Welcome, my name is XXXXX XXXXX I will do my best to help with your issue
Are all the fixtures in the downstairs bathroom used regularly?
No, they are not. I would say once a week on average unless I have guests.
There are basically 2 probable causes for this problem. The most common is when the water in the trap for a little used fixture dries out. When this happens the water seal can no longer hold out the sewer odor. The fix for this one is easy. Just run some water in all the fixtures at least once a week, more often if the air is very dry. The other possible cause is more of a problem.
If you have a broken plumbing vent pipe (usually buried in a wall) it can let sewer odor into the house
Since they are buried in a wall finding this culprit is much more difficult
One other possibility. Do you only smell this when water has been run in a sink?
In that bathroom
Hard to say regarding the sink, as that is the one fixture that DOES get used once or twice a week. The toilet and shower only get used when I have guests about once a year (for a week at a time). That could be it... I just cant recall if the smell comes on after I have run the sink.
My money is on the shower
I can say that the smell does not necessarily come on each time I run the sink.
However, I do notice that any warmer change in the weather around here DOES bring the smell on.
Try running the shower once a week for a couple minutes. That will refill the trap. Not likely the toilet since the water in the bowl would have to evaporate
One other note regarding the shower. A couple times last year I noticed that a bunch of material that looked like it came from my upstairs garbage disposal suddenly popped up through that downstairs shower drain up into the tub.
That sounds like a drain stoppage. Shouldn't be related to this problem.
Is this other bathroom in the basement?
OK. Thanks. XXXXX Any other ideas, or am I good to go?
There is only one bathroom in the basement.
Two bathrooms and the one kitchen are upstairs.
I meant is the problem bathroom in the basement
No sewage smells have ever come from either upstairs bathroom.
Yes, only in the basement bathroom.
Ok, if running the shower doesn't help it's possible the seal on the toilet at the floor might need to be replaced
I have heard that before as well. SOmething about a vent hole needing to be left.
I had a friend who is not a plumber refit the toilet after I had the floors done. Might be it.
Not exactly, if the toilet seal fails normally you would see the leak but since the toilet is on the basement slab the leak could be seeping into the floor unnoticed
try the shower first, it's easiest
I'll try running the shower once a week to start with.
Then have the toilet checked.
Then assume that there is a broken vent pipe somewhere.
SOund about right?
That's the likely progression
easiest to most difficult
BTW, the basement floor is simply polished concrete.
Possible that sewage would leak under that?
There is almost always a gap between the pipe and the flange the toilet bolts to at the floor. A leaky seal can easily seep into that gap
OK. Thanks. I'll go with the progression.