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Tuesday, October 06, 2015


We had two different brand of ceramic tiles installed about a year and a half ago in a bar and restaurant. We have been having problems with the tiles losing their brilliance when an acid is spilled on the tiles. Tonic, lemon juice, and any other mild acid make the tiles become blotchy. What could cause this problem and how can we solve the problem? What could cause this problem and how can we solve the problem?


Our first thought is that ceramic tile is capable of holding up to anything short of direct blows with hard objects.
However, the Ceramic Tile Institute cautions about this view when acids are involved. You will find this material interesting.
There are a couple of possibilities.
First, the tile may have some sort of surface treatment applied, possibly in conjunction with the grout seal, and that is what the acid is reacting with.
Contact the installer and ask for particulars on the sealers they used, if any.
You can possibly solve the blotchy appearance problem by stripping off a finish if that is what is being affected, but do some research first to see of that is necessary. Stripping will certainly change the appearance if a finish has been applied for light reflection, the brilliance you mention.
Second, the tile, even if glazed, may be affected by even mild acids. The above document recommends a test and you may wish to try it. If it shows spotting, the tile is not acid resistant and probably should not have been used in this setting.
Does this mean the tiles’ integrity is being compromised and they will eventually disintegrate? Probably not, but your next step is to contact the manufacturers and consult with them. Perhaps they will recommend applying a seal to solve the problem.
Your basic defense against spotting is to simply flood the spill immediately with water and mop, wipe, or vacuum it up. This will dilute the acid and minimize any damage.

Lynn E. Krafft, ICAN/ATEX Editor