Scott G. Winterton, Deseret News
Okland Construction workers begin placing steel sections for the 22-story 222 South Main Street tower, which will change the skyline of downtown Salt Lake.

The concrete foundation is set, and work on the steel frame of the first office tower built in downtown Salt Lake City in a decade has begun.

The first steel girders that will support the 222 South Main building were put in place Monday. Chicago area-based Hamilton Partners is constructing the 22-story office building that is scheduled for completion in 2009. The 316-foot-tall structure will be one of Salt Lake's tallest buildings.

The tower's listing agent, CB Richard Ellis, has already begun lining up tenants, which will include law firms and accountants, as well as banking and financial-industry professionals.

The tower will be the first building designed in Utah by the architecture firm Skidmore, Owings and Merrill. The firm has designed such skyscrapers as the John Hancock Center and the Sears Tower in Chicago.

"It's going to be architecturally one of the most unique buildings in downtown we've ever seen," said Scott Wilmarth, senior vice president for office properties for CB Richard Ellis.

Project manager Fred Strasser of Okland Construction said the foundation took two days to pour, using 5,600 cubic yards of concrete — or about 600 to 700 truckloads of cement. Getting to the point of constructing the steel "bones" of the building was an important step.

"It's a milestone date for us," Strasser said. "Frankly, just getting the excavation to the bottom of the hole is a milestone for us."

Steel framing, or the "structural steel" portion of the project, will take about eight months to complete. "By the end of the year or first of January, we'll be all the way to the top of the building," he said.

In addition to its 22 stories above ground, the building will have two underground floors, which will be used primarily for parking, as well as some storage areas and service-utilities space, Strasser said.

As the steel frame progresses, probably five or six weeks from now, workers will begin pouring the concrete for the deck or floors on each story. Strasser said they would pour a floor per week for 22 to 23 weeks to get to the top of the building.

To comply with government safety regulations, the crews can never have more than an eight-floor separation between the steel framing and the concrete pouring. Strasser said the hardened cement is needed to provide adequate support for the heavy steel.

"You have to build that diaphragm on the floor to make the steel rigid," Strasser said. The foundation depth ranges from 3 to 5 feet in most areas, and 12 to 14 feet in the elevator pits.

After the steel is erected on each floor, Strasser said, crews would take about four more weeks per floor to build out the interior of the structure, which would include electrical wiring and plumbing.

"We'll be exposed until a year from now to some degree," he said.

At the beginning of next year, workers will begin putting precast glass on the backside of the building, and in the early fall of 2009, they will start to put the glass on the Main Street side, Strasser said.

"The Main Street side is a glass curtain wall, while the back of the house or west elevation is precast with some ribbon windows," he said. "The Main Street side will be a very aesthetically pleasing facade."

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