Commercial Roofing Specialists in Michigan and Around the World CEI Group has earned a reputation as one of the country's most progressive roofing firms. They pioneered single ply roofs in the 80's, were one of the first roofing companies to maintain their own sheet metal shop, and today, they are leading the way in green roofing projects. As a union-shop, CEI is also known for their trade craftsmanship. Some of the lost art and techniques for working on architecturally-challenging or historical elements have been preserved and passed down from veteran roofing pros. CEI customers appreciate the company's disciplined project management, communication during the project, and ability to consistently meet challenging deadlines. "We take the stress and uncertainty out of your toughest roofing challenges." Eric Cook, Vice President, CEI Group