1. What is a PEI rating?
PEI is a measurement of abrasion resistance, meaning how much “rubbing” it takes to physically impact the look of the tile. The test is scored on a scale of 1 to 5 and each value represents a durability to withstand increasingly more demanding traffic.
CLASS 1, Very Light Traffic – CLASS 1 tiles can be used on all indoor wall applications, countertops such as bathrooms, and very light traffic residential bathroom floors. These tiles are not recommended for any area that will have any constant or heavy floor traffic.
CLASS 2, Light Traffic – CLASS 2 tiles can be used on all indoor wall applications, interior countertops applications, and light traffic residential bathroom floors. These tiles should not be used in areas such as kitchens, entryways, stairs or areas with heavy traffic.
CLASS 3, Moderate Traffic – CLASS 3 tiles can be used on all indoor wall applications, all interior countertop applications, and all residential interior floors. This tile should not be used in commercial applications.
CLASS 4, Moderate to Heavy Traffic – CLASS 4 tiles can be used on all indoor wall applications, all interior countertop applications, all residential interior floors and all light commercial applications, such as restaurants and lobbies. This tile should not be used in heavy commercial applications.
CLASS 5, Heavy Traffic – CLASS 5 tiles can be used on all indoor wall applications, all interior countertops applications, all residential interior floors and all heavy commercial applications, such as airports, shopping malls, supermarkets, etc. This tile is an excellent choice for industrial applications where extreme durability is required.
2. What does the COF of a tile mean?
The Coefficient of Friction (COF) of a tile is a measure of the “slip resistance” of a tile. it is important because ratings above a certain number comply with the Americans with Disabilities Act (ADA) and can be used in commercial areas or public areas. There are two ratings – STATIC COF and DYNAMIC COF.
STATIC COF – This is the force required to START something moving. If a LOT of force is applied it will cause one to slip. The Static COF test shows the amount of force needed JUST BEFORE one slips. To pass ADA the test must be done on a WET tile and the resulting rating must be greater than 0.6.
DYNAMIC COF – This is the force required when something is in motion. The Dynamic COF test shows the amount of force needed just before one would slip WHILE already in motion. To pass ADA the test must be done on WET tile and the resulting rating must be greater than 0.42. Based on the fact that this is a rating used only in the USA, many factories throughout the world do not test their tiles for COF. In some cases, we might have to send a tile out to get the COF rating.
3. What is Decoration?
Decoration is the process to get the ink on the tile to form the desired image (for example -Travertine image, Marble image, Wood image, etc.). The most common types are:
Screen Print – the same image on every tile
Rotocolor Print – a very large picture (2’x6’) that has a small piece of the picture placed on each tile thus giving more variation in the final tiles; similar to a random piece of a puzzle in low resolution.
Inkjet Print – a computer database holds an exceptionally large number of images that are printed on the tile just like a paper printer. The final image on the tile is the highest variation of the image. The final image has the best contrast between light and dark; imagine a random piece of a puzzle in high resolution. Inkjet print prints into the ridges on the tile and prints to the very edges for a natural look in the finished tile.
4. How can I judge the Quality/Complexity of the image on the tile?
When looking at the tile, ask yourself the following questions: Does the image go all the way to the edge of the tile? How many different colors are blended into the image? Are the transitions from one color to the next color sharp or blurry? Is there a good variation in the image from one tile to another tile in the carton? Is the image a believable reproduction of stone or wood?
5. What is Shade?
When the ink is mixed and applied to the tile, there could be a slight variation in the color after the tile goes through the kiln. The factory will separate these slight shifts in “color” and designate them as different “shades” and then each shade is indicated on the carton.
6. What is Caliber?
When the tile goes through the kiln, the heat removes the moisture from the tile and it will shrink by 7% to 10%. As conditions change in the factory (humidity, heat) and inside the kiln (temperatures fluctuate slightly inside the kilns), the tiles will shrink at different percentages and could be slightly different sizes. Like shade, factories will separate calibers and identify them on the cartons.
7. What is Rectified?
A rectified tile has a process AFTER it is cooked, the edges of the tiles are all cut to a 90 degree edge, and this allows the factory to cut every tile to the same exact size (no caliber differences). With 90 degree edges and one caliber, the installer can install the tiles with a “razor thin” grout line. The benefit is a floor that is more tile and less a grid work from grout lines, leaving less maintenance on the new floor.
8. What are Water Absorption Levels?
The test for water absorption is a standard test for tiles. It tells you the porosity of the body of the tile or how likely water is to seep into the body. The more water that seeps into the body the more likely the tile is to crack if the temperature drops below freezing when the tile is wet inside. It does not matter for indoor installation, but for outdoor installation only use porcelain which has the lowest level of water absorption of less than 0.5%.