My house was built in the late twenties, mostly of recycled materials. Most of the walls and ceilings are what appears to be gypsum board with a thin plaster coating.I'm told that this type of board is made with horse hair which makes it difficult to work with. My current problem is that accoustic tiles glued to the ceiling in my living room are comming down bringing alot of the plaster coating with it.
Should I try to replaster the gypsum board and put up drywall? Or would it be better to remove the material up to the joists and put up plywood and drywall?