Meantime, he and Opus keep building: two spec warehouses — spanning 260,000 sq. ft. and 290,000 sq. ft. — recently broke ground in the in-fill suburb of Cicero, on a former General Electric oven manufacturing site. The asking price there of $5 per sq. ft. net reflects the higher cost of land and environmental clean-up work.

Terwilliger and others are encouraged by the big deals that have been completed along I-80 west of Joliet in recent years. Kellogg Inc. put up a 1.1 million sq. ft. distribution hub in Minooka. Clorox Co. settled in nearby with an 850,000 sq. ft. box and then came Kraft Inc. with 806,000 sq. ft. and BMW with 306,000 sq. ft. that will finish up later this fall.

“We had a great year in 2007 attracting industrial tenants to our area,” boasts Nancy Norton Ammer, CEO of the Grundy Economic Development Council, which includes Minooka. Some analysts predict that the kind of concentrated regional big boxes that have come to Minooka will go out of style as corporations extend supply chains to smaller warehouses spread out geographically, hoping to save on fuel costs for trucks.

Ammer disagrees. “We can offer cheap land and no highway congestion way out here,” she says, noting that Chicago is nearly 50 miles to the northeast. Raw land is available for less than $1 a sq. ft. in Grundy, compared with $3 to $5 to the east in Will County, where traffic is a growing headache. “Trucks can get in and out of warehouses here easily, and they have no highway traffic out here to worry about.”

Others think there may be limits, however. David Bercu, a principal with Colliers Bennett & Kahnweiler, is brokering new spec boxes for Corum Real Estate Group, which will soon deliver a 269,000 sq. ft. building in Bolingbrook, and Duke Realty Corp., which has a new 500,000 sq. ft. box in Aurora.

“As distribution centers over the past decade were consolidated from smaller centers to mega buildings, Chicago benefited,” says Bercu. “But now companies are looking at how expensive it is to run a truck from Chicago to Atlanta. They're deciding maybe they could use a smaller facility part-way, perhaps in Memphis.”

For companies considering sites around Chicago, the economic analyses can get complicated, says Eric Fuglsang, a partner at Chicago law firm Quarles & Brady LLP who advises industrial clients. “The corporation considering a secondary market has to look hard at fuel costs. But many of these secondary cities are also willing to advance incentives to help balance out the fuel costs,” he says.

For the moment, the big deals are still occurring on a spotty basis. Minneapolis-based Ryan Cos. recently sold a 70-acre parcel in its Laraway Crossing Business Park in Joliet off I-80 to Swedish furniture retailer Ikea. The company planned to break ground on a mammoth 1.5 million sq. ft. center last spring, but delayed construction until later next year.

Watching Ikea's delay, deep-pocketed Ryan has grown cautious and is eager to close out its Boldt Park in Romeoville, where 55 acres are left, with a 600,000 sq. ft. spec building. But it's resisted putting shovel to dirt so far.

“The I-55 corridor has more than 2 million sq. ft. in spec space available right now,” notes Tim Hennelly, Ryan's vice president of development. “We don't think the market dictates that we build another spec product now.”

Other companies have been more fearless. Atlanta-based IDI recently completed a 450,000 sq. ft. spec building in Bolingbrook, not far from Boldt Park, and has put up another 51,000 sq. ft. small box in Hanover Park, in DuPage County. The company has put off starting on three other spec projects.