We recently had a plumbing issue. A toilet overflowed, covering the bathroom with dirty water. We fixed the clog, removed the overflowed water, and cleaned the bathroom thoroughly with bleach. The only residual damage we can see is that the water against the door made the bottom of the bathroom door soggy, and some of that wood has shaved off with closing of the door. I've smelled the door, though, and don't think that's where the smell is coming from.

When we come home from work, the entire apartment has a musty smell. We open the windows, and within an hour or so the smell is gone. Sometimes I think I can still smell it in the bathroom, though, which is why I think it might be originating there.

I've put a bleach flush tablet in the tank and cleaned the toilet again with bleach.

Any ideas? It might be useful to know that both our kitchen and bathroom sinks regularly fill up via the drains with soapy water that we assume is coming from the laundry room. We are on the ground floor or a large, old building, directly over the laundry and boiler. We also occasionally smell things through our gas stove--I thought we had a gas leak once, but it turned out that they had painted in the basement below us, and the pilot lights were burning off the paint smell (or something like that).

Thanks for your help!

Dirty water made it's way under the floor along the base of the walls, usually near the toilet and tub or shower, where weight changes mostly occur and so caulking is used. Go down in the basement and investigate. Fill a spray bottle with bleach and cover your head and face with old tee shirts.

Aim a big fan across the floor for at least 3 days, after bleaching all around the bathroom edges.

Tell the landlord in writing(if you aren't the owner) about the poor drainage from the laundry, because sooner or later it will really back up.