Anteateruk wrote:

Hi,

I live in a flat with an internal bathroom. It has an extractor fan that
seems to be able to prevent the bathroom from steaming up very well, but
somehow seems to suck in fumes from other bathrooms in the same block.


Well, if it is, the chances are that you have a path to the other rooms
via some unseen pipe run or somesuch. The fan must be sxtractingf, so
where is the air getting IN to the bathroom?

You are supposed to have e.g. a hole in the door, or a gap underneath,
to let air in from the rest of your property. If it ain't there, the air
will come from wherever it can. Possibly over a ceiling void, through
holes punched in walls and floors for pipes etc etc.

A few weeks ago, there ws this terrible smell in a room with and
extractor...traced it to a giant puppy turd miles away up the hall. Yup.
Thats how far the air had moved towards te extractor..