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Sometimes you need just a single tile to replace a missing piece around your fireplace. Other times, you need an entire suite of complementary floor and wall tile to create a period bathroom, hall, or kitchen. Whatever your tile problem, here's the path towards a solution.

Although we spend our lives surrounded by ceramic tile, few of us are familiar with the physical chemistry that creates and defines the wide variety of fired clay products grouped under the broad generic name "tile."

DUPLICATING HISTORIC TILE:
One of the simplest -- though not inexpensive -- tasks is duplicating missing historic tile. Every once in a while, you may get lucky and find the tile you're looking for in an architectural salvage emporium. More likely, however, you'll have to get the tile(s) duplicated as a custom project. Obviously, this will be a time-consuming and fairly expensive undertaking. However, there are quite a few craftspeople and heritage tile studios who can execute this kind of work. The accompanying list of Ceramic Tile Suppliers contains the names of several studios that are skilled in historic tile restoration and replication.

But if you're not working with a tile studio on a custom replication, you've got tens of thousands of tile patterns and types available from manufacturers and distributors. Here are some guidelines for picking your way through the confusing world of tile:

WATER ABSORPTION:
Most people distinguish tile visually by color, texture, and pattern. But tiles can also be identified by many other physical characteristics. One of the most important of these factors is water absorption. For example, a tile that absorbs significant amounts of water is not suitable for outdoor use in freeze/thaw zones. Tiles can be divided into 4 major groups based on their tendency to absorb water:

Vitreous:Tile that will absorb more than 0.5% of water by weight, but less than 3.0%.

Semi-Vitreous:Tile that will absorb more than 3.0% of water by weight, but less than 7.0%.

These water-absorption characteristics have a major effect on the suitability of tile for different applications.

GLAZED WALL TILE:
Because indoor wall tile is not subjected to hard use, wall tile is generally made from light-duty clay bodies with a water-impervious glaze. Sometimes called "white tile," glazed wall tiles are manufactured by the pressed-dust process, resulting in a smooth, uniform product. Glazed wall tiles are relatively inexpensive, easy to clean, and normally come with spacer lugs that make for easy installation.

CERAMIC MOSAIC TILE:
Unlike pictorial mosaics that are composed of thousands of tiny irregular tesserae, ceramic mosaics use small regular tiles to make geometric patterns of varying complexity. Some tile studios provide individual tiles that you assemble on site to create custom geometric designs. At the lower end, geometric mosaics can also be factory-mounted on a sheet backing in one- or two-foot squares so they can be installed quickly. Ceramic mosaics come glazed and unglazed, and in a variety of shapes including squares, rectangles, and hexagons. Unglazed ceramic mosaics are often used in flooring applications.

QUARRY TILE:
Quarry tile refers to tile produced by an extrusion method; clay or shale dough is forced through a die in a continuous ribbon, then cut into tiles and fired. Paradoxically, this mechanical extrusion process can give quarry tile a "natural" look. Quarry tile is normally left unglazed, but occasionally glazes are used.

The extrusion process produces a dense skin on quarry tile that is quite resistant to water absorption. Unglazed quarry tile provides an economical, stain- and slip-resistant floor. In commercial applications where additional slip-resistance might be needed, some quarry tile is given surface with tiny abrasive particles added. Some quarry tile are sufficiently water-resistant to be used outside in freeze-thaw zones; other quarry tiles are not. So be sure to consult manufacturers' application data before using quarry tiles for exterior paving.

PAVER TILE:
Paver tiles are often confused with quarry tiles because they are similar in size and weight -- and both are used primarily in flooring applications. Produced by the pressed-dust method, paver tiles differ from quarry tiles because of the larger range of colors and finishes available. Paver tile can come glazed or unglazed, and have very low water absorption -- usually in the "vitreous" or "impervious" range.

Like unglazed ceramic mosaics, paver tiles find wide use in flooring applications. The two tile types share similar physical characteristics; the major difference is that paver tile come in larger sizes and a greater variety of textures.

TERRA COTTA TILE:
Terra cotta tiles have a rustic charm that derives from being made of natural clays, and which is accentuated by variations in tones, textures, and size. The variations and imperfections are considered a desirable feature of terra cotta tile. Terra cotta tiles are usually highly water absorbent, which makes them unsuitable for most outdoor applications. When used indoors, terra cotta tiles are often given a sealer coat to improve their stain resistance. Terra cotta tiles are often used in flooring applications because of their size and thick body.

