- Unqualified concrete installers,
who probably do not have the right equipment or understand Pervious placement requirements. Because of the great interest created by EPA’s Best Management Practices and Green Building organizations many concrete contractors are taking crash courses and jumping into installing pervious concrete. But you can’t learn Pervious installation from a textbook or short course. We have more than 25 years experience with Pervious Concrete. We do our Pervious installations within our family run company. We don’t subcontract it. And we provide a 10 year warranty.
- Uncorrected soil conditions.
Be sure that base preparation is certified as being up to engineered specification. All organic materials must have been removed from soil under base. Proper drainage must be established if Pervious Concrete is to function as designed.
- Undetected bad concrete mixes.
Experience is the best teacher. We almost always can spot bad mixes immediately and reject them. Experienced Pervious Concrete contractors can tell by the sound of the concrete spinning in the truck or the appearance and feel of the concrete as it comes down the chute, if the mix is not up to quality standards. Sometimes, truck drivers add water too soon while in transit. The resulting hot mix needs to be rejected.
- Lack of the use of qualified engineering.
Don’t rely on firms that do not have successful experience with Pervious Concrete. If the base soil is not properly tested and evaluated, and if the Pervious Concrete Base is not properly designed for drainage and stability, the system will not perform as intended. This is the primary responsibility of the Site Engineer and the General Contractor. The base should be certified by the Site Engineer before the Pervious Concrete is placed.
- Unqualified Test Laboratories.
If the lab does not have years of experience with Pervious Concrete you are playing Russian roulette. Most inexperienced labs try to use test methods that do not address the unique characteristics of Pervious Concrete. And they must be aware of new testing techniques that are being developed in the industry.
To see details about our installation please reference our specification.