Designing a pallet around its load
A pallet design starts from the load, not the footprint. One long-established supplier lists eight things that set the spec: product weight, load distribution, lumber selection, deck configuration, handling equipment, storage systems, transportation conditions and reuse expectations.
1. Product weight
How heavy the load is per pallet, and whether it varies. The design carries the heaviest load, not the average one.
2. Load distribution
Whether the weight is spread across the deck, like cartons, or concentrated on a few points, like a machine’s feet or a drum’s chime. Concentrated loads need boards placed under the points.
3. Lumber selection
Hardwood or softwood, the grade, and whether it is dried. Hardwood is stronger and heavier; pine is lighter and holds fasteners differently. Dried lumber resists mold.
4. Deck configuration
How many deck boards, how wide and thick, the gaps between them, and the lead boards on the edges. Deck coverage, the share of the top that is wood, matters most for soft and small loads.
5. Handling equipment
Forklift or pallet jack, and from which sides. That decides two-way, notched stringers or a block build.
6. Storage systems
Floor-stacked, racked across beams, in drive-in racking or on flow rails. Racking puts the most demand on a pallet.
7. Transportation conditions
Truck, rail or container; how the load is secured; how it is wrapped. Loads that shift in transit hit the pallet hard.
8. Reuse expectations
One trip or many. A pallet meant to last many trips is built heavier and repaired; a one-way pallet can be lighter.
From answers to a drawing
With those eight answers, the design is drawn: stringers or blocks, member sizes, board counts, lumber and fasteners. The trade uses Pallet Design System software, PDS, to model a design against a target load, and some suppliers send a PDS sheet with every quote. Whether or not software is involved, the result should be a written spec you can order to again and again.
| No. | Member | What it does |
|---|---|---|
| 1 | Top deck boards | More of them, closer together, for dense or point loads. |
| 2 | Lead boards | Often specified thicker on a heavy build, since they take the first hit. |
| 3 | Stringers | Four or more, so the deck boards span less between supports. |
| 4 | Bottom deck boards | A fuller bottom deck spreads the weight on a floor or rack. |
Where to start
You don’t need all eight answers to ask for a quote. Size, weight and quantity are enough to start, and we ask about the rest.
A worked example
Take a load of 2,000 lb of boxed parts on a 48 x 40, racked across its stringers, lifted by forklift from the ends and by pallet jack on the floor. Weight and racking point to three stringers of a size that will span the beams loaded; pallet jacks from the ends mean no notches are needed; boxes spread across the deck mean seven top boards are probably enough; jack wheels mean the bottom deck must leave openings at the ends. The species and board thickness then come from the design check. Change one answer, say the jacks must come in from the sides, and the design changes to a block pallet.
What not to over-specify
Extra stringers, thicker boards and hardwood all add cost. They are worth it where the load needs them and wasted where it doesn’t. A design that starts from the load avoids paying for strength nobody uses.
Keeping the design
Once a design is settled, write it down: footprint, member sizes and counts, lumber, fasteners, notches, treatment. That record is what makes the next order the same as this one. It also lets a second supplier quote the same pallet if you want to compare.
When to revisit it
Change the design when the load, the handling or the storage changes: a heavier product, new racking, a new customer’s requirement. A pallet that worked for years may be wrong after a warehouse is re-racked.
Who does the design
For most loads, a pallet supplier designs the pallet from your answers. Large shippers sometimes have packaging engineers who specify pallets themselves, and some send their designs out to be checked. Either way, the result should be a sheet both sides can read.
Unit load thinking
A pallet, its load, the wrap and the bands are one unit load, and they behave together. A stiffer pallet lets cartons carry less; stronger cartons can sit on a lighter pallet. Researchers in unit load design treat them as one system, and the best designs come from looking at all three.
Try it before the big order
A new design is worth a trial before a large order: a few pallets, loaded with real product and handled the way your crew handles them for a week or two. Look for cracked lead boards, nails backing out and deck boards sagging between stringers. Small changes after a trial cost far less than a trailer of pallets that don’t suit the load.
Keep notes from the trial: which pallets failed, where, and under what. Dated photographs of a broken board with the load still on it tell the designer more than a description, and the next revision of the sheet can answer each failure directly, member by member. Bring the people who load and unload into that review; they see failures first and know the shortcuts.