Plumbing Problem: toilet backflow
I bought last year a two-unit row house with a newly renovated downstairs unit, including bathroom. In my own recent renovation of the upstairs unit, my contractor gutted the bathroom to the wall studs and installed new pipes and electric, including a pipe vent in the wall behind the sink. The problem is that when…
I bought last year a two-unit row house with a newly renovated downstairs unit, including bathroom. In my own recent renovation of the upstairs unit, my contractor gutted the bathroom to the wall studs and installed new pipes and electric, including a pipe vent in the wall behind the sink.
The problem is that when the toilet in the upstairs unit is flushed, water gurgles and splashes out of the downstairs toilet. It soaks the underside of the lid, and spills onto the floor if the lid isn’t down. It could be a nasty surprise to someone seated on the downstairs toilet, and indeed is a bit scary just to see it happen.
I did not test this before the upstairs renovations started, so I don’t know if this happened with the old upstairs toilet and pipes. My contractor thinks the issue is with the renovation that was done in the downstairs unit – that there isn’t proper pipe venting and air pressure in the pipes. He thinks he might be able to vent the pipe from the basement, but hasn’t spent much time yet investigating. Does this sound reasonable? Has anyone had a problem like this before? How big of an effort might it be to fix?
I was redoing my up stairs bathroom in a split level house. I had a plumber come over and he said I need vent for my shower and sink drain pipes. I currently only have one for my toilet. Is this correct?
Thanks for your comments.
The toilet on the lower floor flushes fine. In fact, everything in the house seems to drain fine: sinks, tubs, toilets (with the exception of the air problem from the upper toilet).
When you say there may be a problem with the way the pipes are configured, could you be more specific?
I opened up a new wall on the upper floor, and verified that there is a vent on the toilet pipe there. Additionally, that toilet is adjacent to a new laundry room. The drains from the toilet and the laundry both go into the same waste pipe. When I flush that upper toilet, I can feel air come out of the drain of the laundry, so it appears that that toilet is doubly-vented. Could this be part of the problem?
Any other thoughts? thanks!
I bow before master plumber’s wisdom. It does sound as if the pressure of the flushed water is blowing the trap water in the lower toilet. Maybe there is a problem with the vent stack going to the roof. Otherwise maybe the lower floor toilet has been placed a long distance from the main stack or/and is not vented past the upper toilet? What happens to the other fixtures in the room like the sink, and bathtub? I always thought that the venting should run parallel to the waste making sure that the vent was above all other fixtures before it reconnected to the main stack going through your roof. On little homes, anyway. I would send for some of those x-ray glasses you could order through BOYS LIFE magazine….if you don’t have pictures.
What happens when you flush the toilet on the lower floor (the one that water splashes out of)?
Sight unseen, if that one flushes fine, you have a problem with the way the pipes are configured.
Venting, or lack of venting, won’t create the condition you’re describing until you reach around ten stories in height. That’s why we use something called “relief vents” on tall buildings.
My thoughts are you have a blocked drain but it would be really helpful if you had some “during” pictures of the renovation.
Let this be a lesson to everyone doing work on their home! Take pictures of EVERYTHING!
Good luck.