Shipping pallet racking components without understanding freight classifications is one of the fastest ways to blow a warehouse project budget. Incorrect classifications lead to surprise surcharges, reclassification penalties, and even damaged industrial equipment arriving at your dock. Understanding pallet rack freight classifications before you place an order gives you the knowledge to plan shipments accurately, negotiate better rates, and protect your investment from the moment it leaves the manufacturer.
This guide breaks down how the National Motor Freight Classification (NMFC) system applies to warehouse racking systems, explains the four factors that determine where each component lands on the classification scale, and walks through the cost implications for upright frames, pallet rack beams, wire decking, and cantilever racking components.
Key Takeaways
- Freight classifications are determined by four main factors: density, handling requirements, stowability, and liability-each affecting shipping costs differently depending on the rack component.
- Different pallet rack components carry specific NMFC codes that directly impact what you pay per hundredweight for LTL shipping.
- Wire decking typically ships at lower freight classes because panels are compact, nestable, and easy to palletize.
- Cantilever racking arms and longer cross beams face higher classifications due to handling difficulties, poor stowability, and increased liability risk.
- Understanding classifications upfront helps avoid costly shipping surprises, prevents equipment damage, and supports more accurate project budgeting.
What Determines Pallet Rack Freight Classifications
Pallet rack freight classifications are standardized categories for shipping cost determination. Every component in a pallet racking system-from upright frames and horizontal beams to wire decking panels-must be assigned a freight class before it moves via less-than-truckload (LTL) carriers. National Motor Freight Classification (NMFC) categorizes pallet racks based on transportability, using a scale that runs from Class 50 (the lowest cost per pound) to Class 500 (the highest).
Unlike standard palletized goods that sit neatly on a warehouse pallet and stack uniformly, industrial pallet racks present unique shipping challenges. Upright posts can stretch 20 feet long. Cross beams are heavy, asymmetric steel members. Cantilever rack arms protrude at odd angles. These characteristics make pallet racking far more complex to classify than typical freight, and misunderstanding this complexity is where most shipping cost overruns begin.
Shipping costs are influenced by four key characteristics: density, stowability, handling, and liability. Freight classes dictate shipping rates and help prevent unexpected charges when you understand how each factor applies to your specific rack systems.
The Four Critical Classification Factors
Density: Refers to weight per cubic foot of a shipment. Components that pack more pounds into less space earn lower freight classes. Wire decking panels nested together on a pallet achieve high density, while tall upright frames with significant airspace between braces fall toward the lower-density end, pushing their class upward. Accurate measurement of the shipment is critical for proper freight classification, and density calculations must include the pallet, crating, banding, and any protective packaging.
Handling: Involves the care and equipment needed for safe loading and unloading. Long, heavy industrial racking components like 20-foot upright frames or cantilever arms require specialized equipment, extra labor, and careful maneuvering. Components with sharp edges or uneven weight distribution increase handling difficulty, which can shift a shipment into a higher freight class.
Stowability: Refers to the ease of packing freight into a truck or container. This factor considers whether components can be stacked, tiered, or placed alongside other freight without wasted space or restrictions. Pallet racks may face higher freight classes if they have poor stowability due to their dimensions. Long beams that span the full width of a trailer or cantilever arms that prevent efficient stacking reduce trailer utilization and increase class assignments.
Liability: Pertains to the risk of damage or theft during transit. This includes both the risk of damage to your rack structure components and the potential for heavy or sharp-edged pieces to damage adjacent freight. Coated or powder-finished components that scratch easily, extremely heavy single pieces that create balance risks, and protruding hardware all increase the liability factor.
Recent procedural changes from the NMFTA have placed greater emphasis on density for freight that does not present unusual handling, stowability, or liability concerns. For many standard rack components, density calculations now predict class with reasonable accuracy-but specialized or oversized pieces like cantilever arms still depart significantly from density-only assessments.
Read More: Maximizing Pallet Racking Weight Capacity: Essential Tips for Warehouse Efficiency
NMFC Classifications by Rack Component Type
Understanding which NMFC codes apply to each component in your warehouse racking project is essential for accurate cost planning. Two primary codes cover most pallet racking shipments. Freight requirements are only one part of procurement, and choosing the right pallet racking supplier for your warehouse needs can help ensure component specifications, availability, and project requirements are considered before an order is placed.
NMFC 164340 applies to metal warehouse or pallet racks: Parts or sections thereof, not otherwise included (NOI), with or without components of other materials, in packages. This is the broad classification covering upright frames, pallet rack beams, braces, row spacers, and most structural rack components. Because this code encompasses so many types of pallet racking, there is no single fixed freight class-the assignment depends on density, packaging configuration, and the specific characteristics of what you’re shipping.
NMFC 164150 is specific to wire decking or shelving: iron or steel wire decking for warehouse or industrial storage, with or without reinforcement, in packages. This more specialized code applies to wire decking used across various types of pallet racking, from selective pallet rack systems to double deep pallet racking configurations.
