- 1). Prep your painted concrete floor by grinding with a concrete disk sander. Sanders can be rented by the day at an equipment rental retailer. Remove all paint from the surface of your floor. You will create a lot of dust with this process. Wear a dust mask. Tape off all vents and use a fan to blow dust out of a window if possible.
- 2). Use a vacuum or broom to remove all the dust from the floor.
- 3). Find the center of the room. Measure to the center points of two opposing walls. Use a chalk line to snap a line connecting the points, across the middle of the floor. Use a measuring tape to find the center of the chalk line and mark with a pencil.
- 4). Set your first row of tiles horizontally along the chalk line. Set a second row of tiles vertically from the center point of the chalk line. Spread a thin layer of adhesive on the back of each tile and press it firmly into place. Wipe off any excess adhesive that squeezes up between the tiles.
- 5). Continue setting whole tiles until you approach the walls. Use tile spacers if you are a novice at installing porcelain tile.
- 6). Use a tile cutter to cut the tiles for the outside edges of the room. Set these tiles in place leaving a space at the perimeter as wide as your grout lines.
- 7). Mix grout to the consistency of thick paste. Use a rubber grout float to spread the grout between your porcelain tiles. Remove excess grout from the tops of the tiles using a wet sponge. Allow grout to set for seven days before applying a grout sealer.
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