ADA shower stall - seeking input before tilers return tomorrow
This is a follow-up to the below thread:
Background: for ADA reasons, our shower stall was built with no curb. There is a continuous waterproof membrane and continuous mudbed over it that run from the shower to the rest of the bathroom. Water had been penetrating from the shower stall to the adjacent marble flooring, noticeable as the marble darkened. We guessed that the problem was water moving through the mudbed to outside the shower. Can't say for sure. Back in January, the tile contractors dug out the tile and mudbed on the nonshower-side of the saddle and applied a black waterproofing mastic to the vertical surface of the mud directly underneath the saddle, connecting it with the adjacent waterproof membrane. They did not apply mastic to the leftmost few inches (where we didn't notice water penetration until after mongoct pointed it out - thanks again!!) and not sure how well it was applied everywhere else. I figured that if this was in concept the right fix, we would see no further (or less) water penetration on the right end of the saddle (where a lot of mastic was applied) while the left side would be the same as before.
The update is that after showering for a couple weeks, we noticed the marble floor outside the shower darkening again! On both sides. It's hard to say whether it is penetrating as fast as or slower than before, but it seems about the same to me. IOW the mastic didn't seem to do anything. Long story short, the sponsor got involved this time and the contractors appear motivated to fix it properly (w/o incurring too much expense) this time. Their proposal now is to remove the saddle, all the mud underneath and apply the waterproof mastic on the vertical surface of the mudbed surrounding ALL sides of the saddle. I really hope this works, but am skeptical based on our experience so far.
I've taken several pictures of what the space looks like right now to see if anyone has insights or tips based on what they see. So far the tile contractors have removed the saddle and mudbed underneath. They are waiting for the area to dry before they apply the mastic. I believe they are going to do a water test (where they fill the shower stall w/ water) once the area has been remudded & saddle installed.
One question, too - it looks like they put up greenboard in the shower stall. Would the waterproof membrane under the mudbed in the shower continue past the greenboard and vertically, up the other side of the greenboard?
Sorry if my post is rambling and long! I am writing this quickly in hopes of getting some feedback before the contractors return tomorrow morning.
Many thanks in advance!
right side of shower:
right side of shower, facing rest of bathroom:
left side of shower:
left side of shower (left side of photo is non-shower side):