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What is Grasspave2?

Grasspave2 is the world’s leading choice in porous paving – a flexible, recycled plastic structure that sits unseen below a real grass surface to allow for the weight of virtually any vehicle while protecting the grass roots. With ADA certification and a compaction strength of 15,940 psi, it has been a favorite for Fire Lanes, Emergency Access, and Parking Areas since 1982. Grasspave2 provides a long-term green paving alternative that can reduce CO2 emissions and filter out environmental toxins through bioremediation.

How does the cost of Grasspave2 compare to the cost of concrete or asphalt?

Grasspave2 may initially be more expensive but because it requires minimal maintenance and will not need to be replaced due to cracking or the long term cost will be fair less. The lifespan for Grasspave2 is over 60 years.

Does grass planted with Grasspave2 require different maintenance than regular grass?

The only difference in how one cares for the grass covering Grasspave2 and a regular lawn is that you cannot aerate it as aerating may cause damage to the structure below.

Can Grasspave2 be plowed in the event of snow?

Of course. Simply add a skid to the corners of the plow blades to raise them and proceed as usual.

Is Grasspave2 ADA compliant?

Absolutely. For a link to our ASTM testing results for Grasspave2 click here (pdf document).

Can Grasspave2 be used for fire lanes?

Yes, our second installation ever was a fire lane in 1982 and since then we have provided product to countless other cities and counties worldwide.

How much traffic can Grasspave2 withstand?

While Grasspave2 is designed to withstand vehicular traffic , one must consider that living grass gets enough sunlight, moisture and limited friction to protect its health. For example, parking in the same spots or frequent passes over the same areas on a daily basis will cause the grass distress. However, Grasspave2 continually protects the root zone so even if the grass blades are damaged by overuse they will recover quickly.

How heavy a load can Grasspave2 support?

Grasspave2 exceeds H20 loading and has a psi of 15, 940 so can support the weight of virtually any vehicle. This is why Grasspave2 has been the leading choice for fire lanes, utility and emergency access roads worldwide.

I’m concerned that Grasspave2 specifies using sand instead of soil. Will grass grow in sand?

Absolutely. Sand can easily compact and become impermeable creating mud, ruts and “bath-tubbing”. Because sand never compacts it remains porous allowing the roots to thrive, providing an excellent medium for growing any vegetation. The addition of our proprietary Hydrogrow (included with every order of Grasspve2) ensures water and nutrient retention at the base course level to expedite the root growth process after installation.

Does Grasspave2 work better with sod or seed?

Grasspave2 works very well. With seed or sod. To achieve the best results with sod, use a thin cut sod or rinse off any excess soil with a hose prior to installation, as excess soil will cause compaction and loss of porosity. Hydrosourcing is most successful when a mulch is used. Avoid using mulch such as straw or pine as they generally do not retain enough moisture.

What types of grass should I use for the product?

We recommend using a deep rooting and hardy species such as Blue, Rye, Fescue, Zoysia or Bermuda depending on your area.

Do pieces of Grasspave2 have to be connected when installed?

There are interlocking male and female connectors along the edges of each roll. If using Grasspave2 for a large installation, you can save time by skipping this step or interlocking only periodically, as the established grass roots will anchor the product. For fire lanes and any emergency access areas, it is recommended that all connections be made to maximize stabilization during the “off-limits” root growth period – in case of emergency.

What is Hydrogrow and what purpose does it serve?

Hydrogrow is a specially formulated polymer designed to rapidly promote healthy root growth for at least one year with regular watering cycles. Included with every order of Grasspave2 can be easily distributed over the base course using
A Spreader.

What type of base course does Grasspave2 require?

The most important aspect of a base course for Grasspave2 and Gravelpave2 is its ability to maintain porosity while bearing weight. When choosing the right gravel to combine with your sand for your road base, refer to our technical specifications for your project refer to our technical specifications and avoid materials that solidify over time, losing porosity.

What depth base course does Grasspave2 require?

