TR Arnold and Associates, Inc. is an employee-owned company providing services to the Manufactured Shelter/Housing Industry since 1967. TRA's services comprise of engineering approval, drafting, plant layout, DAPIA, IPIA, third party modular plan review and inspection services. We are an approved DAPIA and IPIA under the HUD Manufactured Housing Program. TRA also provides third party plan review and inspections for all types of modular buildings. T. R. Arnold & Associates, Inc. Accredited by: The International Accreditation Service (IAS) ISO 17020 #AA674 and; The Standards Council of Canada (SCC) 17065 #10064