Chicago Developer Wants to Erect Tower With a Twist

A decision about whether the proposed Fordham Spire is built, he said, is "going to be all about the economics."

In a nod to nervousness, a fact sheet distributed by Carley's team promises a "heavily reinforced concrete" core able to withstand high temperatures, and two "independent systems of emergency exits."

Calatrava, describing the design as being based on a sculpture he did early in his career, said he has returned to the idea many times. The Chicago spire would fit in a series of buildings that include projects proposed for New York City; Malmo, Sweden; and Valencia, Spain.

"I find that each new building raises problems that only the next building can solve," said Calatrava, who designed an acclaimed art museum up Lake Michigan in Milwaukee, completed in 2001.

The Fordham building would rise on 2.2 acres at E. North Water Street and Lake Shore Drive, near Lake Michigan. Although so tall, it would have fewer than a million square feet, divided among retail space, a hotel and luxury condominiums. The Sears Tower, built in 1974, contains 4.5 million square feet.

As described in the developer's documents, the twisting effect would be accomplished by building out each floor like a separate box with concave sides. Each box would be rotated slightly farther.

Trump's 92-story tower has no such aspirations. But the cranes and crews are there every day.

"One thing about the Trump tower," said Klemencic, "is it's underway, whereas the Fordham project with Calatrava is still kind of a twinkle in the developer's eye."