Paint Reaction above Bay Window

[hontoir]

It was recently noticed that the small section of paintwork at the far end ‘looked damp’.. it was significantly darker than the surrounding paint.. and the whole wall feels quite cold.

This photograph was taken after using a dehumidifier for the day.

To provide a bit of context, this is the outside view.

Any thoughts would be fantastic.

 

[^woody^]

Roof leak from rotten felt at the eaves

 

[hontoir]

Roof leak from rotten felt at the eaves

Thank you for your reply, the properly was constructed in the 1930s? and does not have any felt. It has been fitted with the plastic trays, that tuck under and over into the guttering.

 

[^woody^]

The marks above the longer section of frames are similar to condensation but it's hard to make out from that image.

The stain above the short frame is more indicative of a water stain than a condensation stain, and if so would relate to roof - not necessarily directly above.