[bigchicken]

Yes Womble I have come across this before remove skirting and clean away any obstruction there should be a gap of no less than an inch but move would do no harm. The gap serves two purposes air flow and a place for any fallen mortar etc to go.

[mart6]

You could try a foil backed plasterboard dont  plasterboard board to the floor,  leave a 2 inch air gap at bottom.
Even if you plaster a wall leave 2-3 inch gap at bottom
Then use upvc skirting boards
(Bewary with rock wool idea put a piece in water it acts like a sponge i would not use it if its a very wet wall)
Or you could use a tanking plaster something similar to this and plaster the wall, would always use a small dehumidifier in the room with damp problems and if you leave door open will help rest of house,you will be amazed how much water they remove
http://www.sovchem.co.uk/tanking/plasters-renders/25k-ready-render-rd.html

[shygirl]

many thanks for all the ideas, much appreciated.