Grasscrete - permeable and sustainable grass cover with built-in SuDS

For architects looking for an extension of the green envelope, turning the car parking areas of any building development, commercial or housing development, into a sustainable green car park provides the perfect combination of green vista with proven SuDS performance.

Yorkshire based Grass Concrete Ltd has been installing sustainable environmental solutions for more than fifty years. Grasscrete, a permeable grass paving system is frequently used for flood alleviation, SuDS ponds and grass covered carparking.

The permeability features of Grasscrete grass paving directly address SuDS issues. Hard landscaped areas can often provide high volumes of rain run-off into the sewer network especially during heavy flash floods. A more permeable grass paving mitigates surface water run-off and its implications for the local storm water network.

With the notion that Grasscrete can permeate at up to 90% the rate of natural grass a safe source control can be achieved. The ability to also store water within the system ensures a low risk of ponding, until the ground can naturally re-charge is a significant plus. Lag time is beneficial in the prevention of flooding and can be extended by introducing an underlying drainage blanket across the full extent of the paved area. The drainage blanket can be used to either attenuate permeation to the water table in areas of otherwise poorly draining ground or it can be a vehicle for rainwater harvesting.

Grass Concrete offers two types of system, Grasscrete and Grassblock. Larger projects favour cast-on site concrete pour to produce Grasscrete. Smaller installations often consider Grassblock, easy to install precast blocks. Both systems are ready to be infilled with top-soil and appropriate grass seeds to suit the environment.

In 2015, when Britain’s top Rugby Union team Saracens FC called for a new car park to be constructed it came with a need to fully complete within the 3-month period between seasons. Leaving just 6 weeks for the Grasscrete installation. The project came with several additional requirements; the need to incorporate an aisle of EV charging points and to provide for heavy plant and vehicle access to Phase 2 to be constructed at a later date.

With the majority of the area designated for car parking the 76mm thick Grasscrete GC3 was selected for traffic up to 4.3 tonnes. Here spectator movement was aided by walkways defined by gravel infill in lieu of topsoil and grass.

Access to the future phase 2 area was achieved by a link road within the car park that was upgraded to the 150mm GC2 system, which enabled 40 tonne vehicle loads.

This Phase 2 began in 2019 with the construction of a new Outside Broadcast hardstanding area again using the heavyweight GC2 system, followed by a further 2 phases of installation to extend the GC3 parking areas from the original phase.

Now fully operational these large areas of Grasscrete, provide the ideal combination of engineering performance together within a naturally grassed landscape.