Install outdoor tile over concrete by first cleaning and repairing the concrete, followed by dry laying the tile, setting the tile in mortar and applying the grout. Application of a high-quality grout sealer once the grout cures can extend the life of the tile project.
To ensure a good bond between the concrete and the tile, clean the concrete using warm water and trisodium phosphate. This chemical quickly removes any dirt, grease or oil on the concrete. Before installing tile over sealed concrete, rent a scarifying machine to grind down the surface and improve the bond. Inspect the concrete for cracks and uneven areas, repairing these areas before beginning the tile installation.
Lay out the tile to determine where you need to make cuts. Position the tile so cuts are less noticeable, generally near the outer edges. Mix the mortar, and apply a thin layer to the concrete using the comb edge of the trowel. Insert spacers to position the tile evenly. Allow the tile to cure overnight.
Mix the grout following the manufacturer's instructions. Remove the spacers, and use a rubber float to pack the grout into the joints, pulling the float across the tiles in a diagonal motion. Wipe with a sponge to clean the grout. Apply the grout sealer two weeks later.