Floor Insulation Holds Its Own Under Pressure

For more than a century, Hershey Creamery Company (not affiliated with Hershey Foods Corp.) has been making Ice Cream in Harrisburg, PA. As the company grew, it faced limited expansion room on existing property. To keep up with growth, Hershey broke ground on a 19,000-sq.-ft. cold storage/distribution facility, its Middletown Distribution Center (DC), with storage capacity of 1.8 million gallons of ice cream products.

The single-floor facility stands 70 ft. high and features an automatic storage and retrieval system (AS/RS). Two 18,000-lb. cranes, running on rails imbedded into the concrete slab floor, receive, store and retrieve finished product. The cranes move continuously 16 hours a day over the entire 76-ft. by 250-ft. building.

Food Engineering, Inc., a consulting/engineering firm specializing in food and dairy, designed the DC. Because of the harsh environment, proper flooring systems were a critical concern in three areas:

• Moisture absorption: Because the facility operates at -20¿ F, moisture and water vapor penetration were primary concerns. Both penetrate then condense and form ice, which seriously impact thermal performance and temperature control in the facility, thereby threatening product quality.
• Compressive strength: Floors sustaining heavy weight, mechanical abuse or vehicular traffic require superior compressive strength performance and can not be susceptible to deformation or creep. Floor loading in the Middletown DC exceeds 1,400 lb. per sq. ft.
• Dimensional stability: Floor materials with poor dimensional stability can result in swelling, expansion, shrinkage, warping or other distortions. The AS/RS is accurate to within 1/16-inch. Because of the cranes and the heavy racking system, the floor needed to be "super flat," with absolutely no creep.

"It's a heavy system, and very demanding on the floor," said Allan Gailbraith, Hershey Creamery project manager. "We evaluated numerous insulation products. Only Foamglas insulation met all of our concerns."

Foamglas cellular glass insulation is an all-glass, totally closed-cell material that will not absorb water in liquid or vapor forms. Its low expansion/ contraction coefficient, minimizes stress on the flooring system and maintains stability and compressive strength under a variety of temperature, humidity and load conditions. Together, these performance characteristics permit simpler design for load-bearing systems and contribute to system safety and performance.

Pittsburgh Corning Corp., 800 Presque Isle Dr., Pittsburgh, PA 15239. Tel.: (724) 327-6100

Food Engineering Inc., 2507 Old Gettysburg Rd., Camp Hill, PA 17011. Tel.: (717) 761-3731