Asphalt is a fossi- fuel product that retains heat, raises the ambient temperature around buildings and thus increases building cooling loads. Asphalt prevents water penetration and thus contributes to flash flooding by overloading storm seer systems. Asphalt does not provide any opportunity for community use during the hours that commerical buildings are in use. Grass paving systems developed in earlier years were made of concrete. These systems were unsuccessful because the roots of grass burned and the plants failed.
Modern grass paving systems are of two types.
In one system, open cells of reinforced plastic are designed to house the roots of the grass. The roots stay cool and the grass thrives. Driving on the grass has no effect on the protected roots, just as moving the blades of grass strengthens and thickens it. In this system, turf is pressed into the open cells. If the roots are above the cells, car wheels will spin the grass off the grass pave structure.