Mark Jackson is a 3rd generation roofing contractor and has been employed at Greenberg Roofing for over 30 years. He began performing administration duties for the company in 1974 while attending the University of ND. Mr. Jackson advanced to Estimator, Purchasing and Project Manager. He became president in 1982. Mr. Jackson attended NDSU from 1970-1973 and graduated with a BA degree in Business
Management from UND in 1975. Mr. Jackson has served on the National Roofing Contractors Association Board of Directors (NRCA) and was a member of the Executive Committee and a Vice-President. He has also served on the ND Associated General Contractors Board as well as a number of civic and not-for-profit boards.
Dwight Hofland, Controller
Dwight Hofland graduated with a bachelor of science in accounting from University of Mary, Bismarck. Dwight oversees all accounting and financing for Greenberg Roofing. Prior to joining Greenberg Roofing, Dwight was a General Manager for a construction and development company and a controller for a commercial roofing company in Fargo, North Dakota.
Nathan Roberts, Human Resource and Safety Manager
Nathan Roberts graduated with a BS in Human Resource Management from Valley City
State University. Nathan received his SPHR certification through the Human Resource
Certification Institute in 2007 and has over 10 years of Human Resource experience
in the telecommunication and manufacturing industries. Most recently Nathan was
Human Resource Manager for the J.M. Smucker Company in West Fargo, ND. His
responsibilities at GRS include workforce and organizational development, and safety.
Wendy Wetzel, Accountant
Wendy Wetzel graduated from Aakers Business College in 1982, and continued her studies in the accounting field. Ms. Wetzel joined GR in 1994 and manages the accounting department as well as duties with employee benefits and IT.
Kim Stormo, Accounting
Kim Stormo graduated from Northwest Technical College in 1987 with a Secretarial Degree. Ms. Stormo joined Greenberg in 1989 as the bookkeeper and over the years has been involved in all aspects of the accounting department. She currently performs cost accounting and accounts receivable.
Kalie Shawstad, Contract Administrator
Kalie Shawstad graduated from Northwest Technical College in 1997. Ms. Shawstad is the Contract Administrator, Assistant to GM, and also performs administrative duties relating HR issues. Kalie was with MA Mortenson as an Administrative Assistant prior to joining Greenberg in 2000.
Andrea Rust, Administrative Assistant
Andrea Rust joined Greenberg in May 2005. Ms. Rust is responsible for administrative functions supporting our operations and marketing departments. Prior to joining GRS she worked in the medical field as a Nurses Aid.
Lisa Hale , Accounting
Lisa Hale joined the accounting department of Greenberg in October 2006. She performs duties in the areas of payroll, accounts payable, and accounts receivable. Ms. Hale graduated from Mount Vernon Nazarene College in 1989, and her previous experience includes eight years in the accounting department of a bridge construction company in Ohio.
Julie Sizenbach
Julie Sizenbach graduated from Minnesota State University Moorhead cum laude with a BS degree in Paralegal studies. After graduating, Mrs. Sizenbach worked in a law firm with a criminal defense attorney before joining Greenberg Roofing in 2008. Ms. Sizenbach supports the Fargo office by performing a variety of administrative functions.
