Yes that’s right. It’s just one set of bricks, no cavity. Do you think an air brick would help in this case? Does this explain the external wet wall too?
I have been trying to figure this out for quite a while. I have had an issue where my internal wall to a cupboard is quite damp but no other external walls are.
Underneath the skirting board seems to be crumbling and there are quite deep holes in the wall.
It looks like the outside of the wall...