Construction on Kum & Go’s new headquarters in downtown Des Moines was halted Monday because of a labor dispute, according to the Des Moines Register. Ryan Cos., contractor for the building under construction, said work should resume today or Thursday. The Sheet Metal Workers Local 45 union members walked off at their jobs Monday as part of a labor dispute, said the Register. Members have been working without a contract since May 31 when the union’s previous three-year contract expired. Local 45 is negotiating with the Sheet Metal Contractors of Iowa Inc., which represents about 13 sheet metal contractors.