Decorative concrete’s advantages are numerous, but the crucial element for a community college in the CUNY system like Queensborough Community College is versatility and cost-effectiveness.
Our second job at Queensborough Community College in a year, the cafeteria and student lounge project, located in the science building, involved several different procedures before it could be finished. The 17,500 square-foot area (nearly half an acre) is situated on two adjacent levels; our crew not only ground and polished the two main levels, but also designed and poured wheelchair-accessible ramps, four sets of steps and a large open sitting area.
Our biggest concern working in a high-traffic area like a college is safety. We check and double check that students and faculty cannot accidentally walk into a work zone, and all our workers are equipped with hard hats, dust masks, steel-toe boots and eye protection at all times.
Queensborough Community College took care of the floor preparations for us, which included installing a radian heating system tacked in to foam so that, when we finished our part of the project, heat would radiate up through the floor, taking advantage of the concrete’s natural ability to retain warmth. This system will help the college become more ecofriendly. Since we were given an already demoed space, we could work quickly and focus our creative and collaborative energy on the artistic aspects of the pour and polish.
The Cement Pour
Working in a large area required us to pour cement one section at a time, so the crew worked back to front along the lower section first. Pouring revealed a spectrum of lovely incorporated grays and blacks, beautified by the natural light aggregate exposure in the cement.
The Diamond Grinding ProcessAbove and below: mapping Control Joints
Though concrete usually takes up to 30 days to settle, we were able to start the grinding process within two weeks, which proved to be excellent for our project timeline. Part of diamond grinding involves saw cuts in an area as big as this job site, and these control joints were determined by a licensed architect – admirable professionals with whom we’ve worked closely for years, Hill and UBT. Control joints’ primary purpose to to alleviate air pressure build up, but they also help cement lose its moisture from the bottom up, leaving a clean, smooth surface for us when we polish.
After the joints were cut into the concrete to control the amount of moisture and air accessible to the surface, our team filled them with polyurethane, a synthetic resin which protects the joints.
All Polished UpAbove: burnishing the concrete
It wouldn’t be called polished concrete without a series of layers of polish to finish up the job. The natural aggregate that was raised during the pour was brought to the surface, ground down and finally polished to an elegant shine.
Finishing TouchesThe finishing touches: straightening the edges of a riser (L) and removing painter's tape along a structural column (R)
The crew executed the final burnish with a flourish, and voilà! The floor is looking beautiful. All that was left were some minor repairs and fixes to ensure the beauty and integrity of the surface and the continued satisfaction of our newest customer, QCC.