I want to put ceramic tiles in high traffic areas - but I have 24" centers and have been told the grout will constantly be a problem because of too much movement. Is there such a thing as a flexible grout that will withstand this?
I have seen grout that has a flex agent in it in the past. If the floor has to much movement you probably will be cracking tiles as well. Maybe look into stiffening the floor structure or possibly a floating laminate that has the look like ceramic.