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.

Looking from outside we seem to have an outlet on the outside wall (about 3m
from the bathroom) on each floor but still we are getting smoke fumes from
other flat's bathrooms.

We have an Xpelair extractor which has a flap behind the fan that only
flaps 'outward' thus
preventing air from coming in. We can only smell smoke coming in when the
extractor is on - when it is off there is no problem. The extractor is
sucking air out, but I assume not very efficiently.

My question is, is it the extractor that needs replacing or do I need to put
some sort of backdraft "preventor" behind it? My innitial though is that
the extractor needs replacing since the problem only occurs when the
extractor is on so maybe it is just not powerful enough, and the exhaust
from other fans in the block is coming back in through mine.

Any thoughts?! Any help appreciated.

--
Ant