Just bought a house built in the 50's with upgrades to bathrooms in early 90's. I have an occasional sewer-type odor in one bedroom/bathroom area. I went into the crawlspace under this bathroom and found a vertical uncapped pipe with a slanted cut on top. I assume some kind of vent? It is attached to the drain pipe after where the shower and toilet and before where the sink drains come in. This all then drains to an ejector pump, as the bathroom is below street/sewer level. What is the purpose of this uncapped pipe? I imagine that is the source of my odor? Why is the odor only sporadic? Should I do something different with this pipe? Cap it? Thanks.

There should be no open "vent" pipe under the house. It might have been the old drain for the tub/shower and whoever did the bath remodel forgot to cap it. Cut the pipe square and put a cap on it.

but then again it might be a vent??
so, as steve says, it may be an unused drain and must be capped. if it is a vent it must be run up thru the roof or into a vent stack somewhere.
the reason it smells sometimes may have to do with the ejector going on and off ???

the Lord Packy has spoken

Heed His Word !

seriously

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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

Thanks to all.
Capped it and smell seems to have dissipated.
Other drains are vented through the roof so all seems good.



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