I just bought an apartment in a pre-war building in New York City. The walls are not plaster over lathe and not drywall. They have a wallpaper-like material over plaster or concrete (I have to do some more research). Is anyone familiar with this wall covering? It is now peeling and a real mess, so I need to remove it and skim coat the walls with plaster. Any tips/suggestions for how to go about this?