The ceiling in my home office is,I believe plaster and lath. It's starting to crack, but I'm afraid to repair it as it could make things worse, because I don't exactly know what the paster is attached to or where. There seems to be some kind of visqueen behind the plaster, which is heavily textured. We have odd angles where the ceiling is pitched, and the past repairs/remodel were either done in haste or without experience. This is an old house, about 180 years that has been split up into apartments. If there is any way to repair this mess without causing more damage, please let me know!