixture drainsfrom fixtures that are listed in Subclauses 7.4.2.1.(1)(d)(iii) to (vi) may be directly connectedto a pipe that,
(a) is terminated to form an air break above the flood level rimof a fixture that is directly connected to a storm drainage system, and
(b) is extended through the roof when fixtures that are on 3 or more storeysare connected to it.
(4) Every waste pipe carrying waste from a device for the display, storage, preparation or processing of food or drink shall be trapped and have a minimum diameter equal to the diameter of the drain outlet from the device.
7.4.3. Location of Fixtures