Bathroom smells, not our fault!

November 27, 2020 10:15 AM

What is wrong with our bathroom sink drain? Can we fix it?

There has been a somewhat sewage-y smell in our bathroom since we moved into our apartment a month and a bit ago. It comes and goes, but today we decided to try and figure out exactly what the problem was. After trying to clean under the shower and sink, we saw the following:

Finely crafted imgur link

The white hose coming out of the trap (first photo) runs down into a pipe in the floor, but it doesn't really seem to have anything that seals it: you can slide that pipe in and out without any real resistance, and you can completely remove it (and we cleaned it out thoroughly).

It seems like there should be something that seals the pipe to base, but we don't know what piece goes there.

What is the name of the thing that we put there to seal these things together? Assuming that is a thing that is missing, we are hoping to avoid having to call a plumber and do this ourselves.

(In case it is relevant, we live in Sweden)

posted by vernondalhart to Home & Garden (13 answers total)

I'm no plumbing expert, so take this with a grain of salt, but - that bit that hangs below the level of the white hose coming out the side seems like a prime spot for stinky bacteria to thrive in. You could try dumping a fair amount of baking soda (say, 3 to 5 tablespoons at least) down the sink drain, chase it with about half a cup of white (distilled) vinegar, wait until the foam dies down, then repeat the vinegar a few times until no more foam results.

I've also been told that such smells can result from a blocked plumbing vent. That would be something you'd need to bring up with your apartment supervisor/owner.
posted by Greg_Ace at 10:39 AM on November 27, 2020

What is under that plastic cap on the floor?
posted by mhoye at 10:49 AM on November 27, 2020

Response by poster: mhoye: To be honest, nothing of note. It can slide up and down, but it doesn't really seem to do much, and it definitely doesn't seal anything.
posted by vernondalhart at 10:52 AM on November 27, 2020

Just how accessible is this? This looks like the sort of thing a small hacksaw, some PVC cement, and an extensive selection of PVC pipe fittings from your local hardware store could solve as a shadetree plumber, even if your landlord isn't interested. That said, they might have a reason for not having fixed it. I mean, yanking the corrugated tube out of the floor drain makes it super easy to snake out blockages, for example. On the other hand, this corrugated plumbing is a cheap and nasty solution to buying the right fittings, with the emphasis on both cheap _and_ nasty.

And it's possible that a natural trap has developed somewhere in your waste side plumbing that's causing sewer gas to preferentially come up through your drains rather than out your attic vent. Properly sealed (i.e. not with just a pipe shoved into another pipe), the under sink trap will stop the odor from coming through.

I mean, I'd start with an all new trap under the sink, unless if that's a normal compression fitting to the corrugated pipe, then just keep everything sloped downhill enough to drain properly until I got to the floor drain. Dry fit everything at first, then glue it up segment by segment until it's permanently installed.
posted by Kyol at 10:58 AM on November 27, 2020 [1 favorite]

I'm unfamiliar with Swedish plumbing practices, but I don't see how the thing you're calling a trap can work as a trap. Do you not have S and P traps?
posted by jon1270 at 11:00 AM on November 27, 2020 [2 favorites]

Ah, a bottle trap. I should've Googled before commenting.
posted by jon1270 at 11:04 AM on November 27, 2020

Response by poster: jon1270: Yeah, it seems to be a bottle trap. But since the outflow has a lack of seal behind it (the other end of the corrugated pipe), doesn't that allow for gas to back up? That's what we are guessing the problem that we hope to fix is...
posted by vernondalhart at 11:06 AM on November 27, 2020

I agree. I think a proper fix will involve gluing a fitting to the rigid pipe coming up from the floor, and replacing the corrugated part with rigid fittings. Kyol is on the right track.
posted by jon1270 at 11:17 AM on November 27, 2020

I'd just use some silicone caulk around that fitting, as you're just trying to seal it to gas, not fully replumb. Should be quick, easy, cheap and pretty easy to take apart if it doesn't help.
posted by so fucking future at 11:23 AM on November 27, 2020

Your drain smells because it is missing a p-trap. The job of a p trap is to maintain a small reservoir of water in between the actual drain, which sends back or up the smells, and the bottom of your sink. The water separates the air spaces. It should be fairly easy to install one there, though probably a job for someone with experience.
posted by Dashy at 12:13 PM on November 27, 2020

You may have a broken bottle trap, as the photo at this link matches what you have posted and the description says the first sign is a bad smell.
posted by tiamat at 12:43 PM on November 27, 2020 [1 favorite]

I would take these photos to my local small hardware store and ask what they would suggest. Often the staff at such stores will be able to point you right to the parts you need.
posted by yohko at 5:10 PM on November 27, 2020 [2 favorites]

Yohko's advice matches mine, when it comes to home repairs I haven't done before. When you're not sure what to do and Google isn't helping you, go to your local contractor's store, find the oldest, grizzliest looking person in the section you want, show them the pictures and ask them what you need.
posted by mhoye at 9:00 AM on November 28, 2020