Contemporary, Practical, and Cutting-Edge
Polished Concrete Floors Reflect Corporate Culture
Polished concrete flooring may be known for its light reflective properties, but at the new offices of a prominent Austin, TX, technology company, the application is enhancing more than the building’s interior illumination. “The floors reflect the company’s corporate culture of design,” says Wendy Rosamond, interior designer for STG Architects, the Austin-based firm chosen to execute the new construction project. The company, an international designer and manufacturer of personal technology devices, is known for out-of-the-box thinking and industry innovation. Created around those trademark qualities, the practical and contemporary office emulates the same ideals the company strives to achieve with their product line. “We wanted to create the culture of the client in the space [which is] innovation, ingenuity and creativity,” explains Rosamond, “for the flooring, I was looking for a practical yet finished design that was both contemporary and practical.” She found her solution in polished concrete, which she used to, “add to the overall look and flow of the space with a variety of subtle design… [and] handle the heavy foot traffic of the 24-hour facility.”
Designed to unify the nearly 6,000 sq. ft. space, the polished concrete floor mimics the dropped ceiling element above the main lobby. “It was a challenge to create a cohesive design in such a large area,” Rosamond says, “but with polished concrete we were able to use a variety of colors and exposures to cross an arc with a linear pattern.” A radius style with multiple seams, slabs and color patterns, the floor is, “unique because it is essentially four different floors…the slabs use two different colors with two different aggregate exposures for a total of four combinations,” Rosamond says. By using dual shades of integral color, light gray and dark gray, along with large and small aggregate variation, the floors give a continuous design between the building’s two main entrances while also meeting the practical performance standards required for such a heavily-used space.
The sophistication of the design presented its own set of challenges for American Concrete Technologies (ACT), the Houston-based contractor selected to polish the office floors. “Each type of slab was essentially a different floor on one continuous level” explains Jeff Parker, ACT South Texas Branch Manager and project leader, each having unique requirements for pour and polish steps. The pourer did a good job” he says, “but even with a really great pour there is no guarantee the aggregates will be even…it is a wide-open lobby and any uneven edges definitely show up.” In addition to leveling, the floor mixed high and low exposure with light and dark color and also contained multiple curved expansion joints. “This was a highly specialized process, requiring total attention to detail,” says Wendy Rosamond. With a wealth of experience, the ACT team was up to the task. “We’ve been around long enough to see most of the things that can go wrong on a job like this.” says Tim Taylor, ACT president.
With his company’s solid history of concrete work and specialization in polishing, Taylor is an innovator in his own right. “When we [ACT] started polishing there was only one other contractor in the state of Texas doing it…at first we had to really educate the architects,” he says, “but now it’s really catching on.” His company has grown and now covers four states: Texas, New Mexico, Oklahoma and Louisiana and they are, as Parker says, “excited because polished concrete is taking off”.
Jeff Parker and his four-man team tackled the project over a sixteen-day period, using two polishing machines, two hand grinders and the knowledge that only comes from experience. “Every time you do a job, it’s like adding a tool to your toolbox of knowledge. On this job we basically had to pull out all our tools to figure it out.” He notes that a contractor who had been polishing for a short time would, “not have had a shot at finishing the job”. Technical process challenges included joints that were uneven and places where the full exposure aggregate was poured higher. “We had to hand grind a lot of areas around joints and lower walls,” he adds. “The flatness has to be acceptable; that’s the biggest challenge, just getting it even.” He advises using a hand grinder to prevent chunking and concentrating on getting the expansion joints flush.
In an effort to attempt an even pour, high exposure areas were poured three inches lower than the desired level and the team literally built a bridge over the slabs to sprinkle high exposure aggregate evenly into the mix. Despite this attention, some areas still turned out higher, requiring two methods of grinding determined by desired exposure. On areas of the slab tagged for low exposure, the team had to spend more time smoothing than grinding. “Normally, you’d mostly grind down low then smooth... the low exposure was difficult, we had to quickly change to medium grit multiple times because we didn’t want to go too far,” explains Jeff. For the large aggregate, they, “started with a very aggressive 40 grit diamond and ran it until there was rock visible everywhere - what we call 100% exposure”. They followed with an 80 metal grit and 150 metal grit, then added a densifier before completing the polish up to a 3000 resin grit shine.
“We polished all the way up to a 3000-level shine,” says Parker. “It was all done in 3000,” he adds, “For the record, there is a huge difference between 800 and 3000. Sam’s Club is your typical 800. When you take it to a 3000, you can read the ingredients off a cheerios box off the floor.” He often refers to a topical coating as a “fake finish” because he feels the client is getting “cheated out of stages” of the polishing process. With a topical treatment, Parker notes that the look will be flatter and later a maintenance nightmare. He is also quick to point out that though his team sometimes uses a topcoat, it is a permeable coating that goes into the floor as opposed to simply hardening on the top.
“Maintenance was a huge factor in the decision [to use polished concrete.]” Wendy Rosamond says. “Stained concrete in a color-to-color scoring pattern could give the same look, but polished concrete was set apart by its ease of maintenance.” As a 24-hour facility with constant traffic, it would be impossible to shut down totally for floor renovation and very inconvenient to close off parts of it. Also, any resurfacing would have to take place while workers are in the building. Since polished concrete requires minimal daily cleaning and will hold polish for years without adding anything to it, the application was a perfect choice. Two other benefits, low cost and sustainability, added to the attraction. Tim Taylor tells potential clients to consider the lifetime cost in addition to the upfront price: “Over a twenty year period, the only thing cheaper than polishing is not doing anything to it at all.” Wendy Rosamond notes that though the office was not going for LEED certification, the clients were still concerned about the carbon footprint of the project. “The clients were very conscious of green energy savings…less product and man hours ultimately mean savings in every area.”
“The client was very please. One of the Vice-Presidents visited and really liked the design.” says Rosamond, adding that the general response was overwhelmingly positive. Taylor Parker of ACT agrees. “People are shocked at how beautiful it looks and they almost don’t believe it.” Durable, attractive, low-maintenance and reflective of the company’s cutting-edge ideals, polished concrete cultivates creativity in design. As Wendy Rosamond put it: “Polished concrete is a great compliment to the overall design; it really helped create the culture of the client.”