Steam cleaning of grout very definitely does damage to tile grout. Steam cleaning of grout is done by steam cleaning machines utilizing high heat and high pressure. The steam does not damage tile or grout but may very well do damage to surroundings such as baseboards, paint and wallpaper.   Damage to grout is done by the extreme pressure applied to the grout joints by the steam cleaner. Here is an example:   In this photo you can see the pits and holes in the grout created by the high-pressure steam cleaning of the tile and grout. Yes, the grout is clean but it is now far more rough and […]