Porcelain tiles are tough, very durable, nonporous, and resistant to rust. They are more wear and damage resistant than ceramic tiles. Ceramic tiles are almost always finished with a glaze that contains the color and/or pattern. Ceramic tiles have a relatively high water absorption and are a bit more fragile than porcelain tiles.
PEI stands for the Porcelain Enamel Institute that rates how durable a tile is. The range is from 0-5, 5 signifying that it can withstand heavy foot traffic and 0 signifying it is not suitable for any foot traffic.
Class 0 - No Foot Traffic
Best not to be considered for flooring, only for wall design.
Class 1 - Very Light Traffic
Can be considered for flooring, if bare feet and stockings are the only foot traffic it will come in contact with (eg. personal bathrooms)
Class 2 - Light Traffic
Light foot traffic such as flat shoes or slippers is acceptable for this type of tile; can be used in upper level bedrooms and/or bathrooms.
Class 3 - Light to Moderate Traffic
An acceptable choice for any part of the house for flooring, as long as it is not in danger of extremely heavy traffic.
Class 4 - Moderate to Heavy Traffic
These types of tiles can withstand heavy foot traffic areas in your home, such as entryways, countertops, bathrooms, and kitchens.
Class 5 - Heavy Traffic
Can be considered for all areas of your home or business. This tile is the most study type of tile in the industry.
When selecting tile for your bathroom remodel, it is important to visualize how much foot traffic your tile will encounter. If it is a master bathroom and only a few people will be walking on it, usually in your bare feet, you can use a variety of fragile and/or sturdy tile options. Glass makes a great design piece for either a sink backsplash, or in the inside of your shower or tub. For flooring, you will want something with low absorbency, such as natural stone that has been sealed with an enhancement sealer.