A Guide To Slip Resistance For Timber Floors

Slips, trips, and falls are one of the most common household accidents across the world, and can lead to serious injuries, especially for older people with more brittle bones¹. Every timber coating has something called a slip resistance, which is how slippery the flooring is after the product has been applied. To keep people safe, it’s important to identify the product’s slip resistance so that you know it’s suitable for your particular project.

But before we jump into that, let’s quickly explore how slip resistance is measured, so you have some background information on the process.

How is slip resistance measured?

The Building Code of Australia states that “paths of travel” in commercial buildings must have a slip resistant surface (but this is equally important for homes too). Slip resistance is measured using something called Slip Resistance Value (SRV), which ranges from P1 to P5 with the highest value having the greatest resistance. Within this value is something called a Coefficient of Friction (Cof), which measures the amount of friction between two surfaces. The higher the CoF, the better the slip resistance for flooring.

To help people pick suitable coating products for their flooring, the Australian Government created two classification handbooks:

1. AS4586—Slip resistance classification of new pedestrian surface materials
2. HB 198—An introductory guide to the slip resistance of pedestrian surface materials

The AS4586 handbook outlines four methods of testing to ensure that a floor meets the required slip resistance:

1. Wet pendulum slip resistance test—uses a swinging pendulum with a spring loaded rubber foot, to calculate the floor’s SRV. This is suitable for areas that are likely to become wet, like verandas, courtyards, and roof decks.
2. Dry floor friction slip resistance test—uses a machine with a 9mm rubber slider which moves at a speed of 1m per minute and measures the opposing force on the slider itself. The result is measured as a Coefficient of Friction (CoF), which falls into two classes for the test—D0 and D1—with D1 being the better rating. This test is good for areas that are usually dry, and rarely come into contact with water.
3. Wet bare foot inclining platform slip-resistance—uses an inclining platform and real people to walk up it after having their feet wetted. The platform is raised until slipping starts to occur. The results are in three categories: A, B, C, each based on the angles at which the person starts to slip, and with C being the sharpest angle. This test is another good one for wet areas, like flooring close to swimming pools or changing rooms.
4. Oil wet inclining platform slip-resistance—this uses the same method as above, but with oil instead of water. It’s designed for flooring in industrial and commercial spaces like factories and kitchens, and the results are in five classes: R9 to R13, with the higher end of the scale representing more extreme angles.

As a floor’s coating wears away over time, so does slip resistance. If this is the case, the flooring should either be recoated, or tests recompleted to ensure that slip resistance is up to spec. This is especially true for areas with lots of foot traffic.

How do I choose an anti-slip coating for my timber floors?

Many products include a slip rating that tests them against the AS4586 classification and gives a result for the test. For example, a coating may have been tested using the dry floor friction slip resistance test and achieved a result of D1, making it grippy and safe once applied.

When choosing a timber coating, be sure to consider where you’re applying the coating (it is mostly dry, sometimes wet, or often wet), check which method has been used to test it, and whether the result is a good one. The higher the result, the safer the product.

References

1. Sue Hewitt, 2021, 10 worst home safety hazards and how to fix them, RACV