How to Install Ceramic Tile Over Cork Underlay
- 1). Find the center of the room by measuring and marking the center of each wall. Snap chalk lines between opposing walls by lifting the chalk line slightly and releasing it against the floor. The lines will intersect at the room's center.
- 2). Lay a row of tiles through the center of the room in both directions to find the optimum tile placement. Use the chalked lines to guide the tile rows. Try to arrange the tiles to use as many full tiles as possible. Mark the placement of test tiles using the chalk, and then remove the test tiles.
- 3). Mix a batch of thinset mortar in a bucket, using an electric drill with mixer bit attached, until it has the consistency of peanut butter. Apply the mortar to the center of the floor, covering an area of about four feet square. Use the flat of a notched trowel to spread the mortar, then turn the trowel on edge and use the notches to raise ridges in the mortar.
- 4). Place the tiles onto the mortar covering the cork underlay, using a twisting motion to set the tile in place for the greatest mortar coverage. Place tile spacers between the tiles for uniform spacing. Continue placing the tiles applying mortar as needed, until you reach the walls. Place the tile up to a point 1/4 inch from the walls, leaving the gap to allow room for the expansion of the surface with temperature changes. Check that the tiles are level, using a carpenter's level during installation. Level the tiles in place by tapping them with a rubber mallet.
- 5). Cut the tiles as needed to cover the edges of the room, using a tile cutter. Cut curves in tiles using a pair of tile nippers. Install the cut tiles to complete the initial installation. Leave the tiles overnight so that the mortar can set them into place.
- 6). Remove the tile spacers, and then grout the joints. Apply the grout by placing it onto the tiles and pushing it into the joints to fill them, using a grout float. Remove excess grout on the tiles using a damp sponge, and then allow the grout to dry for two hours.
- 7). Go over the surface of the tiles with a clean, lint-free cloth to remove tile haze. Wait an additional three weeks for the mortar and grout to cure completely.
- 8). Seal the tiles and grout to protect them from staining, by applying a layer of tile and grout sealant to the surface. Brush the sealant onto the grout and onto unglazed tiles. Glazed tiles do not require sealing.
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