DWV - plugged??

[Kburkhal]

Our home was built in '99 and not particularly well by my standards. I gutted and remodeled one bathroom so far and replaced the toilets in the other too (Toto's of course). The old toilets were likely the original contractor grade and plugged often.

In our other bathrooms, the sink or tub make a lot of noise when the toilet is flushed and it seems to be getting more pronounced with the new toilets. I have been in the attic multiple times and I know there is PVC vent lines up there but I have not traced them back as a drain waste vent vs bathroom fan vents. In the remodeled bath, I put in a sure-vent when replumbing the sink - no apparent noise reported by anyone. My primary concern is the master bath upstairs. I can live with the 1/2 bath downstairs.

Is the noise an indication of a blockage somewhere in the drain waste vents? The new toilets flush fine and no clogs. Could this be a result of using low-flush toilets vs the old full-flush contractor grade? Is there any easy way to troubleshoot and/or fix the issue?

 

[Jeff H Young]

Remodeled bath room works fine. 1/2 bath downstairs you can live with meaning its got a problem but not concerned about.
Then there are " other bathrooms" that make noise in sink or tub, how many bath rooms ? I count at least 3 1/2 bath?
Remodel has different meanings but during that work perhaps all the other vents were capped off for testing. might have filled stack out roof and capped off the old vents that were existing and never reconnected
Generally noise as you say is a blockage but all the drains and nothing draining slow makes doubt

 

[Sponsor]

 

[Kburkhal]

Remodeled bath room works fine. 1/2 bath downstairs you can live with meaning its got a problem but not concerned about.
Then there are " other bathrooms" that make noise in sink or tub, how many bath rooms ? I count at least 3 1/2 bath?
Remodel has differant meanings but during that work perhaps all the other vents were capped off for testing. might have filled stack out roof and capped off the old vents that were existing and never reconnected
Generaly noise as you say is a blockage but all the drains and nothing draining slow makes doubt

House has 2.5 baths. The upstairs full bath remodel included new toilet, new floor, new bath/shower (replaced shower valve, installed shut off valves, and new plumbing from valve to shower head, snaked the drain piping due to previous slow drain), and new vanity (had to replumb the drain pipe due to vanity size - in doing so, added a sure-vent). I was present during the whole remodel - nothing was done to the existing vent stacks. The downstairs 1/2 bath just has a new toilet for now - it does make sound when toilet is flushed but as obnoxious as the master bath.

I have thought about checking the stack on the roof to be sure it is not plugged but 2 stories up on a high pitch roof is not my first choice....

we never use the tub in the master bath, is there any value in dropping a 5 gallon bucket of water into it? maybe there is an air pocket somewhere and the draining the tub may "suction" the pocket? I'm grabbing at straws on that one...

 

[Tuttles Revenge]

The flushing of a toilet shouldn't affect other fixtures if everything is plumbed correctly. The water rushing from the toilet shouldn't be able to create vacuum or pressure against the trap seal of another fixture enough that you would hear it. While generally when that does happen its because of a blockage in the line that prevents free air flow.

I had a newly remodeled project do something similar where the tub wouldn't drain but the toilet would flush. Long story short, I ended up mocking up the horizontal wet vented plumbing in our parking lot and could not get the system to fail no matter how badly i blocked or flat eliminated the venting. It wasn't until I blocked the drain that I got similar results. With that info I went back to the jobsite and found a clean seal test balloon still installed in the test tee. Once removed it all worked great.

I also have another client who can hear the AAV open on one of his bathrooms, but not another. He suspects that it was a series of offsets that allows more suction against the valve than a more "efficient' flow of the other bathroom.

If your vents were filled with water from being plugged.. not likely, but it does happen when vents get capped improperly. You can go up in the attic and perform a Knock Test. Unfilled plastic pipe will have a different sound and feel than a pipe filled with water. White PVC vs ABS will have slightly different sounds, but feel more dense when you knock.

 

[Jeff H Young]

kburkhal well no reason not to experiment the 5 gallons or fill tub and dump see what happens. Whatever checking you can do and learn about the system. Tuttles revenge brings some insight knocking on plastic you can tell if empty or holding water by sound.
never a stoppage? slow drain? when did it start? sure vent why add that? didn't the lav have a vent.
might be an easy fix after figuring out the cause leg work investigation

 

[Kburkhal]

filling the tub and draining did not help and even seems to make the issue worse. Next step is to get into the attic and knock on some pipe and/or use a bright flashlight to look for any blockage above the master bath. The sink drains slowly and we periodically run drano through it. I may tear apart the p-trap and clean it out, assuming it has build up in it. The tub and the shower drain fine.