Client: Municipality of Keltern, Germany
Object: Creek bridge, public footpath.
Assignment: Slip protection for bridge with wooden plank covering.

Substrate: Wood, larch.

Antislip Solution: Non-slip floors
Slip Resistance: Slip resistance class C and R11
Class C:      DIN EN 16165 – Angle of inclination ≥ 24°
Class R11:  DIN EN 16165 – Angle of inclination 19°-27°

How is wood made non-slip?

Slippery wooden bridge in public space receives permanent anti-slip protection.

Wooden bridges have existed since prehistoric times, i.e. for 1.6 million years. While at first it was fallen tree trunks that helped to cross streams, swamps and hollows, people soon found a way to literally build crossings with wood. The oldest recorded wooden bridges date back to the Middle Stone Age.

And even today it is impossible to imagine our environment without bridges made of wood, a renewable resource. Brooks and small rivers in rural areas are often bridged with wood, as they fit well into the landscape and the wood can usually be found on the doorstep.

The public bridge made of larch in the municipality of Keltern connects a residential area over the Pfinz. Next to yew, larch is the heaviest and hardest wood among the European conifers. No wonder, then, that larch was used for bridge building. Like all woods, the bridge planks were also slippery when wet. SWISSGriP was commissioned to make the bridge slip-resistant.

This is how wood becomes non-slip:

  1. The edge areas of the surface to be coated are masked with foil and/or adhesive tape.
  2. The wooden planks are subjected to a basic machine cleaning in order to obtain an absolutely clean coating surface. This process is important to ensure adhesion.
  3. Then comes the anti-slip coating: the wooden planks are sprayed evenly with a sprayer. In this case, the wood was sprayed with the anti-slip coating SWISSGriP R11. For smaller objects, the anti-slip coating can also be applied with a roller; this method of working is similar to painting a wall. In this case, the coating is rolled on evenly in a criss-cross pattern.
  4. The drying time is 12 hours, after which the wooden covering can be walked on again. After 5 days, the coating is completely dry and can also be cleaned with mechanical cleaning equipment.