1

I have a bathroom, already sheetrocked with the green moisture resistant sheetrock.

My tile guy told me I need to do hardiback for him to tile on, for the shower/bath's tiling on the wall.

Rather than ripping out the green sheetrock and redoing it in hardiback, my plan is to staple up a vapor barrier (just a 3-mil plastic dropcloth), and then screw 1/4" hardiback board over the top of the green sheetrock.

Can I reasonably do 1/4" hardiback over a vapor barrier over green sheetrock, for a tiled shower/bath?

Improve this question
5
  • You can do whatever you like. Your tile guy might not like your choice, though. 5 years down the line, you might not either. But if you are doing it to suit your tile guy, ask them. I know I'd kick anyone suggesting use of a 3 mil dropcloth as a vapor or moisture barrier offsite then and there. That's amateurish in the worst way.
    – Ecnerwal
    Commented Aug 9, 2023 at 1:22
  • Green board can be tiled, but if you want it to last better use the fibre-cement. There no point half-arseing the fibre cement, you may as well stay with the green board, but it seems that to do that you will need a different tiler.
    – Jasen
    Commented Aug 9, 2023 at 10:39
  • @ecnerwal I am an amateur. =P What should I do instead of plastic dropcloth, under the concrete board?
    – Jamin Grey
    Commented Aug 9, 2023 at 17:34
  • @jasen My tiler will do whatever, hardieback was his strong suggestion. My question is, what should I do to make my bathroom last well long-term? Rip out the green sheetrock? Why should I not just do thin concrete board over the green? (the extra thickness will be easily hidden) And what would I put between the green and concrete-board? I want to do what's best here long-term, not what's easiest, short-term.
    – Jamin Grey
    Commented Aug 9, 2023 at 17:37
  • @jasen Basically, I'm asking how to not half-arse it, because left on my own, that's what I'd accidentally do. =P
    – Jamin Grey
    Commented Aug 9, 2023 at 18:05

1 Answer 1

Reset to default
4

Glue and screw the cement board to the green-board.

Use 1 1/2" screws to anchor the panels to the studs.

Forget about the plastic. Seal the walls and the floor with a waterproofing and uncoupling membrane such as AquaDefense or Red Guard

If your tile guy doesn't like that, you need a new tile guy.

Improve this answer
4
  • Am I sealing under the hardiebacker, or am I sealing over the hardiebacker? The floor is concrete, do I still seal the floor?
    – Jamin Grey
    Commented Aug 9, 2023 at 17:46
  • you apply the water sealer to the hardiebacker, then tile over that. Water sealer should be applied to the floor of the shower, if you do not have a PVC liner.
    – RMDman
    Commented Aug 9, 2023 at 17:57
  • The shower is also a bathtub, so the "floor" of the shower is the bathtub (the floor of the entire bathroom is concrete, on the ground floor of the house, but raised above outdoor ground level) Do I still seal the concrete floor under the bathtub?
    – Jamin Grey
    Commented Aug 9, 2023 at 18:04
  • 2
    No, it is not necessary to seal the floor under the tub. The order would be: hardi over green board, sealer over hardi, tile over the sealer.
    – RMDman
    Commented Aug 9, 2023 at 18:13

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.