Fast Setting Thinset

Q: Probably the only "critical" part of our bath remodel is the tile around the toilet. How long will thin set take to set up enough to add grout, and then the grout to set up for the toilet? We only "need speed" for the toilet area. We do have access to another toilet, but it isn't convenient. The rest of the bathroom could be done at a bit more leisurely pace.

A: They make a fast setting mortar for this type of thing. You might be able to grout it in a couple of hours, and I don't see any reason that you couldn't set the bowl within an hour or two of grouting, if you really, really want to push it.

Standard mortar should set up overnight before grouting.

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Grout Between Porcelain Tiles‏

A. We had our bathroom done this spring in porcelain tiles with a brownish color grout in between the tiles. Recently my husband noticed that in a couple of places the grout is chipping and little bits of it are coming up. Should we have sealed it with something? The people who did this job for us didn't tell us to do anything to it. I wash it with vinegar and water and frankly, don't scrub it much at all. Should I be concerned about this flaking?

Q. You should be concerned about the flaking. Although sealing the grout will help keep it clean, stop it from turning color and free from mildew and mold it has nothing to do with flaking. Flaking is usually a result of one of three things:

The first is that the grout mixture was not mixed thoroughly and with enough water. The second is that the edges of the tiles were dirty when the grout was installed. Grout won't bind to dirt. The third is that the installer added grout on top of grout that had already begun to cure. Grout will not adhere properly to grout. If he did this, then it is the top layer that is probably flaking off.

Other than replacing the grout, which is a major exercise, I really don't have any suggestions for a fix. I would monitor the grout regularly, if pieces are chipping out, the holes should be immediately filled with a bathtub caulking to stop water from getting in behind the tiles. If it all starts to flake, then it will have to be replaced.

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