How to Work With Slate Flooring Tile That Is Not Square
- 1). Take the slate tiles to the area where they will be installed. Remove tiles from several boxes at once and examine them. Slate tiles can be installed with either side up; some sides are easier to work with than others and colors can vary from side to side.
Lay the tiles out in the space where they will be installed. Arrange them for color placement and cuts. Place the tiles that have the largest uneven sections or gaps on the edges, where they will be cut.
Open up the joints between the tiles until you are able to get a straight line between them. Placing them too close to one another will result in uneven grout lines, so open them up to as much as 1/4-inch. - 2). Mark the tiles that need to be cut with a straight edge and pencil. Cut these tiles on the tile saw and then check their fit with the other tiles.
Make note of any tiles that are thinner than the others, or that are thinner on one side. You will even this out with thin set, so you need to know where these voids are. - 3). Install the slate tiles in the pattern you've worked out by "backbuttering" them. Turn each tile over and use a trowel to place thin set directly onto the tile. Apply the thin set to each corner of the tile with more thin set being placed on thinner areas and less on thicker areas. The amount of thin set can vary from the size of a tangerine to the size of a grapefruit; when you press the tiles down, the thin set will even out slightly beneath the tile.
Additionally, spread a thin layer of thin set directly on the surface you're covering. Comb this layer with the trowel until you have ridges of uniform height.
Press the tiles into the thin set one by one, leaving the large grout joint and checking to make sure the tiles are level. If a tile needs additional thin set, pull it up and add more to the back. - 4). Allow the thin set to set for 24 hours before sealing the tiles with an impregnating sealer. Slate is porous and will absorb grout if the tiles are not sealed.
Use a foam paint brush to coat the tiles in sealer, and wipe away whatever is not absorbed with a lint-free cloth. - 5). Grout the tiles with a gray, sanded grout to fill the large grout joints. Pack the grout into these spaces with the float to ensure even coverage. Allow the grout 24 hours to cure.
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