I am working on a shower which has recently been ‘gutted’ where the original tile, green board and shower pan has been removed. I had a plumber come in and replace the plumbing valve and the shower pan. The next step is to install concrete board. After reading several articles on the subject I have a few questions:
Water Proofing behind the substrate: I was going to install concrete board since green board is no longer recommended. When looking at the studs and insulation after removing the green board I did not see any water damage. The initial installation did not utilize any vapor barrier between the green board and the studs. The insulation between the studs contains a paper/foil (I think foil) on the side which faces the shower. This is almost like a vapor barrier in itself. My question is… should I install a vapor barrier between the cement board and the studs?
Water Proofing on the substrate: The general method of installing cement board is to use screws to attach it to the studs and then use thin set with fiberglass tape to secure the seams between each piece of cement board. I was going to use a membrane on the corners to assure a water tight enclosure. Is it recommended that I install the membrane over the thin set/tape in the corners or just use thin set and place the membrane over the thin set? Is a membrane needed if I use the thin set/tape combination? If I use a membrane on the surface of the cement board do I need to install a vapor barrier behind the cement board?
Thanks
Edited 6/29/2008 2:43 am ET by HandyMan2be
Replies
Please read 106402.4, above, where I answered a similar question.
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AaronR Construction
Vancouver, Canada