Isolate Cracks, Set Tile, Keep Mall Open
Renovating Genessee Valley Center, Flint, MI, involved replacing the existing floor with a new tile floor. A crack-isolation system made work possible at night so the floor could be used by shoppers during the day.
When the management of Genesee Valley Center, Flint, MI, started planning a complete interior renovation, they wanted to make sure that everything-including the floors-contributed to what its marketing slogan describes as a “GeneSEE Experience.” At 1.3 million sq. ft., Genesee Valley Center is the largest regional shopping center north of Detroit. The enclosed center features 130 stores.
The architect of record, JPRA Architects, Farmington Hills, MI, partnered with Communication Arts of Boulder, CO, to design the renovation project with a fresh look in mind. The renovation involved more than 85,000 sq. ft., including all of the concourses and court areas. The existing flooring was replaced by new carpet and ceramic tile. The total tiled area was 46,359 sq. ft.
To achieve a distinctive look in the flooring, the architects fashioned a complex design pattern using tile sizes of 4 x 18, 9 x 18, and 18 x 18 in. The pattern, consisting of alternating bands of tile from manufacturer Ceramic Technics, Alpharetta, GA, in the colors of titanium sand, quartz, giallo, and earth, circulated around the perimeter and throughout the court areas.
Achieving this functional beauty wasn’t without challenges. Crews had to remove existing tile and terrazzo flooring that was more than 30 years old before the new tile could be installed. Then, the underlying concrete was cleaned, patched, and leveled to provide a sound substrate.
Cracks in the substrate-both visible and potential-also had to be addressed before the new tile installation could begin. Shrinkage cracks, which naturally occur as concrete substrates dry over time, can migrate upward and cause new tile to crack. The tile also had to be protected from control joints that builders placed in the concrete substrate to channel random shrinkage cracks.
Additionally, the floor installation had to move quickly. Genesee Valley Center management required all tile flooring work, including demolition, laying new mortar, setting tile, and grouting, to be conducted while the mall was closed, between 9 p.m. and 7 a.m. The work was scheduled so that only small sections of the mall were closed off at any given time. In a business where profits can vanish with the slightest miscalculation, tile contractors are under the gun to get the most efficiency out of materials and labor. Selecting a crack-isolation format was among the important decisions.
Traditional membrane crack-isolation formats require at least two steps-installing the membrane and troweling the mortar-before setting the tile. Some formats require a third primer layer. Membrane crack-isolation systems require 4 to 16 hr. between application and the setting of tile. Then, another wait of at least 12 hr. is needed for the tile to cure before it can be grouted.
“When you use a sheet membrane to isolate cracks, it requires sheeting material and mortar to get it done. The tile setters are having to put down the membrane and then wait to set the tile,” said Larry Noyce, president of Precision Ceramic Tile, Burton, MI.
Considering the available tile-setting options and the rigid time constraint involved, JPRA Architects specified the TEC brand of 1Flex Fast Set crack-isolation mortar from Specialty Construction Brands, Arlington Heights, IL, to set the tile. 1Flex Fast Set is a single-component modified polymer mortar that acts as a tile-setting mortar and a crack-isolation system that protects against cracking to a depth of 1/8 in. It makes it possible to isolate cracks and set tile in a single step. 1Flex Fast Set works by adding a blend of flexible polymers to high-strength cement-as much as 10 times the polymer concentration of standard latex mortars. It contains a blend of spray-dried polymers and hydraulic cement, which allows grout to be applied within 4 hr. of setting tile, much sooner than normal set time.
Each section of the mall’s tile installation was choreographed over the course of two nights. A demolition crew would remove the existing tile, prepare the substrate, and reopen the floor to light foot traffic the next day. The following evening, the installers would isolate cracks and set the tile in one step, then grout. The completed floor section was then opened to shoppers.
Noyce said that 1Flex Fast Set did away with the need for additional crack-isolation materials, such as sheet membranes, mesh, and extra mortar. By isolating cracks and setting tile in a single step, it reduced labor costs. “This advanced setting material made it possible for us to grout without a significant delay. There’s no question that 1 Flex Fast Set played a key role in the success of this project,” he said.
Mall management was impressed by the installation efficiency and appreciative that the project didn’t interrupt traffic. “It was a real assembly line,” said Clyde Cooper, Genesee Valley Center general manager, of the flooring work. “The tile removal people would get a section done and then the tile installer would come in right behind. It was challenging for all, but it worked out.”
Meanwhile, JPRA Architects got the flooring look it envisioned and the assurance that the new tile would be protected from shrinkage and stress cracks in the substrate.