Whether composed of ceramic, porcelain or some other material, tile’s hardness is a significant factor. It’s important to understand the PEI rating.
Understanding PEI Rating
The PEI (Porcelain Enamel Institute) rating helps you choose the best tile for a given location. This is important because tiles made for walls and floors are not interchangeable. Floor tiles tend to be thicker, tougher, and rougher than those made for vertical surfaces. A homeowner who mistakenly installs the wrong tiles on a floor will soon have a mess that must be taken up and replaced.
The PEI rating ranges from 0 to 5 and is a measure of how well a tile’s glazing resists abrasion. It gives insight into a tile’s hardness and durability, but not other features, such as its slip-resistance or fracture strength. A machine with steel ball bearings is rotated against a tile until visible signs of wear are present. Tiles with a PEI rating closer to 5 are better suited to foot traffic, while those with a low rating are better for decoration or low-traffic areas.
There are five basic PEI ratings:
- PEI 1: This tile is only suitable for flooring in areas with light traffic where no shoes are worn. It’s also appropriate for walls.
- PEI 2: This rating designates tile appropriate only for light residential traffic from soft-soled shoes. It’s not recommended for stairs, entrance halls, etc.
- PEI 3: Tile with this rating is recommended for any residential use, including kitchen countertops and floors. It’s also suitable for light commercial use but not for business entrances.
- PEI 4: This rating designates tile appropriate for medium commercial and light industrial use, including in restaurants and hospitals.
- PEI 5: Tile with this rating is suitable for areas subject to heavy traffic, dirt, and abrasion where maximum performance is necessary. This includes public buildings and shopping malls. Tile in this category is not normally used in the home.
Ceramic vs. Porcelain Tile PEI Rating
Ceramic and porcelain tiles are both made of a kiln-fired red or white clay, but slight differences in the production process yield a dramatically different result.
Ceramic tiles typically have a PEI rating of 0 to 3 and are easier to cut and less expensive than porcelain. However, they are more water-absorbent than porcelain, making them vulnerable to frost. Most porcelain tiles have a PEI rating of 5. Porcelain tiles are made of compressed clay and are denser than ceramic tiles, making them less water-absorbent and better resist frost.
How to Find the PEI Rating
Sometimes, a tile’s PEI rating isn’t easy to find. The law doesn’t require a manufacturer to publish it. Some manufacturers’ sale sheets just suggest the best room for the tile and don’t list a PEI rating. It may take some investigative work on the part of the buyer. The PEI might be found on a document that shows the tile’s technical specifications.
Remember that these ratings do not speak to a tile’s quality or value. They simply designate its durability and appropriateness for a particular use. Professionals who deal in tile flooring can advise you on making your purchase and handle the installation.