Gannon Roofing Supply » Member Listings All current members are listed alphabetically. You may search the full list or filter the results by clicking on a letter. Go back to directory. Add to Address Book. Gannon Roofing Supply Gannon Roofing Supply Contact: Dan Gannon Work 4825 N. W. 6th Dr. Des Moines IA 50313 USAwork Work Phone: 515-282-4415work Work Email: email@example.comINTERNET Website: http://www.grs-inc.com/ Categories: Roofing Supplier Updated 5 years ago.