Pallet Rack Modifications: How They Affect Load Capacity

Posted on July 19, 2022 - updated on December 11 2023 
Shayne Caza

Pallet racks are very flexible and versatile structures. They offer the possibility to place beams at various heights to accommodate all kinds of materials and goods. However, as a warehouse owner or manager, you must be cautious when modifying an existing pallet rack system since one slight change can significantly alter its strength and structural integrity.

All pallet rack owners must have their racks’ load application and rack configuration (LARC) drawings on hand. These documents outline the maximum allowable weight that can be supported on each beam level for specific configurations. If a configuration is changed, the LARCs are no longer valid, and the pallet rack capacity has most likely been altered.

This blog post goes over 4 common rack modifications that can affect your pallet racks more than you may think.

1. Altering the beam configuration

With the way beams seamlessly clip in and out of their compatible uprights, it could be very tempting to move them around, add/remove them to accommodate different loads, or increase storage space. However, such changes will most likely impact the rack’s load capacity. The example below demonstrates how the capacity of your rack could be drastically reduced by removing just one beam level to make room for larger loads.

pallet rack modifications like changing beam levels can affect load capacityFigure 1. Removing a beam level can drastically reduce a pallet rack’s load capacity

For this reason, rack modifications should always be done under the supervision of a professional engineer. Every time a change is made, updated load capacities should be calculated and displayed to maintain safe operations. Failure to do so could lead to extremely dangerous situations, like a collapse.

2. Replacing pallet rack components

The most common mistake we see in warehousing is replacing a single damaged upright with another one without considering if it is the same. It may look the same, but the steel gauge (thickness) is often overlooked. This greatly impacts the load capacity and creates a weak spot in your system, which is now prone to collapse.

When beam components are damaged, the most effective solution is to replace them. In such cases, verifying that the replacing beam is identical to the previously used one is important. One issue is installing a beam that is incompatible with the uprights being used. Assembling incompatible beam types and uprights could greatly reduce the lateral stability of your rack system. Furthermore, any dislodging caused by inadequate connections between beams and uprights could lead to undesirable incidents.

Installing a replacement beam that differs in shape, size, or thickness from the original part will also affect the rack's load capacity.

Because of these possible issues, replacing any component with identical replacement parts is recommended. When in doubt, it is a good idea to contact your original equipment manufacturer (OEM) or a rack expert to confirm the compatibility of your pallet rack components.

Incompatible rack components
Figure 2. Incompatible components

3. Adding rack upright extensions

Multiple warehouses have added upright extensions to accommodate an additional beam level.
Don’t think about doing that in your warehouse unless you first consult with the OEM or a professional rack design engineer! And don’t load the racks until you’ve received signed and stamped updated LARCs. Without these recommendations, you could overload the existing rack, change the seismic behavior, and void the OEM’s warranty, leaving you without recourse.


4. Resorting to various rack repair options

All approaches to rack repair are not created equal. Racks are highly optimized structures that need all their parts in working order. Don’t improvise; call upon professionals.

Homemade repairs

Homemade repairs, self-repairs, in-house repairs, DIY repairs: no matter what you call them, these repairs are discouraged since they often fail to meet the requirements outlined in the design codes. For instance, the Guidelines for the Assessment and Repair or Replacement of Damaged Rack issued by the Rack Manufacturers Institute (RMI) in the United States say that all welding should be performed by a certified welder and overseen by a qualified professional engineer.

It is also important to meet the appropriate specifications outlined by the American Welding Society (AWS), such as in AWS D1.1, where factors such as operating temperatures and surface conditions must be considered. Inadequate welds can lead to dangerous situations since the rack’s load capacity has most likely been altered. For more information, read our article Field Welding on Racks - Why Homemade Repairs May be Risky and Unsafe.

Homemade repairs, such as the ones shown in Figures 3 and 4 below, are inadequate.

Inadequate field welding Inadequate homemade rack repair
Figure 3. Inadequate field welding Figure 4. Inadequate homemade rack repair

Rack repair kits

Rack repair kits are more reliable for addressing damage to upright columns or braces. Engineered rack repair kits like Damotech’s permanently repair and protect racks without decreasing load capacity. Designed and certified by engineers, they provide warehouses with a safe, heavy-duty solution to rack damage. On top of that, they can adapt to various rack configurations; their quick installation will reduce downtime and save you from having to unload most, if not all, the pallets.

When faced with a damaged pallet rack component, there are 2 recommended courses of action: replace or repair. The first solution completely replaces the damaged component with an identical replacement part. The second is to repair the rack with an engineered rack repair solution. Damotech’s column repair kits can be a good alternative to replacing entire uprights and will restore the rack’s original load capacity while making it much more resistant to future impacts. Our adjustable brace is a quick and easy solution to replacing damaged or missing horizontal or diagonal braces.

Rack repaired with a DAMO PRO
Figure 5. This column was repaired with a DAMO PRO. Its capacity has, therefore, been restored.

Key takeaways on how rack alterations affect load capacity

The key point to take away from this article is that any modification made to a pallet rack will likely affect its load capacity. Therefore, a qualified racking expert should always be consulted beforehand. It is important to follow the configurations displayed on your LARCs. Any deviation from them will invalidate the load capacities displayed, and a re-evaluation will be necessary.

Lastly, rack repairs should always be performed with the help of professionals to ensure the complete restoration of a pallet rack’s capacity.

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Welcome to the world of Damotech, the first and largest rack safety solutions specialist in North America. With its lines of rack protection and repair products, Damotech strives to put an end to the endless cycle of upright replacement by focusing on warehouse safety and the permanent elimination of recurring rack damage. Through our engineering services, we will help create a safer working environment for you and your employees, bringing you true peace of mind while saving you money in the process.