Bernie Cawley, the director of marketing and administration for the Michigan Concrete Association, Lansing, Mich., says that about 80% of their complaint calls used to be problems related to plain concrete flat-work. But about three years ago that shifted to 90% of complaints being about decorative concrete. “Some of the calls from owners pointed to thoughtless mistakes on the part of contractors,” he says. “For instance, one homeowner called to complain about a worker walking across a freshly finished colored patio with no attempt to remove his footprints afterwards. Another owner complained about a color-hardened garage floor slab that had no color near the wall farthest from where workers were throwing color. But other problems were more technical, such as how to deal with the effects of efflorescence on colored concrete.” The range of complaints included issues with exposed aggregate finishes, chemically stained concrete, stamped concrete, and other decorative finishes. Specific problems included scaling finishes, hard-stamped and soft-stamped patterning, improper joint layout (and good joint layout without pre-job education for owners), and expansion issues around pool decks.
The Michigan Concrete Association decided it had to act, so it developed a decorative concrete certification training program for finishers. The program is now in its third year. Currently of 350 people who trained, 100 have completed the certification process. The prerequisite for decorative concrete certification is successful certification by the American Concrete Institute (ACI) as a flatwork finisher.
ACI and the American Society of Concrete Contractor's (ASCC) Decorative Concrete Council (DCC) are currently in the process of developing a certification program for decorative concrete, partly modeled on the Michigan Concrete Association program. According to John Nehasil, ACI's Director of Certification, a survey is being circulated to find out more about industry acceptance for the program and about how many would want to become certified.
Progress toward certification
Cawley foresees the day when project owners will require that finishers be certified before working on their jobsites. Companies like Wal-Mart already require ACI flatwork finisher certification for floor construction projects. The goal is for crews to possess a knowledge base and know what to do when problems arise. A higher quality of work and better durability would result.
Lance Boyer, owner of Trademark Concrete Systems, Anaheim, Calif., is the committee chairman for the DCC. He and a task force are helping to develop the program for ACI. He says that the program's aim is to certify individuals, not companies. “Individuals occasionally change their employment, so it doesn't make sense to certify a company,” he says. “The object is to have knowledgeable crews doing the work, something a good construction company would also want.”
The DCC's goals for certification include:
- Increase the quality of installed work.
- Reduce the amount of poor workmanship.
- Focus initially on place-and-finish decorative concrete treatments such as exposed aggregate, integrally colored and color hardened finishes, and stamped concrete patterning.
Like Crawley, Boyer also hopes that a decorative certification program will encourage project specifications to require certified personnel, or at least certified crew leadership. He adds that by the time of the March ACI convention in Charlotte, N.C., the proposal will be well defined.
Not all decorative concrete work involves placing and finishing concrete however. In fact much of it is what Boyer refers to as topical. This includes chemical- and water-based staining, paints and coatings, colored and decorative sealers, dye coloring, stencils, diamond polishing, engraving, and overlay concrete treatments. There are no plans presently to include any topical decorative treatments in the certification process. Many contractors who do this work have no experience at all placing and finishing concrete and possess little understanding of concrete basics or the changing chemistry of the material. Should there be a certification process for them too? Probably. For contractors it's frequently not what they know that gets them in trouble, it's what they don't know—one can never know enough about this complicated material.