The non-porcelain tiles are generally made from red or white clay mixtures. They are finished with a durable glaze which carries the color and pattern of the finished tile; although an assortment of tile dyes are used for coloring. They are used in both wall tile and floor tile applications and are softer and easier to cut than porcelain. These non-porcelain ceramic tiles are usually suitable for very light to moderate traffic as they are more prone to wear and chipping than porcelain tiles.
DURABILITY OF CERAMIC TILE:
(P.E.I. WEAR RATING SYSTEM)
To avoid choosing the wrong ceramic tile product, consult the following P.E.I. guide (used by most manufacturers) to rate the durability of each tile.
P.E.I. WEAR RATING
Group I Tile suitable only for residential / commercial walls. Not suitable and/or recommended for foot traffic
Group II Tile suited to general light residential traffic, except kitchens, entrance halls, and other areas subjected to continuous foot traffic.
Group III Tile suited for all residential and light commercial areas such as offices, reception areas and boutiques.
Group IV Tiles suited for residential, medium commercial and light institutional applications such as restaurants, hotels, hospital lobbies and corridors.
Group V Tiles suitable for heavy traffic both residential and heavy commercial applications such airports, malls and subways.
NOTE – the letters P.E.I. stand for Porcelain Enamel Institute.
The P.E.I. ratings are derived from a combination of tests that not only address the physical wear of the glaze surface itself, but also include a visual wear of the glaze surface appearance after the test. The wear ratings are normally listed on tile packaging labels & product literature.
Facts about the Clay Body:
The clay body, called bisque, is made up of various types of clay and other minerals. Combined, these raw materials give the bisque its strength and stability. Its density also determines the strength of the bisque as it relates to the water absorption level. The strongest bisques (those suited for heavy commercial installations) have the smallest and fewest number of air pockets which, in turn, will affect the over all water absorption, breaking strength, and impact resistance of the finished product. The density of the clay also determines if the tile is or is not suitable for outdoor use. Tile density is measured by the amount of water it absorbs.
Non -vitreous Tiles – absorb 7% or more of its body weight in water. They are suited for indoor use only and considered to be non-frost resistant.
Semi -vitreous Tiles – absorb between 3% to 7% of its body weight in water. They are suited for indoor use only and considered to be non-frost resistant.
Vitreous Tiles – absorb between 0.5% to 3% of its body weight in water. They are suited for both interior and exterior applications (covered and/or non-heated rooms not exposed to standing water) and considered to be frost resistant.
Impervious Tiles – are the strongest. They absorb between 0 and 0.5% of their weight in water.
Suited for both interior and exterior use and considered to be frost resistant. (NOT FREEZE PROOF). However, be aware of the C.O.F. (stands for coefficient of friction and means the slip resistance factor) when deciding on the use of these types of tile products in exterior applications.