CHICAGO—In the initial phase of the economic recovery, investors began snapping up much of the available class A industrial product. But as the economy has strengthened even further in 2012 and 2013, investors have starting looking, and buying, the smaller and older class B buildings, many in the suburbs, which form the backbone of the Chicago area's industry.

“Two years ago, they weren't even thinking about the B market,” says John Coleman, executive managing principal of Newmark Knight Frank Epic in suburban Rosemont. But several years of growth and strong balance sheets for companies using this building class soothed whatever anxieties investors harbored. Starting around the third quarter of last year, investors “became much more comfortable with the returns and the risk underwriting.”

“And in the first and second quarter [of 2013] we certainly saw an increase in measurable activity.” Since January 1, Coleman's firm has helped complete 21 deals, both leases and sales, in the Chicago area among industrial buildings with between 30,000-square-feet and 90,000-square-feet. “That's something that is pretty positive.” Second quarter transactions handled by NKFE include KTR Property Trust's purchase of a 74,410-square-foot building at 280-290 Gerzevske Lane in suburban Carol Stream, and the purchase of an 81,048-square-foot building at 490 Bonnie in Elk Grove Village by SFP Group, LP.