How to properly prepare your site for playground unitary safety surfacing

The longevity of any playground unitary safety surface ultimately depends on the quality of the material and install, but also on the quality of the sub surface it is sitting on. When I say, unitary playground surfaces, I mean poured in place rubber, bonded rubber, synthetic turf and to a certain extent, rubber tiles. However, good site prep and drainage also afffects the longevity of engineered wood fiber as bad drainage speeds up the decomposition time of EWF.

I always get questions like: Why can't I install my bonded rubber right on top of my soil. The answer is that soil will shift over time creating an unstable base for your unitary surface. Also soil contains organics that will degrade, creating cavities in the long run. Also, you have to pay attention to drainage. Water flows downhill, therefore your site has to allow for a little pitch to make sure that water is not staying still under your surface. There are sites that are simply not a good candidate for safety surfacing, such as sites next to a steep hill. These challenges might call for other forms of drainage, such as curtain drains.

Here is a step by step proven formula to make sure you are providing your site prep for your safety surfaces such as poured in place rubber, bonded rubber and synthetic turf.

• Make sure to remove any organics from the soil. All existing mulch must go. Remove all grass. Excavate below the roots of the grass. 
• Procure 3/4" crushed stone with fines. the fines help the stone interlock nicely. Spread the stones. We like a minimum of 3 inches. 
• Compact the stones at 95% compaction using a plate compactor or a roller. Make sure you have at least a 1% pitch from any buildings and towards an area where you want the water to flow. 
• If you would like to add to he compaction, add stone dust to the stones and compact again.