Hardibacker over drywall - Contractor Talk - Professional Construction and Remodeling Forum

highpeaks · 09-25-2009, 10:45 PM

For years I've installed 1/2 hardi over 30lb felt stapled to studs. Last week I spoke to another contractor who uses 1/2 drywall over the studs. Then laminates felt with roofing adhesive to the drywall. Then the hardibacker.

He says that is makes for a stiffer wall behind the tile. Does anyone use this technique? Any comments? What type and size screw would I use to make up the additional 1/2"?

**ChrWright** · 09-25-2009, 10:56 PM

That sounds like wasted overkill and an invitation for mold issues.

Is this in a shower? God I hope not. Gypsum has no business anywhere near a wet location.

naptown CR · 09-25-2009, 11:38 PM

I have seen this done on too many occasions to remember. I think the original intent was to make it look like a mud set wall. Mud caps fit perfectly over the radius of durock. Tore out a bunch and didn't run into any more mold etc than normally seen behind shower walls. The felt might help but redguard over the durock would be better.

angus242 · 09-26-2009, 08:46 AM

No need to double post:

http://www.contractortalk.com/f73/ha...-shower-65482/