The depth of base course required is entirely dependent on the application. It is crucial that our Technical Specifications are referenced, and municipalities consulted for areas such as fire lanes, as these requirements vary. Overall, a general guideline would be an equivalent depth to the requirements for 2” of asphalt.

How is Grasspave2 Installed?

Grasspave2 can be easily installed by a contractor or landscape professional. Roll out the product like carpet, over a compacted, porous 50/50 base course and our specially formulated growth enhancer, Hydrogrow. Fill the rings with sand, finish with sod or seed and wait until roots are completely established (generally around 2 mowings) before use. For specific instructions on how to Install Grasspave2 please refer to our installation Instructions.

What is the product cost of Beachrings2?

Contact us directly to get a quote.

How wide should a Beachrings2 mat be to fit a wheelchair?

We recommend at least three tiles wide (3.9ft or 1.2 m) or wider. Beachrings2 mats that are two tiles wide (2.6 ft or 0.8m) can accommodate pedestrians and strollers.

What are the product dimensions of Beachrings2?

An individual Beachrings2 tile is 40 cm by 40 cm (15.75 inch by 15.75 inch). Please visit the pre-assembled roll sizes page for convenient shipping rolls.

What is the difference between Beachrings2 and the competitors?

Beachrings2 can be re-rolled after use. Beachrings2 is extremely lightweight compared to modular systems. Beachrings2 comes in 3 colors, blue, tan, and gray. Beachrigns2 can support the weight of cars and golf carts.

Why Beachrings2 instead of a Beach Wheelchair?

Beach wheelchairs are great and provide great access for the disabled. However, Beach wheelchairs are large and hard to store. Beachrings2 are light, portable, easy to store and provide access to an unlimited amount of people wheelchair bound, pedestrians, strollers, and even light automobiles. Beach wheelchairs are very expensive and provide access to only one person at a time.

What is Beachrings2?

Pronounced “beach rings two,” Beachrings2 is a portable, reusable boardwalk (mat) system, for comfortable, stable, and slip-resistant access over sand and mud.

What is the installed cost of Slopetame2?

The installing cost varies a lot depending on the size of the installation and geographic location.

What is the product cost of Slopetame2?

ISI can’t give an exact price, that has to be done by our manufacture’s representative. Slopetame2 is usually more expensive than a simple mat and less expensive than a gabion or retaining system.

What are the product dimensions of Slopetame2?

The individual Slopetame2 rings are one inch deep and two inches in diameter. The product itself comes in nine different roll sizes ranging from 108 sq. ft. to 538 sq. ft.

What is the difference between ST2 and the competitors?

Slopetame2 is the only combination product available – a three dimensional containment system with fabric backing for immediate and permanent protection.

What is Slopetame2?

Slopetame2 is unique erosion control system with integrated rings, grid, bars and injection molded fabric.

What is the installed cost of Draincore2?

The installing cost varies a lot depending on the size of the installation and geographic location.

What is the product cost of Draincore2?

ISI can’t give an exact price, that has to be done by our manufacture’s representative. Draincore2’s superior performance and initial quality place it on he high end of composite drainage layers.

What are the product dimensions of Draincore2?

The individual Draincore2 rings are one inch deep and two inches in diameter. The product itself comes in nine different roll sizes ranging from 108 sq. ft. to 538 sq. ft.

What is the difference between Draincore2 and the competitors?

Draincore2 can move water at 42 gallons per minute per foot-width. Draincore2 is flexible and can be shaped without expensive connectors, T-joints, or clamps.

What is Draincore2?

Pronounced “drain core two,” Draincore2 is a high volume drainage layer capable of withstanding heavy loads in direct contact.

What is the installed cost of Rainstore3?

The installing cost varies a lot depending on the size of the installation and geographic location.

What is the product cost of Rainstore3?

ISI can’t give an exact price, that has to be done by our manufacture’s representative.

What about silt build-up in Rainstore3?

Silt is prevented from building up in Rainstore3 by using proper pre-filtration, such as catch basins or sediment filters.

