Expert Answers in Stains

ANSWER - Efflorescence is generally a whitish stain caused by mineral precipitation.  Minerals within the concrete slab, the setting materials, and possibly the tile dissolve when subjected to moisture like salt in water.   The…

ANSWER - It is possible to grout over existing grout if there is enough depth to do so. 1/8 inch depth may or may not be adequate depending on the type of grout used. A…

ANSWER - Sanded cementitious grout has sand in it.  There is a chance that grout was not as hard as it should be and when it was cleaned it caused the grout to degrade to…

ANSWER - Depending on whether it is a glazed ceramic tile (has glass-like surface coating) or an unglazed (same material from top to bottom), you may have to approach it differently. I would expect that…

ANSWER - Generally speaking with some glazed ceramic tiles, which porcelain tile is a ceramic tile, or with some geological types of stone, they can etch when subjected to acid or some substance that is acidic.…

ANSWER - Normally a true polished granite is very resistant to abrasion.  So even if you used sanded grout, I don’t think it is likely that you scratch or abraded the granite surface.    There is…

ANSWER - I assume you have a natural stone hearth. Vinegar is an acid with a low pH. Some natural stones are more sensitive to acids than others. Acid sensitive stones can etch from being…

ANSWER - We have seen this type of problem before and we have investigated several situations similar to yours.   Generally speaking when the stone tile at the bottom rows of the shower wall darken…

ANSWER - Glazed tiles normally don't stain as they have a (glass like coating that is fired onto the surface of the clay body tile) surface that is impervious.  Unless when you say glazed you mean…