Do-It-Yourself Countertop Overlays

Calculate the number of tiles you will need. Measure the length of the counter surface you plan to cover with the overlay and multiply the length (in feet) by 2 1/2. This will give you the number of tiles you will need to cover a typical 24-inch deep counter (granite tiles are typically 12 by 12 inches). If you plan to cover a wider area, such as a kitchen island, allow for more tiles. Be sure to have extra tiles on hand in case of breakage or cutting errors.

Measure and cut tiles to fit irregular areas. Granite tiles can be cut easily with a diamond tile saw. Use rubber-padded clamps to secure the tiles when cutting them; regular metal clamps can cause the tiles to crack.

Move appliances out of the way. If you are resurfacing a counter next to a stove, refrigerator or other appliance, move that appliance out of the way before you begin your work.

Prepare countertop surfaces. Attach a 1/4-inch thick cement board to the countertop with either adhesive tape or screws. If you use screws, use a 3/8-inch or 5/8-inch masonry drill bit to screw each into place: this will ensure the screws lie flat against the board.

Apply mortar to the surface. Using a notched trowel, cover the cement board with a thick layer of thin-set mortar. Use dark-colored mortar if you are installing dark tiles and light-colored mortar is you are installing light tiles. Be careful to keep the surface of the mortar layer even as you work.

Lay down the tiles. Using a flat trowel, cover the back of each tile with a thin layer of the mortar and press it firmly onto the prepared surface. Install the tiles so that they fit snugly against each other. Granite tiles have beveled edges, so a thin, even seam will appear wherever two tiles are joined. Be careful to apply even pressure to each tile as you set it into the mortar; this will ensure that your new countertop will be perfectly flat. To ensure the tiles are installed correctly, lay a quarter on the tiled surface and run it along each seam with your finger: if it catches an edge of a tile at any point, this means the tile is not even with the others. As you install the tiles, also be mindful not to let them extend past the edges of the counter -- this could prevent appliances from fitting back into their original spaces.

Fill the seams between the tiles. Allow the mortar securing the tiles to dry. Mix unsanded grout with water to obtain a mixture with the thickness of peanut butter. (Do not use regular grout containing sand; this could scratch the tiles.) Rub the prepared grout into the seams with a grout float and use a moist sponge to wipe off excess grout. As you work, rinse the sponge frequently with clean water to ensure your surface stays clean as you wipe it.

Seal the seams. About a week after you have installed your new counter, seal the seams with two coats of polished granite sealant. This will protect the grout from stains and discoloration.