Don Mischo recalls driving his boss and longtime friend, Ken Hendricks, to the airport nine years ago. Hendricks, founder of building materials company ABC Supply, paused before boarding a plane to Europe and charged Mischo with a task. "I want you to check up on Larry," said Hendricks, referring to an ABC maintenance man who had become seriously ill and gone to live with his mother in Tennessee. "Make sure he's getting the best doctors. And if he wants to move back here for treatment or anything else--make it happen. Charter a plane for him if you have to."

Hendricks, who died on December 21, at age 66, helped a lot of Larrys in his long career. That he was killed in a fall from a roof under construction at his home is testament to his undiminished affinity for labor and the building trades from which he made his fortune.

Hendricks's business partner of more than 30 years, his wife, Diane Hendricks, inherited 100 percent of the company. Five of his seven children work for ABC or one of its subsidiaries.

After dropping out of school in 11th grade, Hendricks worked several jobs before launching his own roofing company and starting to buy residential real estate. In 1982, he founded American Builders and Contractors Supply, in Beloit, Wisconsin. The company, which sells roofing, siding, and window materials, hit No. 1 on the Inc. 500 in 1986. By 2004, Hendricks was elevated--much to his amusement--to Forbes's list of the 400 richest Americans. Still private, the company reached $3 billion in sales in 2007.

Despite his wealth, Hendricks preferred spending time with the warehouse guys, the truckers, the roofers--people who understood business and life in ways the suits couldn't. A strong work ethic outclassed the weightiest résumé in Hendricks's eyes. "He would bring people in to interview that had no particular experience but in whom he sensed a drive, a willingness to do the job properly," recalls Jerry Juszak, general manager of Amcraft, another business in Hendricks's empire.

If he loved the common man, Hendricks loathed waste and dedicated his life to recycling and rehabilitation in all their forms. He resuscitated decaying buildings, directly through the millions of square feet he personally owned and indirectly through the hundreds of millions of square feet restored by his customers. On a grander scale, he helped revitalize Beloit by launching or acquiring dozens of businesses and planting them there. He lured others with low rents and custom renovations on his own local properties. (For that work, Inc. named him Entrepreneur of the Year in 2006.)

In the 18 months before his death, Hendricks had turned his eye to energy. He was working on a solar power project, and he had recently acquired (and moved to Iowa) a Danish company that makes wind-farm equipment.

"We're only left to wonder what he might have accomplished had he lived another 20 or 30 years," says David Luck, who as president and COO of ABC has been running the company for 10 years.

It is a sentiment Hendricks would certainly have shared: the tragedy of waste.