SALTILLO TILES:
Mexican terra cotta floor tiles -- often called "Saltillo" tiles -- are produced in Mexico using traditional handcraft methods. The tiles are fired at low temperatures and are especially water absorbent. Testifying to their rustic origins, sometimes a Saltillo tile will bear the imprint of a dog paw, chicken claw, or some other animal that might have strayed across the tile's surface as it lay drying in the sun. Saltillo tiles tend to be irregular and as such are not suitable for thin-set installation methods when being used for floors. Traditionally, Saltillo floor tiles are set in a mortar bed.

TEXTURES:
Ceramic tiles can have two types of textures: Visual and tactile. Tactile textures are physically present on the surface, such as ribbed and embossed tile. Handmade tiles often have slight irregularities in the surface that, when taken together in a group, create a subtle texture. Visual textures can also be created with glazes, where variations in light and dark tones, or flecks of color in the glaze, can create the visual impression of textures. In general, textured tiles tend to create a less formal, more rustic look suitable for such styles as Arts & Crafts, Southwest, and Spanish Mission.

Honed and matte tiles have a uniform slightly roughened surface that imparts a subtle texture. Honed tiles are unglazed tile that are ground to a smooth dull surface during manufacture. Matte finish tiles have glaze that creates a dull, low-luster surface. The slight roughness of honed and matte tiles make them slip-resistant and thus more suitable than glossy tile for floor installations.

GLOSSY SMOOTH TILES:
In contrast to textured tiles, smooth glossy tile create a more finished, formal look. Also, smooth glossy tiles resist dirt and stains and are easy to clean. As a result, smooth glossy tiles work well in high-maintenance areas that require frequent cleaning, such as kitchens, bathrooms, and entry halls. But they are slippery, and should not be used for floors.

ENCAUSTIC TILES:
Encaustic tiles are a patterned tile that combines two different clays within a single tile. Because the pattern is created by a 1/8-in. thick colored clay slip that contrasts with the tile's main clay body, the pattern in encaustic tiles is extremely durable in high-traffic areas. Consequently, encaustic tiles very popular in the late Victorian era for floors in both homes and public buildings. With the popularity of the Victorian Revival today, specifiers can get true encaustic tiles -- made just like they were in the 1880s -- or more-economical "faux" encaustics, where the pattern is silk-screened onto the glaze and then fired. The "faux" encaustics are quite adequate for residential installations, but for public buildings you're better off with the real thing.

CERAMIC MURALS:
Ceramic tile murals are made by combining a number of smaller tiles together to create a larger scene or picture. Some murals use a relatively small number of large tiles -- each with a significant portion of the picture silk-screened or hand-painted on it. Other murals use the standard 4x4 tile as the basic pictorial unit. In either case, and no matter if it's a stock or custom design, the tiles have to be site-assembled in the proper order.

SLIP RESISTANCE:
In our litigious society, slip resistance in floor and paving tile is of increasing importance. Water on a tile surface is the most common cause of slips and falls. In kitchens, the possible combination of grease with water can create super-slippery conditions. Slip resistance is imparted by roughness in the tile surface.

There's an ASTM test (C-1028) to rate the slip-resistance of ceramic tile -- but the test has not been adopted by all tile producers. So there is no universally accepted method for rating relative tile slip-resistance across various manufacturers lines. The Americans with Disabilities Act (ADA) does set out guidelines for static coefficient of friction (SCOF) for floor surfaces:

To complicate matters, OSHA recommends a minimum of 0.5 SCOF for a safe slip-resistant floor. Many tile manufacturers provide flooring tiles that meet the above recommendations -- but you may have to dig a bit to find comparative SCOF data. It certainly pays to do this research on large installations, because the cost of remedying an original specification error -- once the tile have been installed -- can be enormous.

MAINTENANCE:
Even the best floor tile specification can go awry if proper maintenance procedures are not followed and grease and other slippery materials are allowed to accumulate. Note: The more slip-resistant the tile, the harder it may be to clean. That's because slip-resistance comes from roughness in the surface -- and roughness also traps dirt and grime. Thus the ideal floor tile spec is one that provides just enough roughness so that it provides a safe walking surface -- but not so much roughness that it becomes a maintenance headache.

TEST FOR STAIN RESISTANCE:
Before installing an unglazed tile, you might want to test it for stain resistance. An easy test is to take a few sample tiles and drop butter, ketchup, and other greasy foods on the surface. After six hours, wash the tiles and see how much staining has occurred. If staining level is troublesome, consider a penetrating sealer. Penetrating sealers are absorbed into the pores of the tile and make them more stain-resistant and easier to clean. Sealers make the most dramatic improvements in the more porous types of tile -- the non-vitreous and semi-vitreous.

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