Hello,

We have an odor in our master bath that's like old gym clothes. It seems to come from the two sinks. When the bathroom is closed up, it takes a few hours for the odor to build up, and it gets worse when the weather is cool and damp.

I've flushed the overflow and the drain with chlorine bleach, baking soda and vinegar, and toilet bowl cleaners.These help for a day or so, then the odor returns. I have tried cleaning out the p-traps, which appear to be functioning properly. I've tested the plumbing vents for leaks, none found. I've checked in the crawlspace for leaks and odors there, and in the attic, but found nothing unusual. This is part of a new addition built in 2013. People have suggested testing the water, but no other part of the house has this problem.

Any suggestions for what else I can try? The odor is driving us nuts.

Thanks,

Greg

Greg, July 2016

Check if your sink drains are linked with the toilet soil pipe within the bathroom if they are it could be, when flushing the toilet this will drag out the water within the sink traps leaving them open to soil smells. to test this put some water down the sinks before you go out and see if the smell goes

Rod, July 2016

If the drain is actually blocked then as water is poured into it air pressure my build up and vent back into the sinks in your bathroom. Yet another guess.

An afterthought..., July 2016

Consider that there may be a direct connection that avoids any P Trap (S Bend) between the bathroom and the main foul-water drain.

This happens in my house when our outside drain blocks - foul water does not drain away as it should - we smell it first in the washing machine.

Unblocking the drain makes the smell go away.

Good Luck..., July 2016