Tile has been used for thousands of years in homes to provide decorative surfaces as well hard, durable floors. Decorative tile is often used in on kitchen walls and countertops, while other types of tile are used in bathrooms, entryways and even large institutions such as stores and hospitals. When choosing tile, it is important to understand why some tile may only be used as wall tile, whereas other tile may be used as floor tile.
Before choosing the tile that you wish to install, it is best to give due consideration to how the tile will be used. While some tiles are designed to be shiny and beautiful, they may not be designed for the environment you intend to use them in. Similarly, even some tiles that are rated for use on a floor may not be durable enough to be used in the application you are purchasing them for.
The Porcelain Enamel Institute has developed a set of standards by which tile hardness is graded in North America. Many tile manufacturers use these standards to determine how a tile may be used. The standards provided by the Porcelain Enamel Institute provide a scale – called the PEI scale – of 0 to 5; this scale is used to determine the resistance of an enameled surface with respect to the wear that the surface can withstand before showing visible damage such as scratches. The durability scale ranges from 0 at the low end (which is unsuitable for floors) to 5 at the high end (which may be used in public buildings, shopping malls or other high-traffic areas).
Floor tile has a rating on the PEI scale that ranges between 1 and 5. Tile with a PEI rating of 1 is often used in areas with very low foot traffic, such as a master bathroom. Tile with a PEI rating of 2 may be used for the same applications as tile with a PEI rating of 1, as well as in areas with light traffic, such as bedrooms and main bathroom areas. Tile with a PEI rating of 3 may be used in these areas as well, and may also be used in all areas of a home except for entryways and kitchens. Tile with a PEI rating of 4 may be used for all of the previous applications, and may also be used in high-traffic areas such as an entryway or kitchen floor, or even as countertop tile. Tile with a PEI Rating of 5 may be used anywhere that tile is encountered, including commercial and institutional floors.
Many wall tiles are thin and have a high-gloss finish; therefore, wall tile that is often used for decorative purposes has a PEI rating of 0 or 1. Wall-specific tiles are unsuitable for use on floors because wall tiles are often porous and have a very soft glaze. The glaze on a wall-specific tile is prone to scratching, and the body of the tile is often too fragile to bear any weight. Interestingly, any tile that can be used on a floor may also be used as wall tile.