We had our home built in 2021, we were told to pick out the tile we wanted for the shower floor from Lowe’s/Home Depot, chose a white/grayish stone tile and wanted black grout as our whole bathroom was white/black themed. We got a message from the foreman when they went to tile the shower floor that the black grout “stained” the white tile and turned them all gray and we didn’t like the look of it. So they said they could do white over top of the black to help lighten it up again. We told them if they’re able to do that then yes. This is our first house and we don’t know much when it comes to tile and grouting so we relied on the professionals doing their job correctly.
Fast forward to now, there are cracks in the grout, the white grout has come off in some spots so you can now see the black grout. The grout has also cracked where the floor meets the wall.(Side Note: we got a quote from a glass company for adding a shower door and the tech noticed the crack where the floor meets the wall and told me to put some clear waterproof caulk around the whole thing so I did.) We don’t know if they sealed it afterwards either. My biggest worry is water damage where the grout has cracked. All I’m aware of them putting on the floor and the walls before it was tiled is what I believe is AquaDefense.
Am I able to grind away the some of the black grout that has come through to re-grout that area with white again? Same thing for the cracked areas? And should it be grouted where the floor meets the wall or should caulk be used?