Like any other home repair project, you need to be knowledgeable about sealing your tile floor. Some tiles are more porous than others, therefore requiring a different type of sealant. Once you know what you will need to seal the tiles properly, you then can follow a few simple directions to achieve the desired look and protection of your renewed tile floor.
Test one of the floor tiles with a few drops of water. If the spot on the tile turns dark, that means it absorbed the water, and you will want to use a petroleum-based sealant. If there was no absorbency, you can use either type of sealant.
Wash down the tile floor with hot water and a rag. The point of this is to try and remove any dirt and grime from the tiles and grout before you seal them.
Allow the floor to dry for 24 hours to make sure the tiles and grout will not absorb the sealant if capable. Also, you do not want any moisture build-up in the tiles since that will counteract the sealant when trying to fill the porous holes.
Dip your rag into the sealant container and begin gently swiping the rag across the tiles. Be sure to do this in one direction, either left to right, or up and down, so that there is no chance of adding any sort of altered appearance to the tiles.
Wipe off any excess sealant around the edges of the tiles and grout. Make sure you allow the sealant to stand and dry for 24 hours before being cleaned or walked on.
The more sealant you apply, the better the chance of the pores and holes in each tile to become filled and less porous. This does add additional drying time, however.