Walls and Ceilings - Hardibacker vs. paperless sheetrock

I am getting ready to put my walls back on the wood studs and then it hit me: why not put hardibacker everywhere? I was planning on using hardibacker for the shower enclosure and then the paperless sheetrock throughout the rest of the bathroom, minus the ceiling which is still original. Would there be any problems with using hardibacker instead of drywall?

Does anyone know if one is a better heat barrier? Sound barrier?

How would you finish the wonder board?
I suppose it could be plastered over but I don't recall ever hearing of anyone doing so.

I've not seen or used any of the new paperless rock but IMO it is more gimmick than anything else. There are rarely ever any mold issues with regular drywall providing it is kept painted and there are no moisture issues.

Insulation in the wall cavity would be your best sound reducer.

Yes, you could do it, but why?? Hardiboard comes in 3 X 5 sheets - drywall in 4X8 or 12 - it's easy to work with and already has a smooth finish. It's cheaper than any hardiboard/wonderboard/etc. and easier to install.... Haven't checked out "paperless drywall" - so can't comment on it's net worth.

Great replies from all. I was thinking I could paint the hardibacker just like drywall, but as suggested, the difficulty in handling and the extra seams makes it too difficult to use instead of drywall. Thanks again!

It is not a gimmick. It comes down to what you can not see can hurt you. If the back of the traditional sheetrock gets wet it can be a breeding ground for mold. Very dangerous.
The building industry is sadly out of step with regard to health issues for inside a house.

IMO the dangers of toxic mold are greatly overstated. It ranks right up there with the dangers of CCA PT. Toxic mold is fairly rare. The vast majority of household mold spores are not dangerous to humans.

With that said, I can't agree with assigning unwarranted blame to a product or an entire industry. Paper faced drywall is used safely in literally millions of homes. All without mold problems. It is inexpensive, easy to install, and durable. It's a homeowner's responsibility to properly maintain their home including replacing wetted drywall and properly ventilating humid spaces.

I've used paperless drywall on two bathroom remodels and I'm sold on it for a DIYer. In addition to the peace of mind that there is no paper to rot, it finishes much easier (to me) than regular papered drywall. It takes paint great and best of all you almost can't sand it to a fuzz. I'm sure that makes no difference to you pros, but to us guys who finish drywall maybe once a year, that's big plus.

I could be a saleman for this stuff.