Lenore, who is installing the granite slab shower? Start there and make your priority be hiring a VERY experienced tile professional - one you have vetted carefully to insure that their qualifications meet your design requirements and product selections. Stone slab installations are not for the B team, and especially in a wet area. Can it be done? Yes, depending upon the structure over which a solid surface stone is installed and the methods used. We install solid surface shower walls regularly, but from an empty cavity which we build to meet all specific design and installation specifications, including the pan. A solid stone slab cannot be supported by the pan (it is not meant to support a slab wall). A slab wall is pinned and tied so it is self supported, not supported by a pan. This is a very complex installation. A LOT to consider. As one example, the thickness of your slab? 2cm. 3cm? (effects the weight load on the space). And I could go on. After you have carefully vetted the qualified tile contractor, have this conversation with them. If you question or want to clarify their recommendations, check back or seek professional advice from other qualified sources. Please consult with a professional onsite. Good luck with your project.

Azek or other foamed PVC/wood flour products don't take on water like the wood will.

We are just in the process of using Caesarstone quartz for our tub surround and wainscot height behind toilet. There have been several threads on here recently about this topic. Most of the main quartz companies carry some in a 10 to 13mm (approximately 1/2 inch) thickness, which is what we got. They were supposed to do the templates today and didn't get here, or I would know more of how they feel of getting all the holes in one piece where the shower and taps are and 2 niches and a grab bar. I hope we don't get a rude surprise and they say they can't do it as the 2 slabs were brought in for us. Price was around $6,000 Canadian. I'm not positive, because we are also getting a piece of granite for the counter, and I have mis\-located my receipt in all the building stuff for the moment. Some companies like Cambria charged more for the thin stuff, saying it was special order. Caesarstone was $500 discount for a slab because it was thinner. I think Silestone also had thin slabs. Most of the slabs are about 10 ft. long by 5.5 ft. wide so work well size wise.

Thank you for your replies. If using cement board, what would be the proper way to construct the shower: Option 1 - ply vapor barrier, followed by cement board, followed by thinset and fiberglass tape on all seams and joints, followed by liquid waterproof membrane applied to all seams and joints only. Option 2 - cement board, followed by thinset and fiberglass tape on all seams and joints, followed by liquid waterproof membrane applied to the entire surface. Option 3 - some other method I may start to ramble here. I am leaning toward option 1 although option 2 appears to be the preferred method when constructing a tile shower. When using a solid surface, it appears that the purpose of the substrate is to provide a stable surface on which to caulk the solid surface. I have also read that the liquid waterproof membranes are meant for tile/thinset applications and not necessarily as a surface to caulk panels to. Not sure if that is true or not. On top of that, for a recessed shower caddy, manufacturer's instructions show to place a properly sized cutout in the substrate wall -- in other words whatever waterproofing methods used in option 2 go away at that point. With option 1, the ply barrier is still there. As an aside, I have also thought about using Densshield/Densguard as the backer although I don't know how well that material would hold up if there was a plumbing leak. I also run into the cutout-in-the-backerboard issue, similar to what I indicated above. Mabey I am overthinking this, but it is better to do it right the first time. Thanks!