Sorry I think you misunderstood, its a shower panel not a shower enclosure. A shower panel is a panel that has a shower head and body sprays on one panel. To install it they will have to drill through subway tile glass to screw in the mounting brackets and my tile guy doesn't know how they will drill through the glass subway tile he installed without cracking it. That is why I was wondering if anyone had experience with this without cracking the tile and the best method to be used.

hello Jillianfl. Top photo is the one I used to remodle my last bathroom. I loved it and got lots of compliments on it. I'm now renovating a new home, and I have the same concerns about the shower flooring. Did you end up getting some advice? What did you end up going with? Thanks in advance!

The home depot associate (tile specialist) suggested 1/16 spacers but use a flexible mortar to allow expansion/contraction. (I may not have said that correctly.) I will get advice on specific thinset and grout from my contact at the tile shop (who was a tile contractor). Thanks everyone!

Bspoke is correct. In addition look at the backside of the fallen tile. Most likely it is clean. Showing little sign if any of adhesive transfer. Do point out the required 95% coverage in wet areas. I personally would use my fist and bang the walls hard and every where while the installer is there. That tile falling is not a god sign. I often see this when folks use cement board and don't sponge it first. (give it a drink) as required. The board will suck the moisture from the setting mortars resulting in your scenario. Use a screwdriver and tap around. You will hear the difference when tile is hollow (not bonded). Which brings us to the question of waterproofing. In progress photos are the only way to help you with that topic. Not sure why soaking tile was suggested above as we have no idea what the tile is being installed. I very highly doubt the body is that soft / porous to require soaking.