Is anyone aware of successful long-lasting non-sanded grout over sanded grout? Based upon my inattentiveness(#@$&#!), I want to correct my mistake -- or did I stumble upon something that might work?
I have recently re-grouted portions of a ceramic tile tub/shower surround that I originally installed about 10 years ago and grouted with white sanded grout. Grout lines are 3/16" to 1/4" wide. The purpose of the re-grouting was 1) to grout an area where I reset a tile , 2) to repair areas that had cracked due to some minor settling, and 3) to repair areas that had been damaged by improperly used cleaners and/or stained. I removed the old grout in spots as needed. I took a chance -- color matching -- using a grout that appeared, in the container, to be whiter than the original as I was not sure what grout I had used originally. Mixed the grout with admixture rather than water.
The new grout turned out to be significantly whiter. Although the container said it was sanded, it was very fine, similar to non-sanded. One of the walls looks superb -- better than the original because of the whiteness and smoothness, with the new grout taking hold even in areas where I was not intending to fill. (I guess the old grout lines were recessed enough.)
There are areas on the other two walls where the grout lines are not as recessed and the new grout would not take hold. Thus I am left with two of three walls where the grout is rather spotty. New grout is covering from 1/2 to 2/3 of the two walls.
I have not yet sealed the grout.
Dilemma: I have very little of the new grout left over. I think I must have been given this grout by a friend, because I just realized that it was in a cylindrical package that said "sanded ... beige". I now suspect that the new grout is, in fact, non-sanded.
I would love to be able to simply dig out the top 1/16" of the old grout where the new grout did not take hold, buy any white non-sanded grout, and apply it to those two walls. However, if the non-sanded that I have applied is not going to hold up, then I might as well go back to square one!