William Millen established Millen Roofing in 1893. He and his father, Ignatius, were experienced slate and tile roofers from a roofing family in Alsace-Lorraine. They roofed many churches and fine homes in Milwaukee. William's son, Mathias N. Millen, continued the family craft and business.

Mathias's sons, John J. Millen and Matt M. Millen along with Roger Hamm carry on the tradition of fine steep roofing. Their expertise in the craft, dedication to the finest workmanship, and use of the highest quality materials engenders complete confidence in Millen Roofing Company.