With more than 50 years’ experience in the local and international flooring industry, Denver Coleman, Chairman of Polyflor SA, answers questions posed by installers, architects and readers. In this issue, he discusses flooring considerations for heavy traffic areas.

“I need a floor covering for a commercial installation that will be subjected to very heavy traffic. What should I be looking for?” Esme Jansen, Cape Town

Before considering the floor covering, here are a few fundamentals that need to be carefully observed to ensure a floor that is exposed to heavy traffic lasts and keeps looking good:
1. A good Class 1* quality screed is essential. Hardness, smoothness and levelness will have an impact on how your flooring performs.
2. In reality, with today’s fast-paced building environment, very few Class 1 quality screeds are produced. We therefore highly recommend using a self-leveller to ensure the quality and consistency of the screed. It is also important that the self-leveller is of superior quality and able to reach hardness levels of a minimum 25mpa. The self-leveller should be applied with a minimum average thickness of 5mm. An inferior self-leveller will powder on corners and landings under heavy traffic.
3. Critical to the process is safeguarding against undue moisture below the screed surface. Moisture that rises after installation will break down the bond of the adhesive used and will affect the self-leveller, causing the floor covering to bubble, lift or break up. We highly recommended that a moisture barrier be applied to combat any uncertainty and moisture issues that may arise.

Once you are certain that your screed is of Class 1 quality, is level and moisture free, there is a vast choice of floor covering options for high traffic areas. Vinyl is a natural choice and options are best classified into two categories:
– Homogeneous or solid vinyl is a product where the decoration is evident throughout the construction of the product and indicates long-wear capability, provided the product has an adequate PVC content and is not filled with large quantities of chalk (calcium carbonate) filler. While the use of a thicker material will delay the failure or wearing of the floor, a level sub floor will enable a good quality 2mm product to easily sustain heavy traffic.
– A heterogeneous or layered type construction is where the top pattern/decoration is not evident throughout the construction of the product and it is protected by a hard-wearing surface or a strong, thicker wear layer.

Analysing the expected traffic of the floor
A detailed analysis of the expected traffic is always recommended when choosing your material and ensuring you have the correct adhesives and sub-floor. Wheeled traffic demands special floor preparation as it will exacerbate the stress on the floor product and cause disturbance to the adhesion and screed. The weight of the wheeled traffic needs to be considered as extreme heavy weights add additional stress or torque where the wheels turn while pushing the load. One needs to take into account the type, size, composition and diameter of the wheels as this plays an important role in the ability of the flooring material, adhesive bond and screed surface to withstand the stress and point-load.

It may be necessary to consider specific adhesives in high-traffic areas. Options include contact adhesive or two-part polyurethane adhesives and these need to be matched with the floor covering in terms of compatibility, ease-of-use and conditions.

Safety flooring is an extremely hard-wearing floor but has not been discussed in this article, as there are many other factors that need to be considered when installing safety floors.

*As per SANS 0155 1980 ‘Accuracy in Buildings’, a Class 1 screed is defined as: ‘Permissible deviation at any point under a 3m straight edge placed level in one direction, is no greater than a maximum of 3mm’. Your best bet to achieve this? Specify a self-leveller; specify at least a 5mm thickness (we recommend assessing the substrate to determine what thickness is required to attain an average of at least 5mm).

For more information, visit www.polyflor.co.za or call +27 (11) 609 3500.