Ken Hendricks, a roofing mogul who became one of nation's richest entrepreneurs, died on Friday after falling through a garage roof at his home in Rock, Wisc., according to his company, ABC Supply Co. He was 66.

Hendricks, who was named Inc. magazine's entrepreneur of the year in 2006, was overseeing construction on the roof Thursday night when he fell. He died of massive head injuries in surgery the following morning, the company said.

"This is an enormous tragedy and a great loss to the family, associates, and the community," the ABC Supply statement said. "Right now, we are focused on working through the initial impact of this tragedy with primary focus on the Hendricks family."

A high school dropout, Hendricks learned the roofing trade from his father and eventually founded a wholesale roofing distributing business that turned over $3 billion in business a year with 6,000 employees and 390 locations.

"Whatever you do, do the best you can and never set a limit on how far you can go," Hendricks told Inc. magazine last December. "It doesn't matter what you do. It's always fun if you're successful."

Hendricks is survived by his wife and seven children.