Hi All!
Old house built approx 1900 with solid external walls, currently some have plasterboard fitted to a thin 1” batten straight on the wall and some of it is dotted and dabbed to the wall.
I am thinking of building a 2x2 frame on top of the existing plasterboard, filling the gaps with 50mm celotex then a new plasterboard over the top.
Is this the best way to do it or should I remove the existing plasterboard first? Will the old plasterboard aid the insulation if I leave it there plus keep an air gap for the brick wall to breathe?
TIA, Adam