How to Determine Industrial Warehouse Shelving Capacity

high density pallet racking system

Pallet racking systems are necessary for maximizing the storage space of your warehouse. Calculating the correct load capacity of your warehouse storage systems is critical to your workplace’s safety and efficiency.

Exceeding the rated load capacity of your racking system increases the risk of rack collapse, which can cause serious injury or death. It can also cost you significantly in property losses. Avoid these hazards by knowing exactly what your pallet rack capacity is at all times.

Where to Start

There are several points to consider before measuring your pallet racking systems. First, consult the rack manufacturer or supplier regarding the load capacities of the various components if you don’t have access to this information. This is especially important if you adjust, reconfigure, or dismantle the racking system for relocation.

In addition, when you have the load capacity information, it’s important to keep in mind that the rated capacity only applies if the loads are properly positioned on the beams. In other words, the load must be evenly distributed along the beams.

If the load is improperly placed on the rack beams, the weight distribution will be asymmetrical, causing the system to become unbalanced because one upright is under more stress than the others.

Always ensure your pallet racking systems are correctly assembled. If you’re using structural racking, all parts should be assembled by trained professionals.

Pallet Rack Beams

The beams provide the horizontal support structure of your pallet rack; the forklift driver places the pallets directly on these parts. As a result, you need to know the load capacities of the beams to allow for the safe loading and unloading of inventory using material-handling equipment.

Rack manufacturers list the load capacities of the beams per pair. That is, the listed load capacity is per beam level, not per beam. If you need to load two pallets weighing approx. 1,000 lbs. each, for example, the load capacity per pair must be at least double, or 2,000 lb., at a minimum.

Consider the types of pallet loads you intend to store. The length or width of the beams must be compatible with the dimensions of the pallets while also providing sufficient clearance for both safety and forklift access. If you need to store pallets that are 48” in width, for example, you’ll need to multiply that number by two for a total of 96”. Next, add 12” clearance for safety and increased forklift access.

Frame Capacity

The frame of a pallet racking system consists of uprights (vertical columns). Several factors directly affect the load capacity of the upright frames. These include the vertical space between the beams, called vertical beam spacing, the height of the system, and the number of beams.

The fewer beam levels (pairs), the less weight the pallet rack can support overall. The more beam levels, the more stable and structurally reinforced the rack uprights are, supporting more weight. Many pallet racking systems are roll formed, using teardrop- or keyhole-shaped slots in the uprights for assembly. This allows you to adjust the height of the beams, configuring the system as needed.

If you choose to use structural racking, which is welded or bolted, the rack components are generally more robust and durable, as they’re hot-rolled and heavy gauge.

Height-to-Depth Ratio

You should also consider the height and depth of your pallet racking system and how these values relate to each other. According to the Rack Manufacturers Institute (RMI), the height of the pallet rack should not exceed the depth by more than a 6:1 ratio unless the rack has external anchoring or bracing. This ensures adequate stability.

Proper Anchoring is Critical

Always anchor your pallet racking frames to the concrete floor of your warehouse to ensure maximum lateral stability. Anchors are mechanical fasteners that securely attach the uprights to the floor, preventing sway or collapse. In conjunction with column protectors, anchoring also reduces the risk of rack collapse resulting from forklift collisions.

Damage to the uprights from impact can compromise the structural stability of the rack, reducing the load capacity. To identify the damage and replace or repair damaged components, it’s worth conducting periodic inspections of your pallet racking systems.

Deduct the Weight of the Racking Systems

The weight of the racking system plays a role in the load capacity. Deduct the weight of the rack components (uprights, beams, decking, and other accessories) to find the correct load capacity for the system as a whole.

Racking Systems

Display Load Capacity Information

Once you have the needed information regarding load capacities for the beams and upright frames, whether from your own calculations or as the result of contacting the manufacturer, you must display this information.

Print this information and place placards at the ends of racking systems, ensuring they’re visible at all times. Your workers should always be aware of the load capacities of every storage system in your warehouse.

Contact Shelving + Rack Systems Inc. for Your Storage Needs

At Shelving + Rack Systems Inc., we understand the importance of knowing the correct load capacities for your warehouse storage systems. For your safety, we always supply accurate information regarding our shelving and racking systems.

If you need information regarding a product in our catalog, including rated load capacities, give us a call at (800) 589-7225.