Polishing Lets Concrete Shine

When Shawn Wardall of Specialized Construction Services, Inc. took on an 11,000-square-foot polished concrete floor at St. Francis of Assisi Catholic Church in Belleville, Wis., he wanted to bring the congregation a beautiful, natural-looking floor to match the unique architecture of the building. He also wanted to introduce a flooring technique to the area that would offer a low maintenance finish, longevity, the ability to customize a floor to the building around it and open doors for concrete polishing. The end result is a floor in a mixture of rich tan and chestnut brown that exceeded the client's expectations thanks to preplanning and contractor expertise.

Planning the floor

Wardall says the key to a great finished project is thinking ahead. He was lucky to be involved with the church floor project in its early planning stages, giving him the chance to work with the client and architect to determine what they really wanted in a floor and the chance to work with the concrete contractor to optimize the performance of the floor for a quality finished project.

When Wardall met with the building's architect and the church's planning commission, he educated them on the benefits of polished concrete flooring over other options such as carpet. He also accompanied them to another church in the area where he had performed the polished concrete floor work, giving them a firsthand look at what a finished concrete floor system looks like, how it performs and its lower maintenance benefits.

An important feature of the floor that Wardall was able to accomplish through preplanning has to do with what it's missing - control joints. "I think there's a real visual benefit to be able to look down an aisle and not see control joints," Wardall says. "I think a random crack lends itself to a natural floor - like aged leather - and the randomness adds beauty. Natural fissures are much less of a distraction than control joints."

Wardall points to color performance as another reason to avoid control joints on a decorative floor. "Because the concrete cures differently around those control joints, dyes and stains look different about an inch around those joints," he explains.

After discussions with the architect and the church's planning commission, the architect removed the spec for the concrete contractor to saw control joints in the floor.

In order to achieve the kind of floor that lends itself best to polishing and to minimize random cracks, Wardall and the concrete contractor devised a plan for a wet cure for the floor. After placing the floor, the concrete contractor covered it with visqueen and everyone stayed off the floor for one week. After a week's time, the visqueen was removed and the floor was covered with Tyvek and plywood for three months; during this three-month period traffic was allowed on the floor. "The floor retained moisture for three months over the course of the summer, creating an optimal curing and hydration process for the concrete," Wardall explains.

By the time Wardall had finished the floor in late October, only minimal random cracking had begun to occur on the floor. Random cracks occurred on the raised altar portion and steps, however, as that area was poured differently, and therefore cured in a different manner.

"Eventually the floor will see some random cracking, but the longer it takes, the smaller those cracks will be," Wardall explains.

Polished to perfection

To achieve the natural look Wardall wanted for the floor, he used four dye colors to tint and highlight the integrally colored concrete. Wardall likes the effect he gets by using dye on a polished floor. "Dye is a fine particle, and I prefer an acetone-based dye. They seem to be better at penetrating a floor and getting a color to stay vibrant and successful throughout the life of the floor," he says.

Aisles and the main portion of the altar are a mottled rich tan, while the areas of the congregation floor under the pews and the edges of the altar steps are a mottled chestnut brown. Wardall separated the color changes with a shallow score line he cut with a 4-inch angle grinder and a steady hand.