Funny smell in bathroom

For the last week or two my g/f has told me that she can smell a faint sewagey/sulfury/poopy odor in my bathroom.

To be clear, this doesn’t seem to be from either of us emitting something nasty when using the bathroom. My sense of smell isn’t that great but I have smelled it once or twice since she called it to my attention.

This morning, g/f claims that she could smell it much more from sink when the warm water was turned on. I couldn’t smell it.

There’s nothing wrong with the toilet (it’s working normally, isn’t clogged or leaking, and I keep it clean) and I keep the shower and sink drains clean on a regular basis. Just to be safe I gave the sink a thorough cleaning yesterday when I found some normal crud builtup in the drain (scrape it out, use baking soda & vinegar, then followup with lots of hot water and either bleach or pinesol to sterilize).

The bathroom is on a solid concrete slab and there’s nothing leaking anywhere. The second bathroom at the other end of the house doesn’t have any such smell and neither do any of the other water faucets in my house. It’s just the one bathroom.

Any ideas what might be causing this? The only thing that leaps to my mind is possibly the wax ring seal under the toilet is not good any more, could that let some smell pass the normal water trap and get into the bathroom?

I occasionally have this happen to my bathroom sink, when I haven’t used it in a day or more and then run a bunch of water down it. I believe it’s because the water in the trap dries up, and then when a bunch of water is run down the drain, the smelly air that’s percolated up into the trap is forced out the drain.

Well that sink and toilet get used every day, and like I said I just gave the sink a pretty thorough nuking, including running plenty of hot water down it.

Just got back from a few hours of shopping and the smell was noticeable. Sprayed some air freshener about, left all the windows open. This would of course become a noticeable problem the day that we’re having her parents and my parents over for dinner. Murphy rears his ugly head…

It might be one of the traps is leaking slowly and letting the water out. As mentioned, that water is what keeps sewer gasses from escaping into the air inside. You should be able to easily check the sink trap, but the toilet and tub ones will probably inaccessible (if you CAN get to them, then check them out, too), and may be leaking down along the drainpipe where you might not notice it. Might be worth getting a plumber to take a look at it, unless you like cutting into walls and ceilings and know how to tape and patch it back up.

WAG… could it be that the vent stack is obstructed in some way? As I said, just a guess that this might cause gasses from the sewer to vent through the drainaige plumbing instead of to the roof.

Another good suggestion, Squee. I second checking that, as well.

Hm, I hadn’t thought about that. Never had to check one, do you know if anything needs to be done aside from climbing up on the roof and seeing if there’s any visible obstruction?

Have you tried taking out the U-bend pipe under the sink and cleaning it out. Our bathroom sink drain was running a little slow a few weeks ago and there was an odor along the lines of the one you describe. My husband put a bucket under the pipe, unscrewed it (plastic pipes) and I heard a not-totally-macho Ewwww screech from him when he saw the rotting mass of ick and stink that had accumulated in the bend. After recovering from the general icky-icky-ickiness of it, he was able to dispose of the offending mass, and reinstall the pipe. The drain runs as it should now, with and does not smell.

You can run a snake down the vent to clear anything out.

If you are on a well, the water itself can occasionally throw off a sulphur smell when first using the water in the morning (often noticed when running water in the sink). My experience is that this does not happen all of the time and some are more sensitive to it than others.

As you mentioned, the toliet wax ring can go bad or a hold down bolt on the toliet break and allow sewage gasses to escape. There will usually be some water leakage too.

Another possibility is rot. Water repeatedly gets to wood structure supporting the toliet, tub or shower and things happen.

I have this problem, too. Haven’t done anything about it, but a friend of mine suggested that it was some interaction between a magnesium rod in the water heater and some bacteria. Apparently getting rid of this rod helps.

It might. But it will also cause your tank to rust out faster–the rod is a sacrificial anode which oxidizes before the tank does. If the magnesium or aluminum rod is causing water odor (they can), there are aluminum/zinc/tin replacement rods that are supposed to help with the odor problem. Activated charcoal filtering or a revese osmosis system can also help, since the odor is apparently caused by a reaction between sulfur in the water and the anode metal.

Thanks for the advice everyone.

Tabula Rosa, I don’t think that it’s the sink trap since I’ve had to clean it out before and while there’s been normal skin/dirt/soap/crud in there it’s never been stinky nasty. That’s why I flush and disinfect the drain periodically. The drain is flowing normally, no backup.

Helix, I’m not on a well, just normal municipal water supply. I’ve never had this problem before which is why I think it’s something out of the ordinary. I am familiar with the sulfury smell that some purification systems can produce, it’s not that. There’s no visible water leakage anywhere and like I said the whole bathroom is built on a solid cement slab.

