FAQ

After installation, care is similar to your regular lawn care.  Water, fertilize and mow as you would the other lawn areas of your landscape.  When the Drivable Grass® mats are properly infilled, the wheels of your lawn mower will ride on top of the surface while the grass is cut 1-3 inches above.  See how easy it is to mow Drivable Grass®..

Drivable Grass® can move with frost heave in a freeze thaw cycle with no cracking. The product’s interconnecting grid is made from an engineered polymer that remains flexible even in low temperature conditions. When installing Drivable Grass®, do not use frozen materials or materials mixed or coated with ice or frost. Do not build on frozen, wet, or muddy subgrade and ensure proper drainage to avoid standing, freezing water.  Deicing agents, such as rock salt, should be avoided as they will damage concrete over time.

Drivable Grass® can be manufactured with air entrained concrete for cold weather conditions upon request.

When Drivable Grass® is properly installed, shoveling or snow plowing should not be an issue. Snow plow operators should be educated as to the type of surface they are plowing over prior to beginning snow removal. Teflon runners placed under the snow plow blade are highly recommended. The snow plow operator should be advised to keep the blade up a bit. A 2” to 3” layer of snow left on the Drivable Grass® mats after plowing will rapidly melt, even in cold conditions, due to earth temperature warmth emitting through the product voids and/or solar radiation. Melting snow will infiltrate and will not result in icy conditions on the mat surface in the event of a refreeze.

For sites that will require the use of heavy-duty snow plowing machinery, install concrete curbs and/or strips as a level guide for the snow plow blade prior to installation of Drivable Grass® paving mats. Drivable Grass® should be depressed below the top of the curb/strip to protect the product from the snowplow blade.

Drivable Grass® concrete paving system is a simple do-it-yourself project for the homeowner.  Installation is similar but easier than pavers and is explained in detail in our do it yourself installation brochure available wherever our Drivable Grass® product is sold or via our website soilretention.com.  Installation is more forgiving since the product comes in a mat instead of small individual pavers that require specialized equipment.

Any contractor that installs pavers can easily install Drivable Grass®.  The ground preparation is similar to pave stones.

Talk with your local nursery or landscape supplier for a recommended grass in your area.  They will be the best source of local information concerning the best grass variety to grow in your area and withstand the desired traffic levels.  In general, for high traffic installations self repairing grasses are recommended.  Here is a link for grasses: http://www.american-lawns.com/.

By “organic material” we mean finely ground, well screened composted products such as composted manures, mushroom compost or green-waste compost.  It is important that the material be finely ground, not the size that would be used for mulching planting beds.

Along with normal lawn grass, Drivable Grass® can be filled with sand, gravel, colored rock, or artificial grass.  We recommend an angular stone for stability.  In low use traffic areas, you can also lay sod over the product.

Drivable Grass® is recommended for slopes as steep as 12% with vegetated infill.  Installation of Drivable Grass® for traffic loading on grades steeper than 12% must be evaluated by a qualified engineer or architect.

Yes, Drivable Grass® can be placed on a hillside as long as the slope is stable and Drivable Grass® is not acting as a retaining wall. If the intention is to vegetate Drivable Grass® on the hillside (i.e. Hydroseed the installation), a basic biodegradable erosion control blanket can be placed directly underneath Drivable Grass®. If vegetation is not required / desired, a filter fabric should be placed underneath the Drivable Grass®.

Irrigation can be done by an overspray pattern along the sides of the installation.  For large installations, where perimeter coverage is not enough, irrigation can be run under the Drivable Grass® with cut or removed muffins allowing for pop-up riser operation.  There are also advanced underground drip systems & rotors available.  Contact your local landscape irrigation supplier for details.  See this video:  Irrigating Drivable Grass®

Drivable Grass® is constructed of 8000 PSI concrete.  It was designed and tested for use as emergency vehicle access at large commercial and residential projects so it can easily withstand the pressures of standard residential traffic including your heavy RV.  Proper ground preparation is the key to a successful project.

In our do it yourself installation brochure, found wherever Drivable Grass® is sold or on our website soilretention.com, you will find a chart which gives you the manufacturer recommended base depths dependent upon your intended use and soil types.

In paving design, an aggregate base is a layer of hard angular material made up of crushed rock and/or sometimes recycled concrete that is placed on native soil to provide a stable “base” for the paving surface and to absorb loads.  A typical “base” or “road base” is comprised of materials ranging in size from 1″ – 3/4″ pieces down to small particles like very fine sand.  In some areas it is known as “Crusher run”.

Sharp sand is also known as builder’s sand or washed concrete sand.  It meets the specification of ASTM C-33.  Sharp sand has the same properties as the aggregate base, sharp angular edges and decreasing smaller particle sizes.  The top particle size is rather large, about 1/8 inch in diameter and the smaller end, zero percent passing a #200 sieve.  Do not use play sand, mason sand, or sand box sand.

Generally, Drivable Grass® should always be contained using hard containment such as a concrete header or landscape paver edging.  In applications where the direction of travel is straight in/straight out, containment such as embedment in an established lawn or landscape berm may be an acceptable alternative.

Drivable Grass® can be cut along the internal grid pattern using a cold chisel, utility knife or screwdriver.  For curves and precision applications you can also cut the concrete product with a standard concrete saw blade.

The flexibility of Drivable Grass® allows it to be used on contour landscape designs; therefore you’re not limited to a flat plane as you are with concrete or pavers.  Also due to its flexibility, you will not have an issue with a cracked drive surface like you would with concrete, asphalt, or pavers.

Drivable Grass® is produced in 2’ x 2’ mats allowing for easy installation.  Currently, Drivable Grass® is available in Shilo Tan, Grey, and Earl Grey, (Shilo Tan and Earl Grey are available in the CA plant only), colors.  For large installations feel free to contact us concerning producing the Drivable Grass® mats in custom concrete colors.  Drivable Grass can also be stained with custom colors.

Drivable Grass® allows the storm water to filter through it into the subsurface, and keeps the storm water on your property and in your water table.  This allows contaminants (vehicle drippings, car wash chemicals and such) to filter through the aggregates installed below the product so that they do not enter the local drain system and contaminate the local waterways and oceans.  Further, grass also bio-degrades pollutants.  Concrete, asphalt, rooftops, and other non-permeable surfaces don’t allow water to get back into the water table as it did before your property was developed.

Since Drivable Grass® provides a stable structure to your landscape areas while retaining the aesthetically appealing look of a carefully landscaped area there is an expected advantage in “curb appeal” over standard concrete or asphalt surfaces.  Also, Drivable Grass® significantly reduces the Heat Island effect due to its cool characteristics.