How many people walk on the floor daily?

If the number of visitors at your home does not exceed fifty people a day, then you do not need a floor that meets a higher load class. At least that was how the dividing line between floor coverings suitable for residential purposes and for the commercial sphere (offices, restaurants, etc.) was set in the past. Today’s floorings, however, mostly already meet these higher commercial demands "as standard," so you do not need any special equipment. It is sufficient to ensure that the chosen flooring has either the number 23 or a two-digit number starting with three (31, etc.) indicated in the load class column. However, be careful not to confuse the load class, which relates to the wear of the floor from normal use (simplified as frequency of people moving), with the resistance of the covering to impacts with sharp objects.

Let’s start from the beginning, there are three load classes. The class starting with the digit two is intended for residential construction, followed by "three" for commercial loads, and for the demanding industrial segment, a class starting with four must be chosen. Within these classes, there are also degrees, expressed by the second-digit in order – for example, flooring with a load class of 21 can withstand less than flooring marked with class 23. Furthermore, the individual classes overlap, so flooring with class 23 from the residential range is actually equivalent to thirty-one, thus "the weakest" of the series for commercial use (which includes degrees 31, 32, 33, and 34).

"Just fifteen years ago, laminate floors with a thickness of 6 mm were sold that could only manage loads of 21, 22. Back then, it was really necessary to ask the client where they wanted to lay the covering to ensure they weren't placing it in the most heavily trafficked hallway or living space. Today, these floors are more of an exception, as the production of laminate flooring has advanced significantly. The standard is a thickness of 8 mm, and even laminates now begin in load class 23 – 31, so you won’t find anything worse except for exceptions," says Milan Mrkáček, head of regional sales at Kratochvíl parket profi. For instance, under its brand KPP, it offers water-resistant laminate floors from the KPP Euphoria collection, manufactured in Germany, with a load class even of 33.

For maximum load class, flooring must be glued down

The classification of flooring into a load class is determined by two factors, the strength of the top wear layer and the method of installation, which is the primary filter. "No flooring that is installed as a floating or click-lock system starts in load class four because the standard defines the utility properties of the covering also according to the method of installation. And it stipulates that floors in load class four must always be fully bonded. Therefore, with laminate floors, SPC coverings, or vinyls installed as a floating system, you will find a maximum load class within the range of three, i.e., 31 to 34," explains Milan Mrkáček from KPP.

The second mentioned parameter is the thickness of the wear layer. "The differences are not dramatic, for thirty-one, the defined wear layer is 0.3 mm, with thickness 0.4 mm corresponding to class 32. 0.55 mm is adequate for class 33, respectively 42, and higher load classes require 0.7 mm. That is defined by the standard, but some manufacturers have even thicker wear layers," continues Milan Mrkáček from KPP. The highest load class with a wear layer of 0.7 mm is offered, for example, by the Swedish vinyl manufacturer Kährs, while the German company WINEO focuses on vinyls with a wear layer of 0.55 mm, but also offers elastic floors PURLINE, which in the 1500 collection also reach the highest load class at the level of industrial loading. By the way, the bio-floor Wineo PURLINE 1500 could, in exaggeration, be used as a road surface - during testing by a university in Bielefeld, no wear was observed on the floor after 25,000 passes with a 500 kilogram load at a speed of 6 km/h! The excellent durability is positively attributed to the composite bio-polyurethane ecuran, which forms a 0.3 mm thick wear layer.

Industrial loads would be effortlessly achieved by mineral SPC coverings, for example from manufacturers like Arbiton or Kährs, but considering the method of installation with a click-lock system, they only reach "class three." "However, they are definitely suitable for spaces like restaurants or shops," explains Milan Mrkáček from KPP.

For wood, the less, the harder

Wood is a chapter in itself. In wood, load classes are not stated, there is no normative recommendation on where which can be used. The hardness of the wood, which depends on the species itself, is decisive. The value of hardness is determined by the Brinell scale. Oak is considered a medium-hard wood, on the Brinell hardness scale, oak has a coefficient of 3.7 degrees, while beech is essentially the same at 3.8. If a customer truly wants a hard wood, they must reach for exotic types like merbau or jatoba with an average value of 7. "But there is an exception, which is veneered multi-layer flooring, for example, Swedish Kährs in the Life collection," points out the paradox Milan Mrkáček: "When you use oak only as a veneer on a solid hard HDF board, you suddenly reach 5.8 to 6 degrees on the Brinell scale. Thanks to the hard HDF board, on which there is only a veneer of noble wood, these floors from the Kährs Life collection have significantly higher hardness than if you had a floor entirely made of the same wood species at 15 mm thickness."

Do not confuse normal wear with resistance to sharp objects

While before, customers had to monitor the load class and consider whether the covering was suitable for a hallway or "just" a bedroom, today, especially in specialized flooring companies, you won’t encounter poor-quality coverings. They will also advise you on the resistance of the covering to impacts from sharp objects or water resistance. "Exactly, the load class only relates to the wear of the floor from normal use, which sometimes people misunderstand a bit unfortunate. For example, vinyls do not like sharp objects, so if you drag a heavy object, you will scratch that floor. And it doesn’t matter if it belongs to load class 31 or 43, it will get scratched the same way. And those people then feel unfortunate and say, we chose 32 and look how scratched it is... But the load classes indicate the degree of wear from typical usage," advises Milan Mrkáček from Kratochvíl parket profi.