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new construction house, kids toilet has sewer smell in the morn

Posted by srg215 (My Page) on
Mon, Oct 11, 10 at 22:33

every morning the kids bathroom where the toilet is has a smell like a sewer. there's no leak and all the drains/fixtures are used frequently in that bathroom. what could be causing the smell? i have a call into the plumber, and he's coming here in a couple of days, but he seems stumped as to why this would happen.

Follow-Up Postings:

RE: new construction house, kids toilet has sewer smell in the mo

Sounds like a blocked or plugged stack on the roof. Not too unusual in new construction. Builders have been known to dump lunch bags, chunks of plaster anywhere it is convenient, not to say it is always done on purpose. Also birds could have built a nest. Anything is possible.
One clue is if the toilet flushes slowly.

RE: new construction house, kids toilet has sewer smell in the mo

Pursuing the logic of the above, using "vent blockage" as a core problem, it will manifest itself as a sometimes-open drain letting sewer air into the house. One of the drain holes is letting sewer air into that bathroom at night. A drain has a P trap to prevent this. Thus, one of the P traps is being "siphoned" or emptied. Tape shut one of the drains. Use masking tape. See if that one is the one letting sewer gas in at night. Try again with another drain. Repeat. If the only drain hole is the bathroom sink, you only have one drain to stopper, to try this. The seal must be perfect. Use tape. In the morning when you take the tape off, the P trap will still have its water in it so you will not smell gas there even if you try real hard. Once you have done this testing, it will confirm to you what the problem really IS. This is valuable knowledge. It enables you and your plumber to know clearly what to do next. Report your findings and await further instructions.

RE: new construction house, kids toilet has sewer smell in the mo

If the wax ring is not sealed to the closet flange, could sewer gas be entering from that end? Picture this scenario: A tiled floor with a finish height higher than the flange and the bottom of the toilet is not caulked. The wax ring may be directing the waste into the pipe without leaking, but it may not be making an air tight seal.

Just a wild idea.

RE: new construction house, kids toilet has sewer smell in the mo

Have your plumber do a smoke test.

It will pinpoint with certainty where the sewer gas is entering the house.

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