Membership Directory Construction Companies, General go Results Found: 2 Button group with nested dropdown Dingeman Concrete Inc Dingeman Concrete Inc 1097 Hwy G 46 Knoxville Iowa 50138 (641) 780-6200 Septagon Construction Co., Inc. Septagon Construction Co., Inc. 2950 S.E. Gateway Dr. Grimes IA 50111-5000 (515) 986-7313