Damp in corner of bedroom

[steve001]

I have a wet / damp patch in the corner of an upstairs bedroom. it is on the exterior corner of the room and i have moisture running down the wall. I have checked in the loft above the room and there are no visible signs of a leak and its all dry up there. The guttering outside is cleared regularly and is in good order. What could be causing this problem?

[welsh brickie]

could be a number of things,a rip in the underfelt, a cracked tile or slate further up the roof,an exterior crack.You may have to remove some tiles to inspect.