Cause of diagonal damp line

[Jimboted]

Hi all,

I've attached a few pictures of a damp line that has appeared in out loft room. It bled through in the course of heavy wind and rain a few weeks ago, but there is ample evidence of the wall having had issues with damp before.

The house is med terrace. The damp itself roughly follows the angle and height of next door's roof - their house is stepped down from ours.

Having previously done work further along the wall (unrelated to damp) I can confirm that it's been plastered over at least five times, with lime, then gypsum, then two layers of plasterboard and another layer of gypsum.


We've had four roofers round to look at it and every one has suggested a different cause and remedy, which doesn't exactly fill me with confidence.

Has anyone has experienced a similar issue in a loft room? Can you offer any suggestions as to what the issue may be?

Thanks,


James

 

[HERTS P&D]

You would need pictures from the outside.

What did each roofer say the problem was?

Andy

 

[Jimboted]

Hi Andy,

I'm away from the house for a few days, but will get some pictures of the exterior up when I'm back.

One said it's the flashing on the chimney on our side, one said it's the felting in our side, one said it was the render on the neighbourvs side, and one said it just needs painting with damp seal and replastering.

Thanks,


James