Ceiling damp bridging from roof timber

[MidsTW]

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3 small patches of damp showing through the ceiling paper. This has only recently happened. I had a look in the attic and it seems to be the area where the rafter meets the joist. The house is 1950's with no felt in the roof. The rafter get damp from time to time but drya eventually due to the good air movement.

Question is... What can I do to limit the damp bridging into the ceiling plaster?

 

[MidsTW]

Not sure if this post is in the best place... Had no replies which is unusual.

I have taken some better pictures....

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I know that if the source isn't stopped then it will come back. There is 100mm of insulation in that area, but it seems that at some point the surface is getting cool and condensation is forming on the roof side of the ceiling.

Shall I paint over it to see if it comes back?

Any advice greatly appreciated