Wire Decking panels are among the easiest rack accessories to ship efficiently: Wire decking enhances airflow and provides additional support within pallet racking systems. Load capacity varies based on the deck design, dimensions, support configuration, and manufacturer specifications. From a freight perspective, wire decking prevents pallets from falling through racks and allows for sprinkler access in warehouses-but its shipping advantage lies in its flat, nestable profile. Nested in bulk, the density improves further. Packaging affects the class assigned to a shipment, especially in pallet rack freight, so how you stack and secure wire decking panels directly influences your shipping costs.
Standard Beams (step beams, box beams, and horizontal beams): Long, heavy steel members that typically span 8 to 12 feet. Under NMFC 164340, depending on density, dimensions, packaging, and applicable NMFC requirements, pallet rack beams may fall within different freight classifications. However, beams that ship without skids, without end protection, or in awkward configurations see their class pushed higher due to increased handling and liability concerns. The weight capacity and profile of each beam affect how many can be safely bundled, which in turn affects density.
Upright Frames are the vertical supports of any pallet racking system: Frames ranging from 10 to 20 feet tall with depths of 30 to 60 inches create significant airspace, reducing density. Their length tests stowability limits inside standard trailers (often 102 inches of inside width). When shipped individually or loosely bundled, tall or oversized upright frames may receive higher freight classifications due to their dimensions, density, and handling requirements. Spliced frames, footplates, and diagonal braces add handling complexity.
Cantilever Rack Arms Require Additional Freight Planning: Cantilever rack arms have a unique shape that can require additional consideration during shipping. Their dimensions and configuration may affect stowability, handling requirements, and freight classification. However, those same protruding arms that make cantilever racking effective in warehouse storage make the components extremely difficult to ship. Arms are not nestable, frequently exceed standard dimensional limits, and create dangerous protrusions during transit. Even under the same NMFC 164340 code, cantilever arms attract significantly higher class assignments than standard beams due to their poor stowability and increased handling risk. Cantilever racking can be single- or double-sided, and shipping configurations differ accordingly.
Common Mistakes When Determining Classifications
Assuming all rack components ship at the same freight class: Because NMFC 164340 covers many different component types under the NOI designation, shippers sometimes apply one class across an entire order. This ignores the substantial differences between compact wire decking panels and 18-foot upright frames. Uprights will almost always carry a higher class than items stored on a flat pallet.
Failing to account for packaging and bundling requirements: Long steel members without proper banding, edge protection, or skids shift freight into higher classes due to liability and handling difficulties. Improper bundling can make beams or frames exceed allowable lengths or create hazardous protrusions, triggering surcharges. Classification errors can result in additional shipping charges and operational issues.
Not considering how component dimensions affect trailer utilization: Density calculations must include pallets, crates, and wrapping. A wire deck on a pallet adds volume and weight-if packaging increases overall volume more than weight, the effective density drops, pushing classification upward.
Underestimating freight class for longer components like cantilever arms: Cantilever arms that protrude beyond standard pallet dimensions drastically reduce stowability. Even when classified under the same NMFC code as standard pallet rack beams, their effective freight class will be notably higher.
Relying on outdated classification data: The NMFC system is not static. Docket proposals, class changes, and code updates shift where certain items fall. Using outdated thresholds leads to inaccurate quotes and budget shortfalls. Understanding freight classifications aids in optimizing packaging and reducing costs-but only when the classifications you reference are current.
Freight classifications can change over time, making it equally important to understand the key questions to ask before buying an industrial racking system so shipping requirements are considered alongside storage capacity, configuration, and operational needs.
Cost Impact and Shipping Strategy Considerations
Freight classification influences the efficiency of warehouse operations and shipping costs at every stage of a racking project. Lower classes yield lower cost per pound for LTL shipping; higher classes increase costs substantially due to the combination of lower density, higher liability, and poor stowability.
LTL versus Flatbed Shipping: Standard LTL works well for wire decking, shorter beams, and hardware components that fit within dimensional limits and can share trailer space. However, very long upright frames, cantilever arms, or oversized industrial shelving components may exceed LTL dimensional limits entirely. Flatbed or over-dimensional shipments are quoted differently and may require permits or overhang allowances. Knowing which components need flatbed shipping before you order prevents timeline disruptions and surprise costs.
Bundling and Packaging Optimization: Organized bundling reduces handling complexity and improves stowability. Proper packaging and bundling can influence freight classification and help protect racking components during transportation. Factors such as component dimensions, protective packaging, bundle configuration, and handling requirements should be evaluated when preparing pallet rack shipments.
How Shipment Density Affects Freight Class: Shipment density is another important factor in freight classification. Compact packaging and efficiently arranged components generally use trailer space more effectively, while oversized or irregularly shaped shipments may receive higher classifications.
Different Components Affect Shipment Classification: Different pallet rack components may fall under different freight codes or classifications. Wire decking, beams, upright frames, and cantilever components can vary considerably in density and handling requirements, so mixed-component shipments may be evaluated differently from shipments containing similar components.
