Should I install a vapor barrier behind cement board in a shower?
lindselove
| Posted in Interior Design on
I live in a cold climate.
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Here's the answer from my Fine Homebuilding article, Tile Backerboard Options:
"Manufacturers of cement backerboard generally recommend that a moisture barrier of some sort (WonderBoard calls for #15 felt or 4-mil polyethylene sheeting) be installed behind the backerboard when used in a wet location. According to some tile contractors, however, this is bad advice. “Plastic is a bad idea because you are nailing it on and putting holes in it,” says Tom Meehan. “When there is plastic, I’ve found mold behind the plastic. It locks any moisture behind it, and the moisture can’t dry.” If you want to waterproof the wall, Meehan recommends the use of a liquid-applied membrane such as
Laticrete Hydro Ban or Mapei Mapelastic AquaDefense on top of the backerboard. For a steam shower, he prefers a sheet membrane from Kerdi or Noble."