I have two upstairs toilets (back to back in separate bathrooms) that have been backing up every two weeks for a few months now. The plumbers and rooters can't seem to figure out what the problem is.

Initially, the thought was that using flushable wipes was the problem. The rooter cleared the clog, tv'd the line, and found nothing (no root problem, no debris hanging on somewhere in the line - nothing). Problem solved, right?

Well, two weeks later, the toilets clogged again. No continued use of the wipes. Again, drain cleared, tv'd, and nothing found evidencing the basis for the clog.

Wouldn't you know it - two weeks later, the toilets clog, AGAIN. This time a new rooter comes out, clears the clog, and can't figure out what the problem was.

The main floor toilet only clogged during one of these episodes. Today, the two upstairs toilets clogged again.

For background, one of the back to back toilets was off its base for a few weeks due to a remodel. A new toilet has since been installed there, and it is still backing up.

The last couple of clogs, the toilet seems to be working fine, then suddenly, after one flush, it's plugged. There doesn't seems to be any warning.

Any ideas on why the toilets would continually clog, despite being cleared out every two weeks? Much thanks!!

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    Did you try to unclog the toilet with a plunger first? In 39 years at our tract house I have never had to call a plumber to unclog a toilet. Due to being on a high fiber diet I have had regular clogs in the toilet I use, but I can always unclog with a plunger. Note that the way a plunger is to be used is to give a soft to medium push and a vigorous pull. This loosens and breaks up the clog. Squirrels have chewed off the tops of the lead flashing around sewer roof vents. It could be that lead rings have dropped into the house sewer laterals under the slab. Commented Jul 18, 2017 at 16:11
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    So if we has a problem with clogs that wouldn't respond to use of a plunger, I would suspect lead rings jammed in the line. Commented Jul 18, 2017 at 16:17

1 Answer 1


Is everything properly vented? A stopped up vent would be something above the toilets that could cause enough back-pressure to cause a clog. Check the vent on the roof.

How old is the house? If you're dealing with something old, you could have a drum trap or some other kludge that could be causing funny effects like repeated clogs. Furthermore, the house settling could have caused the plumbing to lose the proper pitch. Improper pitch would mean things wouldn't drain properly, and you'd get clogs.

Do you have a septic system, cesspool, or sewers? If it's sewers you might have a problem with back pressure from them stopping things up.

It could be a check valve that isn't opening (possibly due to back pressure from the sewers mentioned above).

Do you have young children? If they put something down the line that they weren't supposed to and it's deep enough that the TVing doesn't catch it, that could be a cause.

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