Looking Advice
Working on a new shower where there was once a whirlpool tub that never got used. Decided on using this space since I did not have to move the plumbing wall or the drain line. I am using Permabase Plus as my backer board. In order to free up space in the bathroom I have installed a pocket door that is on the back wall of my shower.
My issue is for the last two inches of backer board at the top of the shower base there is nothing to screw into and the backer board has some flex in that spot. There was not room to put a nailer behind the bench. The bench will have a granite/quartz top and my solutions have run the gamut from screwing the last two inches into the granite from the back once the granite is installed or simply siliconing the backer board to the granite once it is installed. Another question is will the tape and thinnest firm that flex up enough to trust it over time.
I have included pictures below to show my dilemma and all suggestions would be appreciated.
I think you will be fine, 2" is pretty good. Yes, use the alkalai resistant mesh tape and thinset it should be fine.