One side of my bedroom is underground, the other side is ground floor as we are on a hill. On the underground side is stone, then an air gap followed by what is assumed to be plasterboard or something similar.
There are no signs of damp on the wall but the wall is cold and you can smell and feel it is present.
What is the proper procedure? insulate this wall some how? Any help that doesn't include ripping the wall down would be great!