Packing heat: Firehouse Subs reels in franchisees with low start-up costs, high volumes and classic hot sandwiches.(Growth Strategy)

Brothers Robin and Chris Sorensen are used to taking risks. As firefighters for the Jacksonville Fire Department in Florida, they had regularly put their lives on the line.

So many close to them weren't surprised when the former firefighters took another risk in 1994. Pooling about $30,000 from family and friends and using a credit card from Robin's mother-in-law, the brothers launched Firehouse Subs, a fast-casual concept that serves steamed submarine sandwiches.

The gamble appears to be paying off. Firehouse Subs is burning through the Southeast. With 148 units in nine states, the Jacksonville, Fla.-based company is getting closer to its goal of becoming one of the top five sub chains by 2008, banking on its franchising system to grow the chain.

Hot from the Steamer

Firehouse Subs says it differentiates itself in the crowded sandwich segment by serving steamed subs with fresh, high-quality ingredients. Every day unit workers slice cheeses and fresh meats instead of using frozen cold cuts. The meats and cheeses are steamed and placed on a toasted roll.

Best sellers include the Hook & Ladder Sub, $4.59 for medium and $6.19 for a large half-pounder, smoked turkey breast, Virginia honey ham, melted Monterey Jack cheese, mayonnaise, mustard, lettuce, tomato, onion and a kosher dill pickle; and the Firehouse Steak Sub, $4.79 for medium and $6.59 for a large half-pounder, slices of sauteed sirloin steak, onions and bell peppers, smothered with melted provolone. Food costs range from 33 percent to 35 percent.

The 1,500-square-foot units sport a fire-station theme that includes spotted tables similar to a Dalmatian's spots, red and white walls accented with black chair rails, exposed brick columns and red quarry floor tiles. Fire trucks and hats, fire-station signs, and black-and-white photos of fire-fighters round out the decor. …