QUESTIONCleaning Old Tile - im intersted in cleaning quarry tile that are 50 yrs. they are unglazed. they need to be clean up and reseal to bring out there natural color.. these tile were made in england some time after the war .. so would be quite intersted in some ideas or tips that u might have. thank you for your time
ANSWERANSWER - To determine how to clean an unglazed (through body) tile you first need to determine what substances are causing it to be dirty.
If there is a cement residue then a diluted phosphoric or Sulphamic acid can be used. Acid will not remove grease or some other organic stains.
I would first use a degreaser or a detergent. Wash the pavers down well and while wet apply the cleaner and let set for 5 minutes. Then scrub with a brush on an extended handle. Then either wash off with clean water into a drain or use a wet and dry vacuum to pick up the dirty water. Next rinse with clean water again. Let the pavers dry thoroughly and apply a penetrating sealer if you want a natural look or use an enhancer sealer if you want more of a wet look. Be sure to wipe the excess sealer off with a lint free cloth after about 5 minutes.
I recommend you use products recommended by a manufacturer of cleaners and sealers for ceramic tile. We do have a list of Cleaners and Sealers manufacturers under our Resources in Expert Answers.