shared vent?

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shaken-n-stirred

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If I have a shower upstream of a large soaking tub can I share the vent?

I would run the drain from the shower through a P-trap (of course) then over three or four feet to a vertical vent, continue the drain on another foot or two and pick up the trap from the tub. It would seem to me that would work fine.

I guess the one or two feet of drain from the vertical vent to where the tub trap is pick-up would be a wet vented section (?).

Jurisdiction: Idaho
 
Sorry I do not know how to make a drawing.

But....

Shower and separate soaking tub are on the same floor.
Therefore there would not be a WET vertical vent anywhere.

So, you have a shower, with a drain and P-Trap. So far so good.
That drain line would run horizontally from the drain in the shower over say three feet to a point under a wall. (Pretty obvious). In that wall would be the vertical vent.

The drain would continue on a couple of feet and pick up the horizontal drain from the soaking tub. Therefore, can the forementioned vent be considered a legal vent for the tub. THe issue here would or could be that the part of the drain between where the tub drain enters the "main" drain back to the vent would be WET (as I understand it, could be wrong, please correct me).

Seems like that would be ok. In Idaho? if anyone knows?
 
I believe what you are describing is a Combination Waste & Vent, not a Wet Vent.
 
Nice drawing! Thank you so much.

I don't think I need a 3 inch pipe but that would be ok if required.

I don't think there is a difference between a "wet vent" and a "waste / vent combo" as you suggest. I am by no means an expert so would love to learn the difference if any.

Also hope some one can chime in for more clarification as to legality of the drawing.

The issue is very confusing, as I know you can vent more or less as described if the upstream fixture is a toilet and the second fixture a lav! Pretty share about that. So why not a shower and tub? Then again, never ask why with codes, right? LOL

Thanks everyone. hope for more clarification.
 
Confusing since you are CITING a section of code referring to VERTICAL WET vents of which I would have none.

???

At any rate, it may be far easier to just run a vent off the trap arm of the tub and revent it (if that is the correct term) into the shower vent. IF that is the case does the horiziontal part of the tub vent need to come off the top of the trap arm (or some angle rising from the trap arm) or can it run at the same level (or horizontally) as the tub trap arm?

Thanks for the learning session.
 
Nice drawing! Thank you so much.

.

I don't see any drawings here so I made one. I think this is what you are describing.

I should get a newer UPC. :eek: I may be mistaken about the 3" section on the horizontal.

My book says WET VENTING is limited to vertical drainage piping . . . blah blah blah

Scan-150111-0001a.jpg
 
Last edited:
Hmm? Don't know what happened to the guy's drawing.

Anyway, thanks for your input.

I think in this case it will not be that hard to run a vent off the tub trap arm and back to tie into (revent? term?) the shower vent.

The one question I still have is: does my horizontal section of my vent off the tub trap arm need to come off the top of the trap arm or can I run it flat off to the side for a distance?
 

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