Demand for fresh produce, dairy products, and proteins is on the rise. Projections forecast that warehousing space built for refrigerated coolers will grow at a compound annual growth rate of 15.9% by 2030. These chilled areas store fresh meat, fruits, vegetables, and dairy products — either as ingredients destined for further processing, or as finished goods ready for consumers to enjoy.

For food safety, these environments require temperatures from 32°F to 59°F (0°C to 15°C), a costly proposition. Facility owners, therefore, seek to optimize the cubic density of their temperature-controlled square footage. To create the ideal storage solution, there are several best practices used by rack design engineers when planning pallet rack systems for refrigerated coolers.

Rack Selection Affects Space Efficiency in Refrigerated Coolers

Because the costs associated with maintaining specific temperatures in refrigerated coolers are higher than that of ambient storage areas, maximizing space efficiency is paramount, said Tony Sineni, Director of Sales at Rack Builders Inc. The company is a member of the Rack Manufacturers Institute (RMI).

“A good way to achieve that is by providing a denser type of racking system,” he explained. “That could be a two-deep reach system, a drive-in rack system, or pushback rack. Each option allows for higher storage density.”

Deciding which type is best suited for a given application depends on the type of facility and its operational needs, said Sineni. Some end users — such as food manufacturers or grocery distributors — prioritize density over accessibility.

“Conversely, warehouses operated by third-party logistics (3PL) service providers offer leased space to end users,” he noted. “Because these operations don’t always know what type of inventory they’ll be handling, they need more flexibility. Refrigerated coolers in those facilities typically house selective rack or two-deep reach rack.”

Galvanizing: Protecting Against Corrosion and Rust

Another key consideration when designing racking systems for refrigerated coolers is combating corrosion. Industrial steel pallet racks can rust when exposed to moisture, which is abundant in high-humidity cooler environments.

“Most pallet rack manufacturers apply a painted finish to their beams and uprights. Paint does offer some protection against rust — until it’s chipped,” Sineni observed. “Best practice is to use galvanized rack components. Galvanizing is a coating applied by dipping rack members into a bath of molten zinc and other compounds. This protective layer gives the rack structure more resilience to the challenges posed by moisture and humidity.”

Surprisingly, not all products stored in coolers are created equal when it comes to their interaction with steel. Sineni highlighted the exceptionally corrosive nature of dairy products like milk, which can accelerate corrosion. That makes galvanization a preferred finish for racks used to store yogurt, cottage cheese, sour cream, butter, and other refrigerated dairy items.

“Likewise, galvanized rack is the optimal solution for refrigerated cooler environments that require regular washdowns,” he said. “Any areas that are subject to hygienic requirements need galvanized pallet rack. For example, in meat processing facilities the racking system must withstand repeated exposure to water and cleaning chemicals.”

Rack Accessories and Specialized Components

Both roll formed and structural rack systems can be deployed in refrigerated coolers, said Sineni. However, he noted that associates entering temperature-controlled spaces nearly always do so while navigating pallet loads of product by forklift. They’re also wearing heavy parkas and hats or hoods that can inhibit their peripheral vision. It’s a recipe for an increased risk of impacts, particularly of uprights.

“For that reason, you often see structural rack deployed in refrigerated coolers,” he noted.

Another best practice — regardless of the type of rack used — is to use stronger, heavier aisle-facing columns, reinforcing uprights, or adding protection accessories. These devices can help to reduce or deflect the force of an impact.

Further, for refrigerated coolers outfitted with pushback rack — with wheeled carts dedicated to each pallet — using sealed wheels is a design best practice, added Sineni.

“In an ambient application, standard wheel bearings work fine in pushback rack. But in high moisture environments, a sealed wheel has a rubber gasket inside to help protect it from humidity,” he explained. “That extends the lifespan of the wheel, allowing it to roll smoothly for a longer period of time.”

Regardless of the type of rack installed and the accessories used, racking designed for refrigerated coolers is subject to building code requirements, concluded Sineni.

Discover More Rack Design Best Practices

Looking for more insights into rack designs for temperature-controlled areas? RMI offers several resources and publications, including the recently updated “Considerations for the Planning and Use of Industrial Steel Storage Racks.” Additionally, the members of RMI are available to provide guidance, suggestions, and recommendations. For more information, visit mhi.org/rmi.