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recommendations. "Our first look showed a beauti- ful building with lots of special comfort features, and then we saw the floor. Approximately 800 square feet looked like raised corn rows," explains Mark Elijah, BodyTek's sales representative who accompanied Jeff Adney on the job. On the recommendation of "someone," the farmer's employees had used a milling machine as a scarification tool to smooth the floor. Unfortunately, this technique had chewed away the entire surface and left grooves up to 3/8-inch deep. In all, after BodyTek's crew "sounded the floor and removed approximately another 700 square feet of floor surface, a total of 1,500 square feet needed to be filled to an average depth of 3/8-inch to recreate the original concrete floor surface," explains Adney. And, as if that weren't enough, the expansive floor only had one expansion joint running transverse across the floor approximately at the center of the build- ing. The floor had no control joints. "It was interesting. It looked like the installing contractor had simply divided the floor in half," Adney says. "Natural control joints were made in the floor at the weakest tensile areas by the cracks. Over 400 linear feet of cracks had developed. What was unknown was if the cracks were following the radiant heating system." Typically, control joints are purposely installed in concrete floors that are exposed to wide temperature changes to prevent random cracking which will incur high annual maintenance costs. Sealed control joints also help preserve the radiant heating system from unwanted water and chemical exposure. "Ordinarily, we would install control joints (or saw cuts) as part of the rehab, but this was an unusual floor. A plan was not available showing the actual locations of the heating system, nor its depth. This was not a questing game. We were afraid that if we cut through the concrete at the American Concrete Institute (ACI) recommended depth of 25 percent of the slab thickness, we would nick the tubes and possibly destroy the entire heating system. After discussing it with the farmer, we decided to simply clean and chase the existing cracks and original joint, but not to add any other joints or to make any saw cuts," states Adney. Like a Sponge Another identifiable floor problem was the obvious porosity in the floor surface. Salt had been spilled on a portion of the floor and with high summer humidity it had partially dissolved and penetrated into the concrete, causing spalling. And, this had occurred in the area that was damaged when the owner's employees milled the surface. ABOVE The 10,000 sq. ft. floor only had one expansion joint running transverse across it at approximately the center of the building. Additionally, there were no control joints. "It looked like the installing contractor had simply divided the floor in half," Adney says. "Natural control joints were made in the floor at the weakest tensile areas by the cracks. Over 400 linear feet of cracks had developed. What was unknown was if the cracks were following the radiant heating system." four days, from prep to final install. This speed of crew and materials was critical. The farmer needed a fast repair because Salt had been spilled on a portion of the floor and with high summer humidity it had partially dissolved and penetrated into the concrete, causing spalling. Elijah explains, "We knew that any recommended system had to be imperme- able and durable because of the building's use. We also understood that all moisture coming from the top of the concrete surface had to be stopped with the polymer overlay, otherwise the existing salts that had already penetrated would continue to cause corrosion." he needed his building returned to service in time for the harvest. Cleaning Without Destroying the Surface Adney adds, "And along with the durability, the flooring system needed to be attractive because of the employee use, so we chose a self-leveling system from Crown Polymers to not only repair, but also seal the concrete and provide that extra decorative look." In total, the crew would have just Day one of the four day job started early with a surface preparation sub-contractor, M & M Epoxy Supplies, Inc. The owner, Mike Nowicki, who has been clean- ing concrete surfaces for over 12 years, and another cleaning specialist arrived on-site for shot blast prep work. Donning goggles, ear protection, and dust masks, they prepared to shotblast the floor. To remove the failed concrete, surface contaminates, and laitance on the floor, the crew used a Blastrac 1-15D Super January 2009 J www.coatingspromag.com 81