We moved into a new house at the end of 2007. We have been having problems in one of the upstairs bathrooms. When the toilet is flushed, it creates a gurgling noise in the drain of the tub. This is a jack and jill bathroom with the sinks in separate rooms. This was consistent each time the toilet was flushed.

The plumber's first attempt was to add another vent coming from the tub. This seemed to help the problem. However, as soon as he tied it into the existing vent out through the roof, the problem returned.

He than checked the pipes for any blockage and verified everything was in working order. He than tried to use a studor vent on the new vent pipe rather than tying into the existing vent. As soon as he put the studor vent in place, the tub gurgled when tested. However, if he removed the studor vent and left he pipe open into the attic, it seemed to work okay.

It was suggested that we just leave the pipe open, but after researching on the internet, we were adamant that we didn’t want those gases in our attic!

His next attempt was to go under the house and add yet another vent. Each vent seems to help the issue to some degree, however, you can always count on it to fail the flush test first thing in the morning!

Came home from work and found him yet adding another vent. This one on the pipe coming down through the wall. So, this makes three! Sorry to say, but tub gurgled with the morning flush test.

At this point, he was convinced that it had to be the toilet. So, to prove him right or wrong, we bought a new toilet and he installed. He flushed and flushed (hate to see my water bill) and it didn’t gurgle. Told him it had to pass my morning flush test. FAILED AGAIN!

We are both at our wits end and any advice on this would be greatly appreciated. Our plumber has run out of ideas and our builder is getting tired of our phone calls! It has improved immensely but we’re afraid there may be a bigger problem. We built this house as an investment and are afraid this issue might come back and bite us!

When a tub "gurgles" at you it's generally a sign that it's venting,(drawing air) through the trap. This is a venting problem pure and simple.

The plumber's first attempt was to add another vent coming from the tub. This seemed to help the problem. However, as soon as he tied it into the existing vent out through the roof, the problem returned.
He had the right idea but the fact that it failed when he connect it to a existing roof vent would have alerted me to focus on the roof vent itself.

Came home from work and found him yet adding another vent. This one on the pipe coming down through the wall. So, this makes three
If he revented back to the same roof vent he would have the same result as before. So many times we overlook the obvious. I would have started my analysis at the roof vent and worked backward from there. Your plumber sounds like he was lost and just started installing vents hoping it all would just go away. Well it didn't and now where are we?

At this point, he was convinced that it had to be the toilet.
Does the phrase "Hail Mary Pass" sound like it might fit? Your plumber's burning out on the job. Would it be possible for the contractor to bring in a sharp plumber to take a fresh look and see if he can't get to the root of your problem? Good luck and please keep me informed. Tom

Thank you for the prompt response. I failed to mention the third vent was another studor vent so it was not incorporated into the existing vent. He swears the roof vent is fine as when he cut into it to tie in the new vent, he was able to look up in to it and see the clear blue sky and tested air flow in the other direction.

I agree, our plumber is at a lost and is just shooting in the dark. I will follow-up with our Contractor (who has moved out of state and is no longer building!) and see where I can get with him.

One last question if you don't mind, do you think it would be beneficial to take the vent he added from the tub (now in the attic with a studor vent) and take it up through the roof to vent?

One last question if you don't mind, do you think it would be beneficial to take the vent he added from the tub (now in the attic with a studor vent) and take it up through the roof to vent?
I don't see any advantage to running out the roof except a vent through the roof wouldn't be subject to mechanical failure like a AAV.The tub should be wet vented by the lavatory vent so it shouldn't make any difference. ( did he even check the lavatory vent)? Regards, Tom