Glossary
Block stacking
Also called: stacking, double stacking, column stacking
Reviewed
Block stacking is a warehouse storage method in which unit loads are stacked directly on top of one another on the floor, arranged in rows or blocks without racking. The pallets low in each stack carry the weight of every load above them, so stack height is a key design input.
How block stacking loads a pallet
In a block stack every pallet except the bottom one sits on the unit load below. That means:
- The bottom pallet's top deck carries the whole stack
- Higher pallets bear on the product underneath, so a stiff bottom deck spreads their weight over the boxes
- Soft or unstable loads (bags, flexible packaging) limit how high you can go regardless of the pallet
What buyers specify
| Field | Example |
|---|---|
| Stack height | stacked 3 or 4 unit loads high |
| Where | warehouse or in transit |
| Load per pallet | maximum and average |
Some retailers set stacking rules: Home Depot has asked for a safe load stacked 3 high, and BJ's for double-stackable loads. Confirm with the current vendor guide.
Block stacking vs floor stacking
Floor stacking is the support condition (a pallet on the floor, with or without loads above). Block stacking is the storage method that creates tall floor stacks. See unit load design.
Questions
- How high can pallets be block stacked?
- It depends on the pallet, the load's crush strength and stability. Specify the stack height so the pallet and packaging can be rated for it.