Glossary
Unidirectional base
Also called: parallel base, runner base, unidirectional bottom
Reviewed
Definition
A unidirectional base is a block-pallet bottom deck whose boards all run parallel in one direction, with no crosswise bottom boards. It is a full four-way design: forklifts and pallet jacks can enter from every side, though the pallet is stiffer and better supported along the board direction.
How it compares with other block bases
| Base | Bottom board layout | Entry |
|---|---|---|
| Unidirectional | parallel boards only | full four-way |
| Perimeter | frame around all edges | full four-way |
| Cruciform | frame plus center cross | full four-way |
| Overlap | boards in both directions, stacked | partial four-way |
Design notes
- Support differs by direction, so tell the designer how the pallet will sit on conveyors and rack beams
- Bottom board edges that pallet-jack wheels roll over should be chamfered
- Runner-type designs such as the CP1 to CP5 chemical pallets are related layouts
Why it matters
A unidirectional base uses fewer bottom boards than a perimeter base and still gives full four-way access. The trade-off is less support in one direction. See block pallet and runner.
Questions
- Is a unidirectional base pallet four-way?
- Yes. With no crosswise bottom boards, forklifts and pallet jacks can enter from all four sides.
Sources
- Uniform Standard for Wood Pallets (NWPCA, now Woodpack Global), 2012 edition
- CP pallets overview (Directpal)