This was a unique project we did for a restaurant in Durant, Oklahoma, for several reasons. It involved embedding glass into the concrete, pre cast concrete, and concrete polishing. Making it all come together was quite a challenge. The business owner was looking for a concrete countertop with lots of personality and something customers would remember, and did we ever deliver. The first step was making templates of the area. It was a large project—over 125 square feet—so taking good measurements was critical. We hauled the templates over to the shop, laid them out on a base, and started building the mold. We divided the countertop into 12 separate pieces because it was so big.
This client wanted red and clear glass chips to be a part of the finish. We sprinkled the glass into the mold during the pour, which was then exposed during the concrete polishing process. It took about two weeks before we could actually polish it. Concrete cures with time. If you try to polish green (soft) concrete, it only creates problems. Polishing actually removes material from the surface of the countertop, which is made up of stone, sand, and cement. What happens is that if the cement itself is too green, you have a soft material (cement) surrounding a hard material (stone), and when the concrete polishing starts, you wear away the cement faster than the stone, which makes it stick out. Not pretty. That's why it's so important to let the cement part of the concrete mix harden before polishing it to create a smooth surface.
After we finished the concrete polishing process, we applied a sealer coat on it and loaded the segments into the truck for the two-hour trip up to Oklahoma. Installation took a little over a day because the segments were large and very heavy. Some exceeded 350 lb., which is at the high end of what we normally like to handle for safety reasons. Normally we try to stick to 200 lb. or less. Once all the segments were in place, we applied a colored caulk to the seams that blended them in nicely and then applied a couple of wax coats to help protect the finish.
In our next project we'll show you what molding concrete can do.