Damp on internal wall (split from old thread)

[javiercarrillo]

Apologies for reviving an old thread (and I hope you managed to solve your damp issue, jbwilliams).

I think I have a similar problem: the corner of my garage that connects to the frame of a metal door shows what looks like damp at the bottom. It has been like that for a couple of years, without worsening, however I'd like to address it because it's an eyesore.

What surprises me is that the plaster next to the frame does not "feel damp" and the issue is only at the bottom (different to jbwilliams' issue). However I am not even sure if it is plaster (when I knock on it, it feels and sounds solid, whereas when I knock higher on the same wall, it sounds hollow. With that said, the corner bead on that wall is all rusty so I guess it is indeed a damp issue, somehow.

Have any of you seen anything like this and have any advice? Should I try to remove the "plaster" (if it is plaster) and corner bead? Or it is too much for a DIY job? I'm also considering changing that metal door anyway (since it is always cold).

Thanks

 

[JohnD]

Looks to me like the damp is coming from a leak. Is that boxing-in we're looking at? What's inside it?

Is there a void under the floor, or is it concrete? Is it damp?

Stand back and take some wider pics

Show us the other side of the wall please.