Project Budgeting and Timeline Planning: Pallet racking systems optimize warehouse space and enhance efficiency, but only if the components arrive on budget and on schedule. Understanding freight classifications before the procurement phase lets you build realistic shipping costs into your project plan. For large installations involving selective racking systems, drive-in pallet racks, or pallet flow racks, the cumulative impact of freight classification on total project cost is significant.
For projects with strict delivery schedules, understanding how U.S. inventory supports time-sensitive racking projects can also help warehouse teams account for product availability when coordinating procurement and installation timelines.
Selective pallet racking is one of the most widely used warehouse storage systems because it provides direct access to individual pallet positions. It allows access to every pallet without moving others, and selective racking allows 100% access to all stored loads. Selective racking systems are inexpensive per pallet position, supporting First-In, First-Out (FIFO) inventory management and efficient inventory turnover. This popularity means selective racking components are among the most frequently shipped and the most important to classify correctly.
Beyond standard selective pallet racking, specialized warehouse racking configurations may present different freight considerations depending on their component size, weight, and packaging requirements. Systems that incorporate longer structural members, rails, rollers, or additional framing may require different handling and shipping arrangements. Drive-in pallet racks allow forklifts to enter the racking structure directly, and their upright posts and horizontal rails are heavier and longer than standard selective components. Drive-in pallet racks eliminate aisles for denser storage, but their structural members are more challenging to ship. Pallet flow racks use gravity rollers for inventory rotation and can hold up to 20 pallets deep in one lane-but the inclined rails and gravity rollers themselves add shipping complexity. Push back pallet racking allows pallets to be stored up to six deep, with specialized carts and rails that require careful packaging. Multi-tier racking maximizes vertical space in warehouses, and its multiple levels of framing increase the volume and weight of shipments.
High-density storage configurations-including pallet flow, push back, and drive-in systems-can increase storage capacity substantially, which means larger component orders and more freight to classify correctly. Dynamic pallet racking enhances operational efficiency through automation, but the specialized components involved may require unique classification approaches.
Read More: Pallet Racking 101: Safety, Efficiency, and Growth Strategies
Planning Freight for Pallet Rack Components
Understanding how density, handling, stowability, packaging, and component dimensions affect freight classification can make warehouse racking projects easier to plan. Different components may require different shipping considerations, so reviewing these factors early can help businesses anticipate transportation requirements and avoid unnecessary complications during delivery.
BHD Storage Solutions provides warehouse storage solutions designed around different operational needs, including heavy-duty industrial pallet racks for demanding storage environments. Facilities handling long or oversized materials can also consider cantilever rack systems, while wire deck can add support and visibility within pallet racking. A range of pallet rack accessories is also available to support an efficient setup. If you are planning a new system or upgrading an existing one, contact us to discuss your warehouse storage requirements.
Frequently Asked Questions
What freight class do pallet rack uprights typically fall under?
Upright frames generally fall under NMFC 164340 and ship at Class 70 or above. Taller frames (12–20 feet) with significant depth often move into the Class 100–125 range because their size creates low density relative to volume, they are difficult to handle, and their length limits stowability inside standard trailers. Proper packaging and skidding can help keep the class toward the lower end of that range.
Why does wire decking usually have a lower freight class than beams?
Wire decking can qualify for a lower freight class because its flat profile allows panels to be packaged efficiently and achieve relatively high shipment density. Actual classification can still vary based on packaging, quantity, dimensions, and current NMFC requirements.
How do cantilever rack arms compare to standard pallet rack beams for shipping?
Cantilever rack arms may receive a higher freight classification than standard pallet rack beams because their shape and dimensions can require additional handling and trailer space. Actual shipping costs depend on the shipment configuration, carrier, dimensions, and applicable freight classification.
Can improper freight classification void damage claims?
While improper classification may not automatically void a damage claim, it weakens your position substantially. If a carrier determines that freight was misclassified-especially if the actual class indicates higher liability or handling requirements-they may argue that inadequate classification contributed to the damage. Accurate measurement of the shipment and correct NMFC code assignment are essential for protecting your claim rights.
What’s the difference between NMFC 164340 and NMFC 164150?
NMFC 164340 is the general code for metal warehouses or pallet racks, parts, and sections not otherwise included-covering upright frames, beams, braces, and most structural components. NMFC 164150 is specific to wire decking and shelving made of iron or steel wire for industrial storage. Wire decking classified under 164150 often receives more predictable class assignments, while components under 164340 can vary widely based on density, dimensions, and packaging.
Should I ship rack components together or separately for better rates?
In most cases, separating components by type yields better rates. Shipping wire decking together allows the entire shipment to benefit from the lower classification under NMFC 164150. Mixing wire decks with upright frames or cantilever arms on the same pallet often causes the shipment to default to the highest class item, increasing your overall cost. For large warehouse racking projects, plan shipments by component similarity to optimize classification and keep labor costs associated with freight manageable.
