2nd Floor Sink Feeds into Basement Toilet Vent Pipe

[Brian Bechtel]

Moved into a house this summer and noticed the vent pipe used to vent the basement toilet is also serving as the drain pipe for our second floor bathroom sink. The picture shows the vertical vent pipe/second floor sink drain and the horizontal pipe is the vent pipe for the basement toilet.

Should I be concerned that water will flow down into the toilet vent pipe and create issues?

 

[Paulypfunk]

Yes, it could send enough muck into the vent that it will eventually clog, and branch vents are not easy to clean if that happens. Can you redo the upstairs drain to make it only a drain pipe, then add a new vent for the toilet?

 

[Sponsor]

 

[Terry]

Have you run hot water down the sink to make sure which way the water is going?