Shower condensation causing mold in bathroom - what to do?

[dragonfly101]

There are five people in my household, and every after every shower the vapour and condensation in the bathroom is incredible - the colder the weather outside the worse it is. This winter though I've noticed some black mold forming where the exterior wall meets the ceiling. My bathroom has one small window (see photo), the wall above this window get's damp after a shower (you can see my fingermarks in the photo), and after several showers it's dripping. Opening the window to maximum doesn't seem to help much - and I think it might be making it worse by making the wall colder.

Really not sure what to do, apart from enforcing a 'cold showers only' rule on the family. Would adding some kind of fan to vent through the roof help?

 

[foxhole]

Ventilation. Decent extractor fan. Have 7 in my household , no condensation or mold.

 

[dragonfly101]

Thanks, been having a look at different fans on screwfix, I'll probably make a pigs ear of installing it if trying myself, so will get an electrician.

 

[JohnD]

through the roof

through the wall is usually better. If you are thinking of making a hole in the roof it might let the rain in. Unless you are a competent roofer.

There are special "core drills" that are used for cutting a neat round hole through a wall that the duct fits into.

In your case, have it wired so it comes on with the light switch, and runs on for 20 minutes afterwards.

Good quality modern fans can be very quiet and use negligible electricity.

This is a good one
https://www.tlc-direct.co.uk/Products/SLSD100CRZ.html

you can get much cheaper ones, but the bearings wear out and they get noisy so people stop using them, and moan.

Bathroom extractors work best with the door and window closed. They will suck in cool dry air through the gap under the door. Hot air and water vapour are lighter and will rise towards the ceiling where the fan will suck them out.