Mould on bedroom ceiling

ljonski

Background . Lived in property 15 years never had any problems with mould. Flat downstairs and at back do but on first and second floor ive never had any problems.
Although bathroom is in next room , skylight is generally open as is skylight in bedroom , so condensation is not too blame.

The bedroom gets heated up for 5- 10 mins when GCH is switched on but leave rad on * setting , so no rad switches itself down to minimum very quickly.

I noticed mould on the ceiling which i wiped away yesterday.It runs down the middle of the ceiling where the curve meets the straight of the ceiling.

i think immediately above is the roof as the insulation is in the loft through the little cubby hole where the wall meets the sloping roof.



Although it is definitely mould , i am led to believe that the spores find their way to the coldest or dampest part they can get to. If this is the case, am i looking at a small leak in the roof causing the mould?

Tia

http://s1382.photobucket.com/

WestonDave

Not entirely convinced by your "condensation is not to blame" - the position hints at a cold joint so I'd firstly test for condensation vs outside damp. Simple to do - dry the ceiling where the mould occurs and stick a piece of kitchen foil over it so that it forms a seal, and the foil is touching the ceiling all over. Leave it overnight. In the morning if the foil is wet/moist room side then its condensation, if its wet ceiling side then its damp coming from the loft etc. Then you can start poking about looking for a leak or other issues.