ROSEMONT, ILL. — The Naperville, Ill.-office of Ryan Cos. US Inc. and Oak Brook, Ill.-based The Harp Group are breaking ground on Rosemont Corporate Center, a 121,000-square-foot office building located near the corner of Balmoral Avenue and River Road in Rosemont. The Class A, four-story building is being designed to achieve LEED Silver certification. Sustainable features of the building include an under floor air distribution system, energy efficient mechanical and electrical systems, and water conservation plumbing features. San Jose, Calif.-based Cisco Systems has signed on as the building’s lead tenant, occupying 82,000 square feet of space. Cisco System’s space will also be LEED certified.