A mixture of clays that are pressed into shape and fired at high temperatures which gives the tile it’s hardness. The bisque, or body, of ceramic tile may then be glazed, or left unglazed depending on it’s intended use.
Classifications of Ceramic Tile
P.E.I Wear Ratings from the Porcelain Enamel Institute
• Group I: Tiles that are suitable for residential bathrooms with light foot traffic. Generally wall tile products fall into this group. Some wall tiles can be used on the floor. Consult the manufacturer of the tile for their recommended areas of application.
• Group II: Tiles that can be used in residential traffic areas, expect areas with high traffic, such as in kitchens, foyers, laundry rooms, etc.
• Group III: Products that are recommended for all residential installations.
• Group IV: Tiles that are suited for all residential and light to medium commercial.
• Group V: These tiles can be in heavy traffic areas and are recommended for wet areas where safety is a concern, such as in food service areas, exterior areas, shopping malls and swimming pools just to name a few.
Glazed – The most common style today in floor and wall tiles, as well
as for residential and commercial applications. A liquid glass is
applied to the body of the tile and fired at high temperatures. The
glazing becomes hard and non-porous resulting in a flooring that is:
• Stain Resistant
• Scratch Resistant
• Fire Resistant
• Doesn’t Fade from Sun Light
• Slip Resistant
• Easy to Clean
Shiny glazes are softer, can be scratched easier, and can be slippery than the satin or rustic finishes.
Unglazed – There is no glazing or any other coating applied to the tile. Their color is the same on the face of the tile as it is on the back resulting in very durable tiles that do not show the effects of heavy traffic. The most common unglazed tiles are the red quarry tiles or the granite looking porcelain ceramic tiles used in heavy commercial areas.
Tile Density and Moisture Absorption
Tile Density – As the weight or the density increase it becomes a stronger tile.
Moisture Absorption – Again as the density increases the amount of moisture that a tile can absorb becomes less.
Tile density and moisture absorption have an indirect relationship to each other. As the density of the tile increases the moisture absorption rate becomes less. Tile density and moisture absorption are important to understand when selecting the tiles for different applications.
Non-Vitreous Tiles – tiles that absorb 7% or more moisture. Suited for indoor use only.
Semi-Vitreous Tiles – tiles that absorb from 3% to 7% moisture. Suited for indoor use only.
Vitreous Tiles – tiles that absorb less that 3% moisture. Referred to as frost resistant tiles but can not be used in exterior areas where freeze thaw conditions could cause tile cracking.
Impervious Tiles – tiles that have less than .5% moisture absorption. These tiles are frost proof and can be used in exterior areas or on the outside of building facades.
Bicottura - It is an Italian word meaning "double fired". The clay
body is fired on the first pass through the kiln, and the glaze is
applied and fired on the second pass through the kiln. This process is
only being used today for decorative wall tile products.
Monocottura – It is an Italian word meaning, "single fired". The tile passes through the firing process one time at a temperature of 2200 degrees. Monocuttura tiles have denser bodies and harder glazes than Bicottura tiles.
White Body Tile versus Red Body Tile
The color of the body is determined by the color of the clay used by the manufacturer that is available in their geographic region. Look at the body of the tile to see if the color is red or white. The quality of the tile is more related to the quality of the manufacturer not the color of the body.
Wall Tile Trims
Bullnose – This is the most used trim shape for wall tile
installations. Wall tile bullnose is sometimes referred to as surface
cap. It has one rounded finished edge on the tile and can be used
horizontally or vertically. For a 4" x 4" tile the industry number would
Corner Bullnose – It has two rounded finished edges on the tile to be used to complete the corner where the horizontal and vertical bullnose meet. Generally you use only 2 – 3 pieces for a bathtub enclosure. For a 4" x 4" tile the industry number would be SN4449.
Stack-on Cove Base – This cove base provides a coving on the bottom and a flat edge on top to continue with more wall tile up the wall. For a 4" x 4" tile the industry number would be A3401.
Rounded Top Cove Base – This cove base has a rounded finished top like bullnose and is used as a cove base in areas that will not have wall tile installed above it. The industry number would be S3419.
The above trims are the most commonly used. There are many other specialty trims available that will only confuse you. Your tile installer will be able to look at your installation and know what trims will be needed.
Floor Tile Trims
Some manufacturers do not provide trim pieces for their products.
There are many other ways to finish off the job; Corian, Marble,
Granite, Wood, Metal and plastic trim accessories.
Bullnose – It has one rounded finished edge on the tile to give a nice finishing touch. Sometimes it is also used as a substitute for cove base.
Corner Bullnose – It has two rounded finished edges on the tile to be used to complete a corner.
Sanitary Cove Base – It has a rounded finished top like a bullnose to cover up the body of the tile.