Why Important
What to look for
How to fix
Concealment of damp areas is not recommended, but may occasionally be acceptable if the enclosed space is ventilated. A plasterboard lining on battens is the simplest method of concealment, but all battens must be pressure impregnated with a non-staining, inodorous preservative and both the wall surface and the back of the lining should be treated with fungicide.
Alternatively, a barrier, such as corrugated pitch or bitumen lathing, can be fixed to the stonework and plastered over; in this case, the undercoat should be 1:1% browning plaster to clean sand, which will not shrink on drying.
Re-plastering with a suitable plaster (as all specialist companies do) also hides the signs of damp (and failed damp-proofing systems!).