Can Rainstore3 be inspected after it is installed?

Yes, by installing maintenance ports during installation. Download RS3 Maintenance Guide in pdf.

How are the Rainstore3 cells installed?

They are installed by lifting by hand (1 meter or smaller) or using a lifting tool and a back-hoe.

How are inlet/outlet pipes attached to Rainstore3?

They are attached by forming a “boot” with the fabric or liner and securing with a hose clamp.

What goes above the Rainstore3 cells?

A layer of Geogrid and a minimum of 12 inches of compacted roadbase.

What goes below the Rainstore3 system?

A layer of geogrid goes on top of the existing, leveled soils and below the Rainstore3 System.

What keeps the soil from entering the Rainstore3 cells?

The entire Rainstore3 system is wrapped in a geotextile fabric or a PVC liner to keep soil from entering.

Why is Rainstore3 better than competitive products such as pipe or arched chambers?

Rainstore3 has the advantages of being virtually any depth, holding more water, using less stone, and having a lower overall installed cost.

How much water does Rainstore3 hold?

Rainstore3 is 94% void area so each cubic meter of Rainstore3 holds 250 gallons. One unit holds nearly 25 gallons.

How strong is Rainstore3?

Rainstore3 has been laboratory and field tested to H-20 loading (bridge loading).

What are the product dimensions of Rainstore3?

The basic Rainstore3 part is a square 40 inches (1 meter) x 40 inches (1 meter) x 4 inches (0.1 meter). These basic units may be stacked to form cells at any depth between 4 inches (0.1 meters) and 7.9 feet (2.4 meters). These cells are placed side by side to create storage volumes any length or width (in 1 meter increments).

What are the common applications of Rainstore3?

The water either percolates into the ground (retention) or is allowed to leave Rainstore3 at a controlled rate (detention). It may also be used to hold rainwater for use at a later time for such uses as irrigation (water harvesting).

What is Rainstore3?

Pronounced “rain store three.” Rainstore3 is a plastic structure used to store water underground. It is commonly used under parking lots as an “underground pond” to hold rainwater during and after a storm.

What is the installed cost of Gravelpave2?

The installed cost varies depending on the size of your installation and geographic location.

What is the product cost of Gravelpave2?

To get a quote for any of our products, either call us at (303) 233-8383, fill out our Estimator form, or find a local representative in your area.

How is Gravelpave2 maintained?

The product requires very little maintenance when installed correctly. The areas of the installation that are the most frequently trafficked may require attention if aggregate has worked its way out of the rings. Maintenance can easily be done by brooming the stones back into place or by replacing any small amount lost if necessary and should only require attention once or twice a year. If a bonding agent is desired, contact us for recommendations.

Can we plow Gravelpave2?

Yes, all of our installations across the country that face snowy conditions, are plowed on a regular basis. We recommend using skids on the corner of the plow blades to raise the blade and keep it from coming into contact with the gravel and potentially damaging the installation. Many plows already have skids or a flexible plastic/rubber piece on the bottom of the blade that protects the blade while plowing asphalt streets and can be used very easily on the Gravelpave2 system.

What is the installed cost for Gravelpave2 vs. Asphalt/Concrete?

Gravelpave2 is generally 10-15% higher than hard paving surfaces. However, using Gravelpave2 can eliminate the need for stormwater drainage and collection systems which could provide a significant savings over asphalt or concrete. The maintenance of Gravelpave2 over a 15-20 year life span is so minimal that it can produce an additional savings of 40% over traditional hard surface paving materials that require constant resurfacing.

What is the Recommended Maximum Slope for Gravelpave2?

5% for Fire Lanes, 8% for Cars and Light Trucks, and 15% – 20% for Golf Carts, Pedestrian Paths, and Trails.

How much traffic can Gravelpave2 withstand?

Gravelpave2 is designed to withstand high frequency traffic on a daily basis.

How heavy of a load can Gravelpave2 support?

