Why is there a cap on this plumbing vent?
Thanks!
Was it being used ?
No reason to cap it unless not hooked to plumbing anymore ,but may be an issue.
Buck, I hate suspense, now tell us why!! :mrgreen::twisted:
Marcel,
I do not know. From the attic, it is connected to the plumbing system.
Looks like the primary vent, being 3". Was there a basement to intercept the vent in the wall somewhere?
Cap vent, fixtures don’t work.
Like a smaller vent up here in the Winter full of ice. Sink won’t drain.
Possible it was cut off somewhere and mechanical vents being used somewhere.?
Weird.
Maybe some of the other guys will chime in with brain storm solutions. :)
Were there other pluming waste vents and how were the fixtures draining.?
Was there lots of gurgling.?
Show us a bigger roof picture if possible.
How many bathrooms and were they on that side of the house.?
My guess is it is an abandoned vent. Maybe somebody moved a bathroom.
Ok Buck here is my wag…there is a visible tear in the boot, also a bunch of caulk that would not be necessary if the boot were fitting properly…I’m thinking after repeated attempts to repair the leak someone figured capping the line would stop the leaking water…of course it wouldn’t and it sure would impede drainage but as i said just a wag…
Hey Jim, I got a wag too! 
Revisions were made to the plumbing system and an air test had to be performed for the AHJ. When he left, the plumber forgot to go back up on the roof to remove the Jimmy Cap.
How’s that?:mrgreen:
that would work too Marcel…
I noted the tear and the sealant. I asked a roofer the other day about the sealant on plumbing vents. He said he sealed every new flashing he installs.
Thanks!
If there is no other main stack, then this rubber cap needs to be removed.
How did the plumbing inspection go?
All the drains worked, no gurgling, no slow drains. There is a 3 inch stack.
Buck, there has to be another vent if there is nothing wrong with the flushing or sink drains.
If there is none visible, there must be one dumping in the attic possible hidden in the insulation.
They might of done renovations and never exited the vent to the attic and/or the exterior.
Plumbing fixtures just don’t function properly without a vent.
Mysterious indeed. :):shock:
Marcel,
There is another vent, a three inch stack. I deferred the whole mess to a plumber
Good job Buck. 
I would agree.