Hendricks, born and raised in Janesville, Wisconsin, was a high school dropout who joined his father in the roofing business, reshingling houses on weekends. He eventually started his own firm, which grew into a 500-man multi-state operation by 1971, a time when most roofers were still local. After giving the company to the employees so he would have more personal time, he started ABC Supply in 1982 with Diane Hendricks by purchasing three failing Bird and Sons locations. Through the years ABC Supply expanded to almost 500 stores through new start-ups and acquisitions. In 2006, with his personal wealth estimated at $2.6 billion, Hendricks was added to the Forbes list ofthe world's billionaires. He also owned the Beloit Plaza mall and the former Beloit Corporation manufacturing complex, much of which has been completely redeveloped; ABC Supply took over most of the disused Fairbanks-Morse complex, as well. In 2008, he was posthumously awarded, with his widow Diane, a special "20 Year Award of Excellence" from the Downtown Beloit Association because they "nurtured a small movement" that re-energized the city business district. In 2001, he was cited for exceeding the state's campaign laws mandating a $10,000 limit on political contributions. No legal action was taken. Ken and his wife Diane owned and ran several other companies through the Hendricks Group. He was known for his interest in green building technology, and was set to build an environmentally friendly roof for a complex at the 2008 Summer Olympics in Beijing. Hendricks was involved in efforts to build a new stadium for the Beloit Snappersminor-league baseball team, and was the developer of a residential plot in Janesville. In 2006, Inc. named Hendricks its 2006 Entrepreneur of the Year award and he was featured on the magazine's cover. Inc. had ranked ABC Supply its No. 1 Inc. 500 business in 1986, after which it was too large to list.
Death
Hendricks died at age 66 on December 21, 2007, in Afton, Wisconsin, when he fell through a sub floor under construction and into the garage of his home. He left behind his wife, Diane Hendricks, and seven children, Kendra, Kim, Kathy, Kevin, Brent, Kara, and Konya.
