Warehouse Racking and Pallet Rack Systems: Different Types and Designs

Industrial Warehouse Shelving

The modern warehouse needs to store products for efficient identification, retrieval, distribution, and order fulfillment. When horizontal space is limited, and expansion isn’t viable, it’s necessary to extend vertically or increase density, so what are your racking and pallet rack systems options?

Initial Considerations

When determining the best kind of racking system for your warehouse, there are several factors you need to consider, including:

  • What kind of inventory you’ll be storing and retrieving, including the height, width, and depth of merchandise.
  • Inventory rotation method, which is affected by the type of materials you store.
  • Storage and retrieval method.
  • Product turnover.
  • Weight requirements and load capacity.
  • The number of pallets or inventory items you keep in stock.
  • Do you expect to have to periodically reconfigure or disassemble your racking systems?
  • Is storage density your priority due to limited floor space?
  • Do you need additional pallet supports?

Before purchasing a racking system, you also need to determine the clear height of your warehouse. The clear height is the distance from the lowest point on the floor to the lowest-hanging object on the ceiling, such as a light fixture or fire suppression system. This ensures that your facility remains compliant with local building and fire codes.

Common Types of Pallet Rack Systems

Warehouse racking systems can increase organizational efficiency, worker productivity and increase the available space in your facility. There are several common racking options available, depending on your needs, including:

Selective Pallet Racking

The selective rack is the standard warehouse storage racking system. The selective rack is reasonably priced and highly configurable for budget-conscious operations where more space is available.

This system is selective because it allows the forklift operator to access every bay to pick pallets. Selective racks are not high-density systems, so they require more floor space than pallet racks.

Although not high density by default, placing one selective pallet rack behind another can create a double-deep pallet rack. This can be a cost-effective method of increasing storage density when other systems are either impractical or unavailable.

Bulk Storage Rack

Our Tennsco Bulk Storage Rack, available with either corrugated steel or particleboard decking, enables you to store heavy, bulky items on 14-gauge welded upright frames and beams. When the weight is uniformly distributed, the rack can support up to 3,800 lb.

To maximize space and versatility, the shelves are adjustable in 2” increments, allowing you to store various items. As the rack uses roll formed construction, it’s easy to assemble without tools.

Push Back Racking

A push back rack is a high-density storage system that uses the LIFO (last in, first out) inventory rotation method. While more expensive than selective pallet racks, push back systems allow you to maximize limited warehouse space because the racks are several pallets deep. In a push back rack, the forklift driver places a pallet on a nested cart that slides on inclined rails.

When a pallet is retrieved, the pallet behind it slides forward in preparation for unloading. Loading pallets will push the forwardmost pallet one position back. As you can load and unload bays from the same position, push back racks require less aisle space than other systems.

Pallet Flow Racking

A pallet flow rack is a high-density first in, first out (FIFO) racking system. When an employee loads a pallet from the rear of the system (the charge side), it flows forward on a series of gravity-fed rollers until it reaches the pallet stop in the front face of the rack (the discharge side).

Workers unload pallets from the front for distribution. Depending on the type of pallet flow rack, there may also be a braking system to ensure the pallet slows to a complete stop safely.

Due to the need for inclined roller or nested-cart lanes, push back and pallet flow racking systems require sufficient height to facilitate product movement. 

Carton Flow Racking

The carton flow rack operates on a similar principle to the pallet flow rack. However, while pallet-flow racks are designed to deliver palletized inventory, carton flow racks store cardboard boxes, cartons, and other small inventory items for human order pickers to retrieve.

Drive-In and Drive-Thru Pallet Racking

Drive-in pallet racking systems are storage systems designed to allow forklift operators to enter, load, or retrieve a pallet and reverse to exit. Drive-in pallet racks offer high storage density, allowing you to maximize the usable space in your warehouse.

Because drive-in racks use the FILO inventory rotation method, they’re unsuitable for perishable goods or highly varied merchandise where selectivity is necessary.

Drive-thru pallet racking systems are variations on Drive-In pallet racks that allow forklifts to exit by continuing through the system rather than reversing or turning to exit.

Cantilever Racking

Cantilever Racking

Cantilever racks are not designed to store pallets — they’re designed for storing long, oddly shaped, and heavy items. If you need to store lumber, bar stock, metal tubing, or furniture, cantilever racking is the ideal system for your facility.

The cantilever consists of an upright frame that rests on two bases. This provides the stability necessary to keep the rack secure. The cantilever rack has two arms that jut out from the uprights and cradle the inventory.

At Shelving + Rack Systems, Inc., we carry all-welded cantilever racks, available in mobile or stationary configurations. Each bay in our cantilever rack has a single-sided design that provides 15” of vertical storage space, accommodating a diverse range of inventory items.

Weighing between 150 and 221 lbs., depending on the variant, our cantilever racks use structural channel components and can support up to 1,500 lbs. per level (not to exceed 4,000 overall). The powder-coated finish ensures the rack won’t rust when left exposed to the elements, allowing you to use it for outdoor storage.

Roll Formed vs. Structural Racking

There are two primary production and assembly methods for warehouse racking systems: roll formed and structural.

Roll formed

Inexpensive, general-purpose, and standardized, roll formed racking is relatively simple to install, using beams that attach to uprights via teardrop-shaped holes. They’re also highly adjustable and configurable, allowing you to adapt to the changing warehouse and inventory conditions. However, roll formed rack uprights and beams are not as strong or durable.


Structural racking consists of hot-rolled steel components bolted together. More complex to manufacture and more difficult to assemble, structural racking is more expensive than roll formed racking. As the uprights and beams are bolted together, structural racks are harder to adjust or reconfigure.

However, structural racks are heavy-duty storage options. The increased strength allows them to support more weight. They’re also less susceptible to damage from forklift impacts.

Additional Precautions

Regardless of the fabrication and assembly method, racking systems are still vulnerable to collision. Additional precautions, such as column protectors, can absorb the impact from a forklift, preventing damage to the upright columns that can cause severe deflection. Attaching guard rails directly to the floor can also prevent forklifts from striking the upright frames.

Rack Finish

Rust can gradually weaken the uprights, beams, or bracing, leading to a loss in structural strength. If you want to use pallet racks outdoors, consider buying a rack that has a galvanized, powder-coated, or epoxy finish. This protects the steel rack from the weather and extends its lifespan.

Always Inspect Your Racks

Regardless of whether your pallet racks are used or new, you should conduct regular inspections to identify damaged components for repair or replacement. One or two forklift collisions can be enough to cause dangerous upright deflection, weakening the pallet rack’s structure.

Automated Systems

Automated systems are gaining an increasing foothold among warehouses that need to maximize efficiency, reduce workplace accidents, and increase storage density. However, automated systems are also expensive and may require modification to the layout of your warehouse.

Find the Right Storage System at Shelving + Rack Systems, Inc.

At Shelving + Rack Systems, Inc., we supply various racking system types for your warehousing facility or distribution center. The best racking system for your needs depends on several factors, from the dimensions, weight, and type of inventory you plan to store to your warehouse’s clear height and layout.

Call us at (800) 589-7225, and our design team can help you choose the right racking system for your facility.