Illinois Valley Insulation proudly serves all of North Central Illinois and the Illinois Valley. From Princeton to Naperville and Rockford to Bloomington including towns of Peru, LaSalle, Spring Valley, Ottawa, Streator, Mendota, Morris, Joliet, Granville, Oglesby, Tonica, Dixon, Sterling, Rock Falls, DeKalb, Sycamore, Rochelle, Henry, Chillicothe, Geneseo and all areas between. The only full time, full service insulation contractor in North Central Illinois and the Illinois Valley.