installing tiled shower in my condo. One wall of the shower is the wall between my unit and the neighboring one. It was covered with 2 layers of 5/8 regular sheetrock. Fiberglass insulation fills the space between the studs with a paper backing on the outside. This insulation is for noise not heat. What is the correct way to layer the wall? Is it one layer 5/8 drywall, felt overlapping the shower pan membrane at the base then the 1/2 concrete backer board and then the tile? Or some other combination of layers? Thanks

I am in the middle of my first attempt at drywalling, and it is not going well. Mainly I didn't know what I was doing and the framing is not good. That makes drywalling especially hard. I have one particularly bad joint, where one side is pitched up at an angle. I wonder if I could take a random orbital sander to that and knock it down even. I can attach a vacuum to the sander, so it should be too awful. I also have a powered dust mask and a pretty decent air filter... Any compelling reason not to use a ROS. I know you are supposed to just use sandpaper on a block, but since my ROS has a vacuum attachment, can I use that to sand the mud just in general? I expect the fine dust probably isn't great for the sander, but I have several that getting pretty near retirement age, so if they get ruined it isn't a tragedy. Thanks.