Pallet boxes: choosing the right size, strength and design

Start with the footprint

The footprint is decided by the pallet, not by the product. In the UK that is usually a 1200 x 1000mm or 1200 x 800mm pallet, and the box normally sits a few millimetres inside the deck so nothing overhangs. Overhang is the single biggest cause of crushed corners, because a proud edge takes the knock from every other pallet, forklift and racking upright it meets.

Usable internal dimensions

The internal size is always smaller than the footprint, and by more than people expect. Triple wall board is thick, so a triple wall sleeve takes roughly 15 to 20mm off each internal dimension compared with the outside. Add any liner, frame, layer pad or bag and the usable space shrinks again.

Tell us the product dimensions and how many you want in a box, and we will work back to the external size. Working the other way round, from a footprint you have been given, is how loads end up not fitting on the last layer.

Construction: base, sleeve and cap

• Base tray: a shallow tray that locates on the pallet and takes the weight of the load. Fitted with a top flap or bottom flap depending on how it is filled.
• Sleeve: the vertical wall. A four-panel sleeve with a glued or stitched joint is the usual choice, and the height can be changed without changing anything else in the pack.
• Cap: the lid, which drops over the sleeve and protects the top layer from dust and from the pallet stacked above.
• Full case: base and sleeve made as one piece, which is quicker to pack but fixes your height and takes more storage space flat.
• Internal frame, partitions and layer pads: used when the load will not support itself, or when layers need separating for handling.

Loading access

How the box is filled changes the design more than anything else. A sleeve that can be dropped over a loaded pallet suits heavy items placed by forklift or hoist. A box with a drop-front or hinged panel suits hand loading of long or awkward parts, because nobody has to lift over a full-height wall. Where a load is built up in layers, a base and sleeve with layer pads is usually quicker than any single case.

It is worth watching the pack being filled once before the design is fixed. Small changes, a hand hole, a shorter sleeve, a pad instead of a partition, often take more time out of the operation than a cheaper board ever will.

Strength and stacking

Corrugated takes its stacking strength from the vertical walls, so anything that interrupts a wall (a hand hole, a drop front, a printed window) reduces it. Height matters too: the taller the sleeve, the more it wants to bow outwards under load. Humidity reduces compression strength significantly, which is why a pack that is fine in a dry warehouse can fail in an unheated yard or a long sea journey.

Weight ranges are indicative only. Final board specification depends upon box dimensions, product weight, distribution conditions, stacking requirements and environmental conditions.

Securing the load

• Strapping through the pallet, in two directions, holds the cap and sleeve down onto the base.
• Edge boards under the straps stop the strap cutting into the top edge of the cap.
• Stretch wrap keeps dust out and holds the bottom of the sleeve to the pallet, but does not add stacking strength.
• Corner posts help where pallets are handled repeatedly or stored outside racking.

Where we come in

We manufacture pallet boxes, sleeves, caps and internal fittings to size at our Letchworth Garden City site, so the box is built around your load rather than the nearest stock option. We can hold agreed quantities in our BRCGS Storage and Distribution certificated warehouse and release them against your schedule, which is usually how pallet boxes are bought once a design settles down.

Send us the product dimensions, the weight per pallet, how it is loaded and whether the pallets will be stacked, and we will come back with a specification and a run rate that makes sense.