Wet pour rubber is the EPDM (Ethylene Propylene Diene Modified) rubber granules that form the basis of wet pour playground safety surfacing. Other fixed play surfaces such as Notts Sport Childsplay are polypropylene, but some ChildsPlay systems do incorporate the use of rubber crumb.
The majority of black, wet pour playground surfaces are made from recycled car tyres. This is a positive step, as disposing of old car tyres has always been difficult and had adverse environmental impacts.
There is both a mechanical and chemical method for reclaiming the materials that the rubber granules are made from:
- The mechanical method involves cutting the tyres into pieces and passing them through a mechanical grinder. A number of passes are required in order for the tyres to be cut down into small enough pieces to make them workable when they are laid as wetpour playground safety flooring. Following this, large magnets remove any metal contaminants from the rubber crumb.
- The chemical method involves the tyres being melted over metal gauze. The molten rubber is allowed to pass through the gauze and into cold water. The temperature change caused by the water rapidly cooling the molten rubber, makes the rubber form into granules. The size of the rubber granules is determined by the size/gauge of the gauze used.
Different sizes of wetpour rubber are used for different applications. For instance the smallest granules (1-2 mm is this correct) are used in the Notts Sport Childsplay 90/120 system, where as medium sized granules (1-4mm) are used in the wearing course of wetpour rubber. The largest sized granules (2-8mm) are used in the base course of wet pour safety surfacing.
Initially rubber crumb was resin bound in pre-cast tiles, which were a common form of playground surfacing. Although it was easier to install, it was very susceptible to vandalism and ultimately ended up costing local authorities/parish councils too much to maintain. Hence one piece, poured wet pour was created. Look at the wet pour page for further information.
Groundwork and Leisure Services (GLS) offer a nationwide installation service for wet pour play area surfacing. Many councils are however, opting to install Notts Sport ChildsPlay system, as they offer all the benefits of wet pour with a higher level of vandalism resistance and therefore longevity. GLS therefore encourage would be clients to consider Notts Sport as potentially the best playground surface on the market.