Tomorrow morning g/f will get pressed into service holding the ladder while I climb up on the roof with gloves, flashlight and snake, we’ll see if that gets the job done.

No one mentioned the over flow, that is the little hole at the top of your sink that allows water to flow out if you have it stopped up. They can get really cruddy and nasty smelling and you will get a whiff of it every time you run water down the drain. Fill your sink to have water overflow into it and then dump a little bleach into it and rinse it afterwards. Also pull your pop up drain out (turn it to the left or right and it should easily be removed) and clean it now and then, as they also get rather nasty with hair and scum build up. The purpose of the s or p trap is to stop the sewer gas from coming back up I seriously doubt anything in it is your problem assuming the water flows down as it should.

Valgard , As a former sewer cleaner I’d say that the vent is almost never clogged. To check it all you have to do is put your ear to it while someone else flushes the toilet. If you hear it loud and clear then it’s fine. Or you could pour a bucket of water down the vent pipe and listen to see if the water drains off.

Plus there’s usually gurgling going on if the vent is clogged.
The wax seal sounds like a good start.

Excellent, I will do that. It was pouring rain and high winds earlier, it’s clearing up now so I can enlist g/f for this. Helped my dad replace the seal on a toilet once, it’s kind of a sucky job but I’m sure I can handle it.

Rikster, I cleaned the overflow as part of cleaning the sink.

We had some nasty stank coming out of one of our hot water heaters once. If it is in fact the hot water heater, you (or your g/f) should be able to smell it by simply running some hot water into a glass, taking it away from the stinky bathroom, and sniffing the water. Our problem was solved by replacing the anode rod.

This also helped us to find a better plumber. The first one said it was a problem with the “anal rod”. We found a new one.

And I eat my words, looks like Rikster was right.

After spending a pleasant hour or two on my roof listening to toilet flushing sounds through the vents and running water down same to make sure that all was clear we were able to narrow down the phantom stink to the sink.

Checked the trap, all clear, no blockage or smell. Removed filter on faucet and ran the water, still got the smell. Removed the entire faucet…still a bit of a smell. At this point I was thinking that somehow the faucet itself had something die inside of it so I removed the whole thing, g/f and I made a run to the hardware store for new hoses and faucet (can you tell I’m getting desperate at this point?).

Came back and tried some more scraping and flushing of the overflow, per suggestion from the manager at the store. After a bit of this, I noticed that there was a sudden increase in flow through the overflow exit (where it feeds into the downspout) and a glob of some vile substance plopped out.

Looks like 50% black crud and 50% booger. “Ick” doesn’t it do it justice. It was like watching a boil get lanced - sudden stream of “bathroom pus” squirted out. The more I flushed (this time with funnel and buckets of hot water) the more came out. Alternating poking with a bit of wire and flushing with water released more and more of this disgusting slop. It stinks. I’ve run literally gallons of hot water down there, targeted cleaning with baking soda and vinegar, boiling water, etc. Dunno if I have most of it but g/f ready to kill me so I have to stop beating on it (luckily have second bathroom). I’ll work on it some more tomorrow night but at this point I am thinking one of two things might be worth it:

  1. Drain cleaner. I hate the stuff and never use it, but I’ve got a bottle. Given that I know exactly where the shit is this might be a case to go for it. Have to somehow block the downspout so it doesn’t all just drain right away.

  2. Replace the sink. Honestly, if a cheap porcelain drop-in bowl sink is a few tens of dollars, it is cheaper than wasting all my time. Again I hate the idea of this but it may come down to how I want to spend my evening.

Do plumbers have a name for this crap? Any favored ways of banishing it?

I got to this thread too late to offer up the sink vent as a possibility (good call, Rikster), but I can say that I’ve run across it many times. It is a buildup of mold and fungus that is pretty much inevitable in a warm, moist and dark space. You got the main problem taken care of when you cleared the vent. Now it will not smell nearly as much. To really disinfect it, plug the vent outlet in the drain and pour in some bleach water, about a 25/75 mixture, and let it stand for 10 to 30 minutes. Let drain and rinse. If you’re concerned about a recurrence, put some bleach water down it once a month or so.

Rikster takes a bow :slight_smile: Any cleanser will do, Top Job or Ajax or bleach and water as Rhubarb said. I just as a point always try to remember to flush a little water down there every time I use the sink. A little PM every day you’ll never have the problem again.
I wounldn’t waste money on a new sink as you have the problem licked now. hum maybe I shouldn’t have used the word licked talking about that puss blob. lol