Waste Stack Discharge Receipt

[RJ539]

Terry,

With reference to the paragraph cited below, I am confused with the third (3rd) sentence found in Para. 913.2 of the 2018 IPC: Is it's intent to prevent someone from locating a toilet flange directly on top of the waste stack?

If not, I'm at a loss to understand how one directs the discharge of water closets and urinals to the building drain.

Can you please comment as to the meaning and intention of this sentence?

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2018 International Plumbing Code
Chapter 9 Vents

Para. 913.2

The waste stack shall be vertical, and both horizontal and vertical offsets shall be prohibited between the lowest fixture drain connection and the highest fixture drain connection. Fixture drains shall connect separately to the waste stack. The stack shall not receive the discharge of water closets or urinals.
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Thank you kindly in advance for any words of wisdom,

 

[Reach4]

https://wabo.memberclicks.net/assets/pdfs/Plumbing_Venting_Brochure_2018.pdf

I am not sure, but I suspect that would be when you are venting with a stack as in the pictures on page 3. "special Waste Stack Venting system.". I could be wrong.

 

[Sponsor]

 

[RJ539]

https://wabo.memberclicks.net/assets/pdfs/Plumbing_Venting_Brochure_2018.pdf

I am not sure, but I suspect that would be when you are venting with a stack as in the pictures on page 3. "special Waste Stack Venting system.". I could be wrong.

Reach4, thanks for your input: I suspect you're correct. It would have been infinitely more clear had Para. 913.2 of the 2018 IPC written "vent stack" vs. "stack" in that third sentence.

Since posting this, I have come to realize that WA has adopted the UPC, not the IPC, so I will repost my basic question, "Is there any provision within the UPC venting requirements that would allow me to reduce the my 3" dia. soil stack down to a 2" dia. vent stack extension (thru the roof), short of adding a third 2" dia. vent stack (for a total of 3) to adequately vent my 2-story soil stack which drains into a 4" dia. septic line at the building exit.

https://wabo.memberclicks.net/assets/pdfs/Plumbing_Venting_Brochure_2018.pdf