CHOOSING THE RIGHT GRID SYSTEM FOR YOUR PERMEABLE DRIVEWAY/PATHWAY PROJECT (as published in CV Record, March 14, 2012)
While plastic grid systems for stabilizing grass and gravel have been commonplace in Europe for decades, they are now becoming popular in North America with both developers and homeowners. These systems allow them to use grass or gravel to create stable, drivable surfaces for driveways, parking areas and paths.
GO FROM THIS
WITH A PLASTIC GRID SYSTEM FOR STABILIZING CLEAN GRAVEL
The increase in use of these systems in N. America has brought some excellent products to choose from as well as some which should be avoided. Failures have come in the form of fractured plastic, excessive gravel displacement and design failures that don’t withstand the specified use (e.g. turning tires)
EXAMPLE OF A FAILURE DUE TO POOR DESIGN FOR SPECIFIED USE
This fine gravel has become compressed and the delicate shallow cells have been damaged by vehicle use. Product failure is as a result of:
incorrect product for project use – light duty plastic used in heavy duty application
product design only contains gravel in rings and not open areas around rings
incorrect fill (poorly specified gravel – no fines should ever be incorporated into a plastic grid system)
An ideal design incorporates a connected pattern of closed cells, such as those shown here. These closed cell designs contain the entire volume of grass or gravel in a given application and provide sufficient strength to support both pedestrian and vehicular use. Turning tires (the ideal test for a plastic grid system) are no problem on these types of grids.
There are many variables to consider when selecting a plastic grid system for your permeable and stabilized grass or gravel surface. Be sure to consult your local landscape architect/designer to ensure that the product you use is properly matched to your intended use.