Solving condensation problems.

Wall had a serious condensation problem which resulted in efflorescence hydroscopic salt, found in sand. The mortar gets damp and the salt rots through the plaster. To cure the problem I hacked the plaster off and thermal boarded the wall to create a cavity and insulate the room. I are also fitting a new vent,so the room gets adequate ventilation,thermal protection and a cavity to help the house breath.all finished with 2 coats of skim.