How to Install Ceramic Tile Over an Existing Countertop
- 1). Dull the surface of the countertop with a hand sander. Get it smooth and free of all grime and gloss.
- 2). Measure the length of the counter and find the middle. Mark a line at the middle, from the front to the back, using a carpenter's square to make the pencil line straight.
- 3). Use a notched mortar trowel to cover the countertop with mortar. If the countertop is more than 4 or 5 feet wide, then spread the mortar only along the front half of it; otherwise, cover the whole thing.
- 4). Set the first row of tiles into the mortar, starting at the center line and using bull-nose tiles. Arrange them so the finished edges of the tiles face forward, forming the front border of the counter. Build from the middle toward the edges of the counter, putting spaces between all of the tiles. Cut the tiles at the ends with your tile cutter.
- 5). Set the second row of tiles behind the first, using standard tiles and starting at the middle line. Build to the sides as before, cutting the end tiles as needed.
- 6). Repeat the process to cover the whole countertop, row by row. If you only covered half the countertop with mortar previously, cover the rest of it when you get to that part of the surface.
- 7). Let the tiles set overnight. Pull out the spacers. Spread grout over the whole surface with a grout trowel, pressing it into the lines between the tiles and smoothing it out. Wipe up the excess grout from the surface with a damp sponge. Let the grout set for two days before using the countertop.
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