We have a small bathroom in our master bathroom in which the ceiling is peeling. I painted it many years ago when we first moved in but the bathroom at the time did not have an exhaust fan. I tried sanding it but the ceiling is textured and it seems impossible at this point. Would it be easier to just apply another piece of sheetrock over the existing? If so should I use green board or regular sheet rock? Also, what thinkness should I use? Any advice would be appreciated.