No offense toward your friend, but I'd seriously consider another contractor (recommendation at least). I am all for overengineering, but only when there's a benefit. If potential water damage is a concern, then your friend should be using a vapor barrier behind your cbu (cementitious backer unit, aka Durock, hardibacker, etc.), as recommended by most manufacturers.

I do believe it would be a huge mistake not to use reinforcing wire in your mortar bed. If you haven't already done so, please post your same question to the tilemen (and woman) at www.ceramic-tile.com. Good Luck. Greg

: Thanks for the response Greg,
: I did email USG and received the same response - only one layer is needed. I believe my friend recommends the two layers to add extra protection for any potential water damage. Looks like he is doing an extra precautionary step.

: I�ll have to keep researching the mesh/mortar issue.

: Thanks again,
: Heather

: : HI,
: : I'm doing a bathroom remodel and am currently focusing on building the shower. I plan to do a mortar bed for the floor and use durock for the walls. I have a friend who does this for a living and he has recommended two layers of 1/2" Durock for the walls - is this necessary or is one sufficient?

: : Also, for the mortar floor and floated curb, he indicates that he would never use any type of wire mesh for reinforcement. His arguement: the wire mesh could potentially damage the CPE pan. This goes against everything I've been reading in mortar bed construction. Can you please advise?

: : Thanks,
: : Heather