Unit load
Also called: palletized load, pallet load
A unit load is a group of items, usually cases on a pallet or slip sheet, secured together so it can be stored and moved as a single unit by a forklift or pallet jack. It includes the pallet, the packaging, the stacking pattern and the stabilizers.
In depth: Unit load design: designing the pallet, packaging and load together
A unit load is the thing a warehouse actually handles: the pallet, the cases or bags on it, the stacking pattern, and whatever holds it together (stretch wrap, strapping, edge protectors, tier sheets).
What a unit load includes
| Part | Examples |
|---|---|
| Base | Wood, plastic or paper pallet, or a slip sheet |
| Packaging | Corrugated cases, bags, pails, drums, bulk boxes |
| Arrangement | Cases per layer and layers (ti-hi), column or interlock |
| Stabilizers | Stretch wrap, straps, corner boards, top frames |
Why it matters for pallet design
The pallet and the packaging behave as one system. Wide gaps between deckboards and a soft, sagging deck reduce the compression strength of the cases above. A stiff load can carry part of its own weight across the supports (load bridging). Designing the pallet without the load, or the packaging without the pallet, usually over-builds one of them. The unit load design guide covers the method.
How it appears on a spec sheet or RFQ
PDS has a separate Unit Load Specification. A published PDS example lists corrugated boxes 16 × 12 × 10 in, 20 lb each, 10 per layer, 5 layers interlock-stacked, 1,000 lb (454 kg) total and a 50 in (1270 mm) load height. For an RFQ, give the case dimensions and weight, cases per layer, layers, overall height, total weight and the stabilizers used.
Common confusions
"Load" alone can mean the weight on a single pallet or a full truckload. A unit load is always one handling unit.
Related
- GuidesUnit load design: designing the pallet, packaging and load togetherUnit load design treats the pallet, packaging, stacking pattern and stabilization (wrap, straps) as one system instead of designing each separately. A stiffer pallet lets boxes keep more compression strength; a rigid load helps a pallet carry more in racking. Designing them together often saves material on both.
- GlossaryStacking patternA stacking pattern is the arrangement of cases on a pallet: how they are placed within each layer and how each layer relates to the one below. The main choices are column stacking, which maximizes box strength, and interlocking patterns, which improve stability.
- GlossaryStretch wrapStretch wrap is a thin, elastic plastic film, usually linear low-density polyethylene, wound tightly around a unit load under tension. It holds the cases together and to the pallet so the load stays stable in handling and transit.
- GlossaryLoad bridgingLoad bridging is the effect of a stiff unit load spanning across the pallet's weak points, so the packaged product carries part of the load and the pallet deflects and stresses less than it would under a flexible load of the same weight.
- GlossaryWhat is ti-hi?Ti-hi describes how cases are stacked on a pallet: the ti is the number of cases in each layer and the hi is the number of layers. Ti times hi gives the cases per pallet; for example, a 10 × 5 ti-hi is 50 cases.
- CalculatorsCases per pallet (Ti-Hi)Cases per layer, layers, total cases, load height, gross weight and cube utilization for any case and pallet size, with the layer pattern.
More in Performance and engineering
- GlossaryConcentrated loadA concentrated load is a load that bears on one or a few small areas of the pallet deck instead of spreading over it, such as drums, machinery feet or a coil. It usually gives a much lower safe load than the same weight spread evenly.
- GlossaryCreepCreep is the gradual increase in a pallet's deflection while a load stays on it over time. Wood creeps, and plastic creeps much more, especially when warm, so racked pallets sag more after days or weeks than when first loaded.
- GlossaryDeflectionDeflection is the amount a pallet bends or sags under load, measured at the point of greatest movement. Racking limits are commonly about 2% of the span, and automated systems often require 0.5 in (13 mm) or less.
- GlossaryDurabilityDurability is a pallet's ability to survive repeated handling, measured as the number of trips or handling cycles before it needs repair or is scrapped. It is driven by fastener quality, lead board width, member thickness and species density.
- GlossaryDynamic loadDynamic load is the weight a pallet can safely carry while it is being moved, supported on forklift tines, a pallet jack or a conveyor. It sits between the static rating and the racking rating.
- GlossaryLoad capacityLoad capacity is the maximum weight a pallet can safely carry under a stated support condition. It is always quoted per condition: static (on the floor), dynamic (on forks or a pallet jack) and racking (spanning rack beams), and the racking figure is usually the lowest.
Last reviewed 2026-09-24. 264 words.