(1)
A vent stack or stack vent shall be sized in accordance with Table 7.5.8.4. based on
(a)
the length of the vent stack or stack vent, and
(b)
the total hydraulic load that is drained to the lowest section of a stack served by the vent pipe, plus any additional vent loads connected to the vent stack or stack vent.
(2)
For the purposes of Table 7.5.8.4., the length of a stack vent or vent stack shall be its developed length from its lower end to open air.
(3)
The minimum nominal pipe size of a vent stack or stack vent shall be one-half the NPS of the stack at its base.
(4)
A stack vent serving a wet vent stack that is over 4 storeys high shall extend the full size of the wet vent to open air.
(5)
Sanitary building drains shall be provided with at least one vent that is not less than NPS 3.
Table 7.5.8.4. Size and Developed Length of Stack Vents and Vent Stacks(1)
Forming Part of Sentences 7.5.8.4.(1) and (2)
(1) NP = not permitted and NL = not limited.
(2) Stacks shall be sized using Table 7.4.10.6.-A.