Remove Grout from Ceramic Tile
Not a month goes by that someone doesn't email me and ask how to remove excess grout from a wall or floor tile job. People have sent me photos that make me cringe. In the photos one can see massive amounts of excess grout and a heavy grout film on the face of the tile. I have seen huge messes!
I think many people who work with ceramic tile for the first time are not aware of what grout really is. For the most part it is Portland cement. I can't imagine a person who doesn't respect how hard concrete or cement dries. What's more, it is sticky. You should see how tenaciously cement sticks to smooth metal shovels and trowels. The microscopic crystals that grow as cement hardens lock onto objects like Velcro®.
When people contact me about grout removal problems the common denominator is always, "...we were told the grout film would come right off." Well, a very light haze will come off of glazed tiles with an old bath towel, but heavier deposits can be a nightmare to remove.
Not all tile has the same ability to polish easily. Glazed tile that has a polished high gloss surface is indeed the easiest to work with. But quarry tile and some other tiles have a matte finish that makes them perfect targets for grouting nightmares. The rougher surfaces of these tiles are wonderful places for grout to attach itself. Slate is no different. The cleft surfaces of natural slate can be a huge challenge when it comes to grouting. The grout easily attaches itself to the staggered layers of silt that make up the slate rock.
The matte finish tiles, slate, and other delicate ceramic products need to be pre-treated before they are grouted. Years ago different tile manufacturers recommend things like oil soap and other temporary coating products. But a new industry sprouted as more and more matte finish tiles came to market.
You can visit a real ceramic tile store and buy an assortment of grout release agents. These are very cool liquid products that you wipe or brush onto tile after it has been installed. The coating temporarily seals the porous tile surface. You then grout and as you remove the grout and film, the grout release agent comes off at the same time. They do a superb job of making grouting jobs virtually trouble free.
Be sure to read the label and match the grout release agent to the material you are working with. Certain tiles and stone products require special grout release agents!
Clean Up Tools
To remove a grout haze from tile you need to be careful. You don't want to damage the tile surface. I have successfully done this using a generous amount of water that acts as a lubricant and synthetic fiber scouring pads. You can purchase some of these at local grocery stores. I have had good results from the Scotch Brite pads. These are the deep green pads that are about 1/4 inch thick.
The ceramic tile specialty stores often sell a similar pad called a Doodlebug. These cleaning pads are also superb.
Keep in mind that you must stop and check your progress from time to time. Rinse the slop water and use paper towels to dry the tile to see if you are making progress.
Think hard before using acid to remove grout mistakes. If you do, always get the tile slightly wet before applying the acid solution. Acid can also affect tile color!