I've completely gutted an old bathroom down to the studs. Read a lot, and can't find consensus on this: What goes on the walls? I know to use cement backer board, but do I also need a waterproof membrane either behind or on top of the backboard before tiling? This will be the main shower in the house - so frequent use.
One article I read says that cement backer board, although not damaged by water, is NOT impervious to water, meaning water can go through it to other stuff behind it (like wall studs or whatever). Is that true?
If a membrane is recommended so, what type of membrane, where can I get it, and does it go behind the cement board, or over it?
Related question: what goes on the floors? Planning on using cement backer here to over plywood subfloor. DO I also need a membrane on the floor? Same questions as above.