How to Tile Over Tile Floor
- 1). Mix 1 cup TSP in a bucket with about a gallon of hot water. Scrub the tile floor with it. Rinse-mop with clean water. Let it dry completely.
- 2). Use a chalk snap line to divide the floor into four squares, with two intersecting lines across the middle of the floor in both directions, so they cross at the center. Readjust the lines if necessary to ensure they don't match the grout lines of the existing tile floor.
- 3). Use your notched mortar trowel to spread thin set mortar over the center of the floor, covering a few square feet over the intersection of the lines. The lines should still be visible through the combed pattern of the mortar.
- 4). Set the first tile in one corner of the intersection, pressing it firmly into the mortar.
- 5). Set more tiles around it, with tile spacers between them. Spread additional mortar and lay more tiles in a grid pattern, building out from the center toward the edges of the room, using the lines as guides.
- 6). Do the whole floor. Cut the tiles at the perimeter as needed on a tile cutter. Let them set overnight.
- 7). Remove the spacers. Grout the floor, using a grout float to press the grout into the spaces between the tiles. Wipe up the residual grout with a damp sponge. Let it set for two days.
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