Porcelain Enamel Institute(PEI) Chart
PEI rating helps to classify the durability and functionality of these surfaces with the following system.
This is the weakest of all standard grade ceramic tiles. It’s really only suitable as a wall tile.
This is best for light traffic areas. Again, a great product for wall tiles, but it will also work in residential bathrooms, where foot traffic is minimal.
Grade three is most common in residential building, and perfect for light to moderate
traffic. This makes it a very good choice for all residential flooring, walls, and
back splashes. Some can also be used in light commercial traffic.
This grade is a step above grade 3 tile grades. It’s still a good choice for residential
uses, such as tile floors and countertops, but it can also take the heavier abuse
of light commercial foot traffic, such as you’d find in a doctor’s office.
When it comes to standard grade ceramic tiles, grade 5 is built to take a beating.
It’s mostly used in high traffic commercial areas such as shopping malls and airports.