I am hoping some smart person can help me with ideas for identifying odor problems in my master bathroom.
There are two subtle odors involved, one comes from near the two sinks, the other from near the toilet. Both are subtle. The one from near the sinks is a kind of fermenting smell. The one from around the toilet is a sharp smell. They do not smell like a sewer odor. Both odors are stronger when the weather gets cooler and damp, and if one of the windows is open a bit.
Sinks first: it doesn't appear to be coming from the drain or the overflow. I've cleaned both with several types of chemicals and cleaners. The p-traps function correctly.
The smell from near the toilet could be from the bowl, but it is hard to pinpoint. We had it reseated last year, and there's a silicon seal around the base that is intact.
I tested the all the roof vents using peppermint oil. No peppermint smell came into the bathroom. I've checked the crawlspace under the bathroom. There is no sign of leaks, and no unusual odors are present there. I checked outside the house. There's a compost pile about 30 feet away, the odor is not coming from there. Nor can I find any other likely source outside the house. Ive also checked the attic above the bedroom. There's no unusual odor up there either.
The bathroom is new construction, completed about two years ago.