shower room ceiling flaking paint

[bsffamily]

hi all,
firstly sorry for almost duplicating a previous post but the circumstances sound a little different so thought i would ask advice as to best remedy.
A few months ago I was asked to paint a a friends bathroom , the ceiling was paint was flaking so I sanded off what I could and applied a coat of damp stop thinking that was the problem then painted over with emulsion.
unfortunatly its looking just as bad as before and there are cracks along the plaster board panels where the paint is beginning to flake. How can I get this sorted as I feel I've let my friends down. can i rake out along the cracks fill and paint or should I be doing something else to them, and whats the best way to ensure no more flaking paint.The ceiling was plastered over ten years ago and the owner doesnt think theres been any major leaks in roof in that time. There isnt a fan in the shower room could this be causing the problem?
any advice would be gratefully recieved
thanks
simon

 

[bsffamily]

hi guys,
would be great to get some feedback as i have a bit of time off work and can go back and remedy.
thanks for your time
simon

 

[Robbie uk]

Poor ventilation in any bathroom will eventually cause problems. The moisture has to go somewhere! A vent above the shower with a timer to keep it running after the light has been switched off is best. The ceiling needs to be thoroghly rubbed down and any mould patches treated with a good antifungal soloution. A good strong bleach solution can be just as good. The crack needs to be made bigger to in order to fill it properly and then rubbed down. I would treat the ceiling to a coat of oil based undercoat first before applying any emulsion.