There’s a rule of thumb carriers of temperature-controlled freight try to abide by: for every hour your reefer runs, budget a buck for maintenance. Fuel? That’s another dollar and
a half, depending on the cost of diesel. Two-fifty an hour to run the reefer… It’s enough to give you the chills.

These costs are nothing like the sting of arriving at a customer’s store with a load of spoiled yogurt, says Francois St-Onge.

“Reliability is everything,” explains St-Onge, director of purchasing for Ultima Foods, which produces Yoplait dairy products in Canada. “When it comes to trucks, they should be almost transparent to us: always working, never too costly.”

From its main facility near Montreal, the company uses common carriers for long hauls. But when it comes to delivering to stores and distributors in Toronto, Montreal, Ottawa, and Quebec City, Ultima operates a fleet of 33 straight trucks. The vehicles–Peterbilt 330s from PacLease, the leasing arm of Peterbilt’s corporate parent Paccar–work no more than 150 miles from home, averaging 15 stops a day. The 28-foot and 30-foot insulated van bodies are kept cool by Thermo King reefers.

It’s standard peddle-run fare for a food hauler. Except that St-Onge says he’s saving $30,000 a year with this fleet compared to what he was running before.
The secret, he reveals, is in the box.

The trucks use reefer bodies made of dense polystyrene sandwiched between a sheet of aluminum for the exterior wall and a layer of galvanized steel on the inside, which is painted white and then coated with PVC. The standard thickness is 82 mm (roughly 3-1/4 inches), although 62 mm and 42 mm are available for walls and 122 mm for ceilings. The material comes in panels that are about four feet wide and floor-to-ceiling in height.

The body manufacturer, Laberge Truck Bodies of Maplegrove, Que., glues the panels together–there are no side or roof posts or crossmembers. The process eliminates thermal bridges where warm air can be drawn in and moisture can accumulate. There’s also a significant weight savings: “On a 26-foot body, we typically save about 2,000 pounds in tare weight over your traditional sheet-and-post body construction,” explains Laberge president Bernard Laberge.

The floor is fully self-supporting, so there’s no need for crossmembers there, either. It’s made of panels of birch plywood with a thick layer of fibreglass, resin, and aluminum oxide. The exterior face is pre-painted galvanized steel, and the floor insulation is the same type of high-density extruded polystyrene used on the side walls and ceiling.

Laberge markets the insulated van bodies under the “Isomodule” brand, and credits the sandwich design to a French company that has a 35-year track record with it. Bernard Laberge says the panel construction is ideal for bodies from 16 to 30 feet and can accommodate “all the options you’d want–tie bars, kick plates, etc.” He notes that because the polystyrene is waterproof, its insulation value remains constant over the years as opposed to urethane-based insulation, which can absorb water and break down. Also, he says, the metal skins of the body protect the insulation from moisture better than fibreglass.
The insulation means the reefer doesn’t have to work as hard to maintain a set temperature, Laberge says. “Yoplait was running its reefers for anywhere from 1,500 to 2,000 hours per year. Cut that amount in half, which is what we’ve done, and they’re saving 1,000 hours. At a buck an hour times 33 trucks, there’s your $30,000 a year, not counting fuel.”

For St-Onge, so far it’s been a tasty experience.Ultima’s 33-truck fleet–Peterbilt 330s on full-service lease contracts from PacLease-is comprised of 16 28-foot bodies and 17 30-foot bodies that use Laberge’s foam-sandwich insulated panels. Each has a 94-inch interior height, 97-inch interior width (102-inch exterior), and Whiting Coldsaver insulated roll-up doors. The interior width was achieved by using 62-mm-thick side panels; the front wall, ceiling, and floor all have 82-mm insulation. The walls are smooth inside: there are no posts–and no thermal bridges to transmit the exterior temperature toward the interior.