Working with Irregularly Shaped Tile

Handmade paver tiles lend a pleasing informality to a room. Mexican tiles, saltillos, are one common choice; they have the added benefit of being very inexpensive. Handmade tiles will not be uniformly shaped; they can vary widely in shape, thickness, size, and color from tile to tile. Choose the tiles by inspecting each one and discarding those with severe blemishes.

Irregularly shaped tiles present several installation challenges. Not only are sizes unpredictable, but some of them may be significantly warped. Tiles of different thicknesses can create a tripping hazard if not installed with care. Because the backs are often not flat, back-butter each tile with adhesive. Handmade tiles cannot be cut easily with a snap cutter; a wet saw is much more effective. Some types require application of a sealer before grouting.

Floor layout for irregular pavers. When the tiles are not of predictably uniform size, layout becomes less precise. Rather than using plastic spacers, break the layout into a grid. For tiles that are approximately 12 inches square, use chalk lines to make 3-foot squares; each square will hold nine tiles. Dry-fit the tiles first, adjusting the spaces between them by sight. Then set the tiles one square at a time.

1. Set the tile. Comb on thin-set mortar. For tiles with irregular backs, apply adhesive on the backs as well to ensure an adequate bond. To make sure you can compensate for warped tiles and varying thicknesses, use a trowel with 1/2 inch notches to spread the adhesive.

2. Tap with a mallet. With uniform, machine-made pavers, you can use a beating block. With handmade pavers, however, tap on each tile individually. Use a soft mallet, not a hammer. You can set a rag on the paver to protect the surface further.

3. Clean the tiles. Remove mortar that oozes up between the tiles. Take care to keep mortar off the surface of the tiles. Before grouting, clean the tiles with a sponge and water. Apply sealer to unsealed tiles before grouting.

Working with Stone Tile

Stone tiles are made from stone that is quarried all over the world. Many types are available, and they vary widely in color and price. Polished stone has a shiny, almost glazelike finish that looks best on walls and interior floors. Honed stone has a smooth, matte finish that does not show wear as much as does polished stone. If properly sealed, honed tiles can be used in wet areas where polished stone would be too slippery. Flamed stone has a rough finish that is most useful on heavily traveled floors. Most stone is brittle, so the substrate must be strong— at a minimum, backerboard over 3/4-inch plywood. Because stone is heavy, be sure your floor joists are strong enough to hold it. Check with an engineer or architect if you are not sure. Cut stone tile with a wet saw, and use a blade suitable for the type of stone you are cutting.

Types of Stone






A limestone that has been changed deep beneath the earth's surface into a hard composition of crystals. Characterized by varied patterns and colors of veins.

Elegant appearance, used in many of the world's most famous buildings; beautiful and long-lasting.

Veins add to appeal, but weaken the marble. Dark-colored marble can fade in sunlight. Easily scratched and stained.


Quartz-based stone with a tough, glossy appearance. Colors range from light to dark, with varying patterns and graining.

Harder than marble; resists scratching. Easy to care for; resists acids. Excellent choice for kitchen countertops. Generally very dense and capable of withstanding freeze-thaw cycles.

Quarried all over the world, with varying characteristics from each region. Softer granites can sometimes show wear.


A rough-surfaced tile that is split, rather than sliced, from quarried stone. Available in slabs or as cut tiles, usually 1 2 inches square. Gauged slate is ground smooth on the bottom, while ungauged (or cleft) slate is rough on both sides.

Widely available and reasonably priced.

Somewhat brittle, with less range of colors than other stones. Dark slate may fade in sunlight. Irregular surface can produce undesirable flooring. Ungauged slate needs to be set in a thick mortar bed.

Materials to Use with Stone Tile - Be sure to get the right materials for setting, grouting, and sealing your stone tiles.

■ Latex-modified thin-set mortar works for most installations, but epoxy thin-set may be needed. Do not use organic mastics. Marble is somewhat transparent, so use white thin-set rather than gray.

■ With ceramic tile, a contrasting grout color is often used as part of the design. With stone tile, and especially with marble and granite, the objective is usually to minimize or eliminate the visual impact of the grout joints, so the surface resembles a solid whole. Choose a grout color that closely matches the stone. Use unsanded grout with marble and slate tiles, and epoxy adhesive as grout with closely spaced granite tiles.

■ Clear sealers can improve the appearance of stone tile and protect it from dirt, water, and stains. Use a low-sheen penetrating sealer on a floor; glossy sealers work well with other surfaces. Choose a sealer recommended for your type of stone. Test on a scrap tile to make sure it won’t discolor your tiles. Granite usually needs no sealer.

Shopping for Stone - Often the most attractive stones are the weakest because of their deep veins. Stone tiles are often sorted according to their background color, but variations within the sorted colors can be substantial. Look through each box of tiles before you buy. Get extras so you can return tiles that are unsatisfactory. Buy only from a knowledgeable and reputable dealer.

Setting Granite and Marble Tile

Granite and marble are usually quarried and then manufactured to uniform sizes and thicknesses. Standard tiles are 12 inches square and 3/8-inch thick with one side polished smooth. To minimize chipping, the exposed edges of granite and marble tiles are beveled. In fact, the edges are usually so smooth and straight that the grout joint between tiles can be very thin; sometimes the tiles are installed without any grout joints at all. Do a complete dry run before applying adhesive and laying tiles.

Tools: Wet saw or grinder with a diamond blade.

Cutting stone tiles. Use a wet saw. Natural stone sometimes breaks along existing fissure lines when you try to cut it. If this becomes a problem, cut the tile through only two-thirds of its thickness, then flip it over and finish the cut from the other side.

Set in silicone caulk. It may not look professional, but many tile setters use this technique. After you have done a complete dry run and know exactly where each tile will go. Lift up one or two tiles at a time and make squiggles of clear silicone caulk on the substrate. Set the tiles in it quickly but carefully.

Stone Cutter - The best tool for making neat rectangular cutouts is a small stone cutter equipped with a diamond blade. Rent or borrow one from the tile dealer or a rental store. (Tile setters often mount a diamond blade on an electric grinder.) After cutting in each direction, knock the cutout free and use tile nippers and a rubbing stone to clean up the corners.

Seal it first. Manufacturers recommend that some types of stone tiles be set with an expensive epoxy mortar. An alternative technique is to coat the back of the tiles with nonpourous epoxy. Once the coating has dried, the tiles can be set with regular thin-set mortar.

Finish the edge. You can buy special edging tiles for some types of stone. Or install narrow strips on the edge, and set the tiles on top of them, to produce the illusion of a massive slab. Have the exposed edges polished by the dealer, or polish them with a rubbing stone, and perhaps brush on several coats of clear lacquer.

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