From the July 2006 issue of Entrepreneur

Competition placed some limits on Kelly Luckett and Mike Crowell's architectural sheet metal business, but they dreamed big. In 2001, four years after founding Florissant, Missouri-based Saint Louis Metalworks Co., they decided green roofing was the future.

Covering a roof with plants is environmentally friendly, but has traditionally been expensive and difficult to do. So the pair created Green Roof Blocks--aluminum trays containing soil and plants. Compartmentalized and mobile for easy installation, the blocks are designed to last 65 years with no maintenance, since the plants resist drought and require no irrigation. Better yet, the blocks increase roof life up to 200 percent and lower heating and cooling costs.

Luckett and Crowell, both 43, now have customers nationwide and an office in China. Says Luckett, who estimates 2006 sales of Green Roof Blocks to exceed $1 million, "You calculate to minimize your risk, but at some point you have to jump off that cliff."