Since its founding, the business became the largest roofing distributor in the U.S.
But, when her husband died in 2007, Diane directed the company on her own, overseeing a number of important acquisitions.
This included the purchase of L&W Supply for $670 million — which grew the company from a $3 billion business to a $9 billion one.
Hendricks has used her earnings in many ways: providing economic support for Beloit, producing Hollywood movies, and donating more than $1 million to Republican causes.
How it all started
Not long after she met Ken Hendricks, a roofing contractor, the two got into business together.
Over the course of three years, they purchased 100 homes in Beloit, doing them up themselves.
A few years later, the couple opened their first ABC Supply store in Beloit .
The business grew from there and in 2001 the couple formed Hendricks Holding Company, which now holds a portfolio that includes industrial companies, logistic companies, real estate, health care and more.
How she managed after the passing of her husband
Diane's husband sadly passed away in 2007 where he fell through the roof of his home in Wisconsin. He was 66.
She told the New York Times in an interview
"I knew the businesses had to go on. It was our life’s work, I worked out of my home for the first year after his death, and senior employees came there to conduct business."
Diane explained that her main focuses were "being more selective about" acquisitions and doing "capital repairs instead of capital replacements."