HI, i have a 400 year old cottage which has the old lime and hair plaster. The plaster at the tops of the wall seems to have softened and is falling away and is loose in places. Also on one wall upstairs where the chimney breast pretrudes from the wall a crack has appeared. My idea is to remove the loose and soft and use a lime undercoat and then top coat....if that is the right thing to do? So far the only product i have come across (and in my local area of Halifax) is Limelite. Really needing some advice on how to approach this situation. The walls are stone with no insulation. Many thanks.