Can new grout be layered on top of old grout?

Question

I had a shower updated by a professional contractor. He removed all the old tile and floor pan. There are several areas I'm concerned about.

There are gaps all across the tiles. There are spots where the grout is well below the edge of the tile. The grout is uneven and looks crumbling in places. The contractor says he'll come back and add another layer of grout. It's been 3 weeks since he grouted. Should I let him ADD grout? Of should he remove it all and start again?

He cut the wall tile and inserted the soap dish below the cut. He didn't finish the edges with silicone. Just some grout and there are big gaps between the grout and the soap dish. Looking at YouTube on soap dish installation, every one I saw shows a smaller hole the soap dish fixes to and then the soap dish hugs the tile - not set under it.

He put in a new pan and laid tile...kind of a mosaic style. There are spots that feel like I'm stepping on a bulge. He says that's normal because the pans aren't completely flat. What! I realize the new tile floor has to slope toward the drain. But shouldn't it be flat?

Answer 1

Yes new grout can be installed on old grout. Make sure the old grout is thoroughly cleaned and then wet before installation. I do this all the time. There is absolutely no need to start over and given the quality of the install you have had so far I would say that starting over might introduce more issues.

On the pan you can expect a slight slope towards the drain but the pan should be flat to the foot. Depending on what kind of pan he used your issues could be very severe or 1-2 hours of tile work.