Joe,

 

In the past I have tested in place sealer by dampening an area with water.  The water may or may not soak in.  If it does then you probably have little or no protection left at all and you can start out with whatever sealer you desire.  If the water resists absorbing move it around the area a little to try and spread it out some.  You are doing this to prevent the next step from causing immediate penetration.  This next part you MUST do in an area out of normal sight.  Place a few drops of cooking oil on the area you are testing.  If the oil stands on top then you have a penetrating type sealer that is probably solvent based.  If the oil spreads but does not quite penetrate into the grout you probably have a silicone based sealer.  Be ready with a paper towel to blot up the oil if it starts to penetrate and if the oil does start to absorb quickly you have a water based sealer, which is the most likely scenario due to it being residential and, I suspect, near a big box store.  Also, being ceramic tile I highly doubt the installer used something other than a water based sealer. 

 

Another aspect to determine, and this may seem like splitting hairs but is important, is whether or not the sealer is ON the grout or IN the grout.  Big difference between topical sealers and impregnating sealers.   If it is topical it is alot easier to remove by stripping, as Dr. Fred has suggested.  If it is impregnated there is not much hope for removal, although these types of sealers sort of dissipate over time and can then be reapplied.  Hope this helps.

Monte Osterman
Technical Director - Fabrication

Stone and Tile Pros

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