Our house in SE Texas was built in 1960. I am about to remodel the standup shower (36"x36"), which will mean tearing out three ceramic tiled walls, two of which back up to an exterior brick veneered wall. I will be installing the new Hardibacker Hydro Defense cement board when I begin rebuilding the shower walls. The Hydro Defense is waterproof and does not require any type of waterproof membrane to be applied over the exposed surface.
When I recently tore out a ceramic tiled wall that is adjacent to the shower, which is also along an exterior wall, I discovered there was no insulation between the studs. I didn't think too much about it, but went ahead and installed new insulation anyway before putting up new greenboard. I have a feeling that when I tear out the shower walls, there will be no insulation there either.
So my question is this. Since we live in a warm climate year around do I really need to install insulation on the shower walls that face an exterior wall. Would it serve any purpose? Even though the Hardibacker is waterproof, I still plan to install a plastic vapor barrier maybe 3 feet up the wall studs just as a secondary defense.
Anyone have any thoughts on the need for insulation behind the shower walls, all things considered? Tks.