Pervious concrete can be used in the place of conventional exterior pavements for parking lots, roads, driveways, walkways, sidewalks, paths, courtyards, and sports courts. It is suitable for light to heavy vehicle traffic at low to moderate speeds - including buses, fire trucks, and semis.
Yes! Using site-specific soil infiltration rates the pervious concrete system can be designed to compensate for slow draining soils. From the first flush to capturing all the impervious cover runoff, we can plan, model, and install a system that captures and infiltrates all your stormwater without the need for conventional stormwater infrastructure.
Same as traditional concrete, 30-50 years.
A little bit of common-sense site design can go a long way towards avoiding any clogging issues. Runoff from adjacent areas laden with sediment should not be directed onto the pervious. Short of that normal debris from traffic, trees, and people have little effect on the ability of pervious to drain water. A high-quality installation will allow for 200-700 inches of water to pass through per hour, even if it was 95% clogged it would still allow 25-75 inches of water to pass through per hour. That's more water than even the largest storm event.
Most high quality pervious concrete installations will need minimal maintenance. If the surface should ever clog, cleaning with a power washer and/or a vacuum truck will restore the pervious to its original state. More information can be found in our maintenance manual available on the CMS resources page.
One additional thing to note is that the only substances that can truly clog up pervious concrete installations are chewing gum and asphalt fines, small debris that sheds from asphalt pavement. These asphalt fines get into the air pockets of the pervious concrete, when the surface warms up from the sun they melt, sealing the air pocket, and becoming impossible to remove. Even the strongest vacuum truck will not get them unstuck. We never recommend that pervious concrete be installed adjacent to asphalt without a buffer, as the encroachment of clogging asphalt fines is permanent.
The layer of drain rock, known as a recharge bed, beneath the pervious concrete acts as a detention area, or buffer, to hold water until it has a chance to soak in. The thickness of this base layer will vary according to your particular site and project requirements. If you would like more information on how we can help you design your pavement for optimum performance, contact us today!
Yes. Pervious concrete meets ADA requirements for both smoothness and flatness.
Yes! While most pervious in the United States is made with a 3/8” aggregate, CMS Pervious recommends the use of a clean ¼” crushed stone which allows for a smooth surface and less cleaning. Some areas also have a beautiful ¼” aggregate, referred to as a “barefoot finish” that can be used. Integral colors can be easily added to make pervious concrete even more attractive. If you have specific questions about colors, aggregates, or finishes please contact us.
We specialize in providing consultation on stormwater management systems design, pervious concrete specification development, engineering documentation, and on-site infiltration rate testing. Our consulting fees can run per hour, per day, or per project.
Knowledge is power, and we want to empower you to take your stormwater design to the next level. Our presentation will walk you through the history and pros and cons of using pervious concrete, and help you maximize your design and minimize your costs while meeting stormwater regulations, without sacrificing site design. We typically present for 50 minutes and take questions for another 15-20 minutes. Schedule an office presentation here.
No, not at all.
The unique properties that allow water to pass through pervious concrete also make it behave quite differently during transport, installation, and curing. In fact, we do not even use the same tools used in traditional concrete. The ideal method of installation is with two very specialized pieces of equipment called a hydraulic roller screed or a laser-guided screed. No other methods can match the level of compaction, density, and finish.
In terms of mix design, installation technique and timing, the window of tolerance for a successful installation is very narrow. The failure rate for pervious concrete installations by inexperienced and non-certified contractors is over 70%. When it comes to pervious concrete there is no room to guess. If it goes poorly there will be a very unsatisfied client that may insist that the work be torn out and done again.
Due to the specialized nature of pervious concrete it important that your contractor understand the properties of and all installation needs of the product. Test pours prior to an actual job are critical for a crew to understand the steps needed for a successful installation.
Yes, there is a certification, and it is important that you verify the installer is certified to ensure they have the education and training to do the job right. The National Ready Mix Concrete Association (NRMCA) is one of three certifying bodies. NRMCA, CPG, and CMS issue a certificate of qualification to each individual who qualifies. All three groups certify technicians, installers, and craftsmen. CMS also has bolt-on certifications for batchmen and field testing technicians.
Although it technically is concrete, pervious concrete has unique properties that cause it to behave very differently. As such, it requires a completely different set of skills and knowledge that can only be acquired through completion of certification and sufficient hands-on experience with the product.
Please contact us and ask! We are happy to answer your questions.