PEI value of tiles: the essential selection guide for 5 classes

By Osman · Tile and technical specialist at Tegelmonsters

The PEI value of tiles indicates how wear-resistant the glaze is, while the R-value says something about the slip resistance of the surface. Both classifications are independent of each other.

Together, they determine whether a tile is suitable for the space where it will be laid. A poorly matched combination results in a surface that looks beautiful but technically falls just short of the project requirements. Properly interpreting the PEI value of tiles in practice requires knowledge of both the ISO standard and the expected use per room.

Operation & technology

What do the PEI value of tiles and the R-value say about a tile?

The PEI test follows the European standard. ISO 10545-7A turntable with steel ball bearings and abrasive powder loads the glazed surface. The test counts between 100 and 12.000 revolutions. Depending on the number of revolutions without visible wear, a tile falls into class 0 through 5. Class 0 is not suitable as flooring. Class 5 withstands heavy foot traffic.

The German standard DIN 51130 from 2014 applies to the R-value. A test person wearing standard safety shoes walks across an inclined surface with a thin film of oil. The incline increases gradually until the person starts to slide. The angle of inclination at that moment determines the R-class. R9 corresponds to an angle of inclination between 6 and 10 degrees, R13 to more than 35 degrees.

The two values ​​therefore tell different stories. The PEI value of the tiles says something about sustainability. The R-value says something about safety. In the background on wear resistance read how the test protocol works in practice.

R-values ​​R9 to R13 translated into slope angles and typical project spaces, in combination with PEI value tiles. Source: DIN 51130 (2014).

Comparison

Which PEI class corresponds to which usage level?

The classes for PEI value tiles are cumulative. A tile with PEI 5 withstands everything that PEI 1 through 4 withstand, including sand, grit, and trolleys. The choice depends on the frequency of use and, above all, on the amount of abrasive dirt brought in via footwear. This latter point requires attention at entrances, where it is precisely a doormat and a high PEI class that make the difference.

For professional projects, the design team almost always chooses PEI 4 or higher. The European classification EN 14411 links this scale to product group indications such as BIa for porcelain stoneware. Porcelain stoneware is a fully ceramic, fired stoneware group with a water absorption of less than 0,5 percent. Tiles in this group typically achieve a PEI value of 4 or 5, partly due to their dense structure.

A useful point to consider: the PEI value of the tiles determines how long a surface remains aesthetically pleasing. A PEI that is too low may technically last for years, but it will dull sooner in the walking paths. This is particularly relevant in commercial projects, where a dull line between the door and reception becomes visible after just one year.

Practical tips

What R-value is required per room type?

The DIN 51130 scale from 2014 uses work footwear and an oil film as the basis for testing. This makes the values ​​strict: an R11 tile on a terrace still has sufficient grip for safe walkability even under rain and falling leaves. For outdoor spaces without vertical structures, architects usually choose at least R11, sometimes with a textured surface.

In residential projects, the function of the space determines the lower limit. An internal hall is assigned R9 as the base, while a bathroom aims for R10. For construction projects in the healthcare sector, additional regulations apply to the PEI value of tiles and slip resistance: R11 is the standard there in wet disinfection rooms, in accordance with internal quality systems and the performance requirements of the Building Decree.

More technical background on anti-slip and the differences between dry and wet test environments can be found in the explanation of anti-slip valueChoosing an R-value is a trade-off between safety and maintenance budget.

Operation & technology

What does the A/B/C classification mean for bare feet?

The DIN 51097 test uses soapy water instead of oil. A test subject walks barefoot over an inclined plane that gradually becomes steeper. The angle at which sliding begins determines the class. Class A corresponds to a minimum angle of 12 degrees, Class B to 18 degrees, and Class C to 24 degrees. The two standards therefore consider different usage situations.

In practice, a combined designation often appears on technical data sheets. For example, a bathroom tile is tested with R10 and B, a swimming pool surround with R11 and B, and a swimming pool basin with C. The explanation about anti-slip in wet areas describes why the B classification in residential bathrooms has become the de facto standard.

Planning & lead time

How do you combine both values ​​in a project specification?

A good specification starts with the function of the room. Next comes the expected footwear, the cleaning regime, and the requirement from the Building Decree for skid resistance performance. Next, enter the PEI and R-value. The finish is listed separately: matte, satin, or textured. This choice also influences the measured R-value.

In large-format projects, the combination of PEI value tiles and R-value is particularly important, because a high PEI in an XXL tile requires proper substrate preparation. XXL tiles range in size from 100×100 cm to 120×280 cm. Rectification ensures clean-cut edges and thus a narrow joint of two to three millimeters. The technical background of rectification belongs in the same specification block as PEI and R-value.

Maintenance & care

What should you pay attention to during sampling and maintenance?

A number on paper is no substitute for a real sample. Two tiles, both with an R10 rating, can feel different due to the finish and grain size of the surface. The same applies to maintenance: a matte textured surface collects fine dirt faster than a satin variant. Managers only notice this after installation.

With large projects, we often enter the various applications of ceramic tiles The same trade-off applies: an architect wants a specific vision, the manager wants manageable maintenance. A sample set with three variants lined up makes that trade-off concrete. You can read what a maintenance protocol looks like in the cleaning guidelines.

Get started

How do you request a sample pack for your project?

The most frequently asked question our team receives from project managers is: what R-value do we actually achieve with a specific finish, and how does that compare to the PEI value of the tiles? To check this, we send free samples to the project or showroom address. You bundle them per project in the digital Sample Folder, so that colleagues, the client, and the contractor all have the same specifications in front of them. After sending thousands of tile samples, we have noticed that the final choice is almost always made at the project location itself.

Op tegelmonsters.nl/tiles Filter the assortment based on the characteristics relevant to your project: PEI value of tiles, R-value, size, color, and finish. Our manufacturers from Spain and Portugal provide technical data sheets with the complete classification for each finish variant, so you go from paper to a physical sample without surprises.

FAQ