You can’t fix that without a complete tearout and redo. It compromises the waterproofing behind the tile. What system of waterproofing did the contractor use? Do you have in progress pictures of this being constructed?

julia3142:

I was just called back to fix an allegedly leaking shower door I installed. There was nothing wrong with my installation, the water was dumping onto the floor because the top of the curb was pitched away from the shower as is yours.

I'd need some pictures to verify, but you may be able to fix this with a one-piece solid surface curb cap pitched properly. This will have to be coordinated with the shower door man. Have the niches capped to pitch too. I know you're anxious to finish, but you've got to be patient and get this right.

thanks for the input, Sophie and Joseph. The contractor ended up taking off the top tiles from the curb and installing a single piece of quartz. But when he took off the top, I noticed that the only thing underneath was pressure treated wood, either with thinset on top of the wood, or redguard and thinset, I couldn't tell.

"But when he took off the top, I noticed that the only thing underneath was pressure treated wood, either with thinset on top of the wood, or redguard and thinset, I couldn't tell."

Thhat's not good and doesn't bode well for the waterproofing on the balance of his work. That is in no way shape or form waterproof. Period. Stop.