As stamped concrete continues to gain popularity, more contractors are getting into stamping. At the same time, many other contractors have quit offering stamped finishes to their customers. Stamping is not profitable for them because they haven’t learned how to correct cosmetic defects in their work.

Let’s face it, seldom does a job go perfectly. Even on the best projects there are always some imperfections. However, a customer who pays a premium for a decorative finish has higher expectations. Many clients simply refuse to pay for what they consider to be shoddy workmanship, which means the job can turn into a total loss for the stamping contractor.

Successful contractors have learned to quickly and confidently resolve issues, and having the ability to do touch-ups is essential to that end. If all stamping contractors learned the basics of repair, their businesses would be far more profitable and their headaches would be greatly diminished.

I recently consulted on a project that clearly illustrates this point. A large, outdoor stamped concrete patio was installed to complement the vintage décor of a new microbrewery/restaurant. The patio was poured during the summer’s hottest temperatures, and very near the time that the business was scheduled to open. I was asked by the distraught GC to look at the work, which the owners felt was unacceptable. Upon visiting the site, I noticed several major problems.

Problems: texture, crusting cracks, discoloration

Although much of the patio had good impression, there were areas that were barely textured or lacked imprints altogether. The slab exhibited crusting cracks and a horribly discolored area along the outside wall of the building. Presumably, strong acid had been used to clean powdered release from this wall and ran down, severely etching the concrete.

Additionally, there were large areas where water pooled on the slab instead of running to the drains, and wide gaps where stamps hadn’t been properly butted together. Sawn crack control joints stopped inches from the wall, leaving an ugly, unfinished appearance.

The concrete contractor was at a loss for what to do, and the GC was under pressure to finish the project before the grand opening. In any case, the establishment wasn’t going to open and no one would be paid until the issue was resolved — not the GC, not the concrete contractor, and not the ready-mix producer for whom I worked.

The GC thought a costly tear out and re-pour was imminent. Having seen many of these issues before, though, I assured him they could be quickly repaired. I called a couple of friends and the next morning we attacked the job.

Solutions: grinding, patching, and coloring

The first orders of business were to continue the saw cuts to the wall, grind in the missing or barely impressed stamp joints, and address the areas where the stamps weren’t properly aligned. We continued the saw joints to the wall using a 4-inch grinder equipped with a thin diamond blade. We then switched to a tuck-pointing blade for working on the wider stamped joints. Grinding in the missing joints not only defined the stamped cobblestones, but also created channels in the slab that allowed water to flow to the drains. While my two co-workers were grinding the joints, I tackled the crusting cracks.