Our stone cottage is damp - we knew that before we moved in about a month ago. We've had some very good advice about reducing the causes - namely external ground levels, poor roof/gutters, lack of ventilation, bad rendering.
But in the dining room the previous owners have applied a hard plaster to the wall (a form of tanking I believe) and put down a concrete floor. The hard plaster goes just over a metre up the walls and is blown in a few places and damp has risen above it and affected the old plaster higher up the wall.
The floor was covered with a sheet of polythene, then some insulating sheeting and then a clip together wooden floor. The concrete under the polythene was very wet, which leads me to guess that there's no DPM installed.
The traditional answer is to hack off all the affected plaster and replace it with a Lime-based plaster and breathable paint (lime wash). Also to lift the concrete floor, and use flagstones on to a lime- mortar base, thus creating a breathable floor.
I've asked about chemical dpm's and though they'll happily sell me one, other people say this wont work with out stone/rubble walls.
But whilst I can lift the floor (I think), hacking the tanking plaster off the wall is nigh on impossible - I've been using a cold chisel and lump hammer but it's as if it's become one with the stone behind.
If the concrete floor has been laid with a DPM, then isn't it breathable already - couldn't I just mortar a thin stone floor over the top, without polythene and create the same breathable effect?
Is there a better way to get the tanking off the wall and replace with a lime-based plaster?
Simon