With a pounds per square inch (psi) capacity of 5,720 Graspave2 can support any load that is legal to drive on the street. The highest truck tire pressure allowed to drive on the roads is 120psi, fire truck outriggers are only around 81psi. Gravelpave2 is designed to transfer the surface load to the subbase which should be designed to a depth that will support the anticipated loads.

How are parking spaces delineated on a Gravelpave2 lot?

There are a variety of effective methods for delineating parking spaces on a Gravelpave2 installation most effective way to delineate parking spaces on a Gravelpave2 installation is through the use of concrete tire stops. Other methods, such as pouring concrete striping, are possibilities but the tire stops remain the easiest and most effective.

What type of base course does Gravelpave2 require?

The composition of the base course is outlined in our specifications as a 3/4″ minus sandy gravel compacted to 95% modified proctor. The base should allow enough void space for water to percolate. If you intend on using a material that will seal tight once compacted (such as limestone) you must add a 30% mixture of sand to create the required void space.

What depth of base course does Gravelpave2 require?

That depends on the application, as Fire Lanes generally require at least 12″ whereas Pedestrian Walkways may require nothing over sandy gravel soils. A good comparison is the equivalent requirement for two inches of asphalt, for the identical application in your area. Many questions can be answered by our technical team at Invisible Structures: (303) 233-8383.

How do I lock Gravelpave2 together in the field?

There is a clip system along the edges of the Gravelpave2 product. When rolling the product into place align the male and female connectors from each roll next to one another and snap together. The product is shipped with eight inch pins and washers that are nailed inside the rings at a rate of four per square yard with special attention being paid to the seams. Additional pins are available at a cost of $.20 per pin.

What size and type stone should I use as fill material for Gravelpave2?

The important characteristics of the stone are that it is small (3/16″), washed, angular and hard. Small angular stone will lock together in the rings while large or rounded stone will migrate out of the rings into the surrounding area. The fill material must be a hard stone – any soft stones, such as dolimite, will break down into a dirt/mud mixture and will not remain porous. Please view our fill page for more information.

How is Gravelpave2 installed?

Gravelpave2 is installed over a sandy gravel base course at a similar depth to what would be specified for two inches of asphalt. Once the base course is down and compacted, check for porosity by using a hose and making sure the water drains away. Then, the Gravelpave2 is rolled out and nailed into place using the provided nails and washers every six rings – you can use this chart for a pinning instructions. Finally the product is back filled with small, clean, and angular aggregate 1/4″ above the rings.

What are the products dimensions of Gravelpave2?

The individual Gravelpave2 rings are one inch deep and two inches in diameter. The product itself comes in two different roll sizes ranging from 108 sq. ft. to 430 sq. ft. Whatever the size of the project, either an Invisible Structures technical specialist or one of our representatives in the field will be able to assist you in making sure you get the right amount of rolls for your job.

What is Gravelpave2 Porous Pavement?

Pronounced “gravel pave two,” Gravelpave2 was the first aggregate porous paver on the market and still the World’s favorite – a 100% recycled plastic sub-surface reinforcement structure (available in three natural colors and black), with a fabric backing that can never be removed. Its trademarked fabric backing not only keeps the decorative aggregate in place, it is a dust and weed inhibitor. Sold in easy to install rolls that are flexible and easy to trim with pruning shears, Gravelpave2 is also the strongest on the market at 5,700psi and can support virtually any vehicle. It’s also ADA compliant.

Can I seed or sod over the product?

A very good stand of grass may be achieved through hydroseeding with wood or paper. Mulches such as straw or pine needle should not be used when seeding because of their low moisture holding content. Sod can be used as long as it contains very little soil which may compact and kill the grass with use. A sod that has been washed, cut thin (1/2 inch maximum soil thickness), or grown in sand or sandy loam is acceptable.

What types of grass should I use in the product?

Use a species that is both deep rooting and hardy. Generally a Blue/Rye/Fescue mix in northern climates and Zoysia, Fescue, or Bermuda types in southern climates.