Introduction
You get the photos from the buyer. Cartons spilled across the floor, a pallet leaning on the wall, product crushed at the bottom. The container arrived. The cargo did not arrive the way it left.
Pallet collapse in containers usually comes from a handful of repeat causes. The good news is that most are easy to fix once you know them. This guide covers six common causes and a practical fix for each. It draws on our experience supplying strapping to exporters in Rajkot and Morbi since 2012. We end with a short prevention checklist and FAQs.
What Pallet Collapse Looks Like
- Cartons slide off the pallet
- The stack leans or bulges
- Bottom cartons are crushed
- The pallet itself breaks
- The whole load falls against the doors
Each pattern points to a cause.
Cause 1: Weak or Wrong Pallet
The Problem
Low-grade timber, cracked boards, or a pallet too small for the load. The pallet fails first, and everything on top follows.
The Fix
- Use a pallet rated for the load weight
- Check boards and blocks before loading
- Make sure the load does not overhang
- Use heat-treated pallets marked for export
Cause 2: Poor Stacking Pattern
The Problem
Cartons stacked in columns, one directly on another, with no interlock. Columns are strong vertically but separate easily sideways.
The Fix
- Use an interlocking pattern for light cartons
- Keep the top surface flat
- Place heavier cartons at the bottom
- Do not let cartons overhang the pallet edge
A trade-off worth knowing: column stacking gives better crush strength, while interlocking gives better stability. For sea freight, stability often matters more, so strapping becomes essential when you column-stack.
Cause 3: Insufficient or Loose Strapping
The Problem
One strap around the pallet, or straps that are loose. The cartons move inside the strap, which only holds them after they have shifted.
The Fix
- Use at least two straps in each direction
- Strap through or under the pallet, not only around the cartons
- Use corner protectors so straps do not crush edges
- Tension properly with a tensioner
- Choose a width matched to the load, often 13mm to 19mm cord strap for pallets
Cord strap works well here because it stays firm and does not cut into cartons the way thin steel strap can.
Cause 4: Moisture and Container Rain
The Problem
Containers moving from humid Indian ports into cooler waters can build condensation, often called container rain. Wet cartons lose much of their strength. Bottom cartons crush, and the stack sags.
The Fix
- Use dry pallets with controlled moisture content
- Add desiccants in the container
- Use moisture-resistant cartons for long voyages
- Avoid loading wet goods or pallets
- Strap tightly so softened cartons stay in shape
This is the cause that surprises exporters most. A pallet that was perfect at the factory can fail weeks later because cartons absorbed moisture.
Cause 5: Voids and Load Shift
The Problem
Gaps between pallets let them slide and collide. Each impact loosens the stack a little more.
The Fix
- Load pallets tight against each other
- Fill gaps with dunnage bags or timber
- Strap rows of pallets together
- Brace the door end
Cause 6: Overstacking and Top Load
The Problem
Double-stacking pallets that were not designed to carry weight on top. The bottom pallet crushes.
The Fix
- Only double-stack when the bottom load can carry it
- Use a top board or sheet to spread the load
- Strap the upper pallet to the lower one
- Put lighter pallets on top
How Strapping Ties the Fixes Together
Most of these causes are made worse by poor strapping. Good strapping:
- Holds cartons in shape when they soften
- Keeps the stack as one unit during movement
- Ties double-stacked pallets together
- Lets pallets be strapped into rows
Here is a common pattern from the field. Exporters often blame the carton supplier first. But in many collapses, the cartons were fine. The stack was simply not held together.
Prevention Checklist
- Pallet strong and rated for the load
- Stacking pattern suited to transport
- At least two straps each way, properly tensioned
- Corner protectors in place
- Moisture controlled with dry pallets and desiccants
- Gaps filled
- Double-stacking only where safe
- Door end braced
How to Read the Damage Photos
Damage photos from the buyer tell you which cause to fix. Match the pattern:
| What You See | Likely Cause |
| Cartons slid off, pallet intact | Loose or too few straps |
| Bottom cartons crushed, stack sagging | Moisture or overstacking |
| Broken pallet boards | Weak or wrong pallet |
| Stack leaning in one direction | Voids and load shift |
| Whole row pushed against doors | No door-end bracing |
| Columns split apart | Stacking pattern without strapping |
Ask the buyer for photos from the door end before unloading. These show the load as it arrived, before handling changes it.
A Worked Example: Tall Carton Pallet
A pallet of 40 cartons, 1.8 m tall, weighing 650 kg.
What Went Wrong
- One strap each way around the middle of the stack
- No corner protectors
- Column stacking
- Loaded in monsoon season with no desiccant
What to Change
- Two to three straps each way, through the pallet deck
- 16mm or 19mm cord strap with matching buckles
- Corner protectors on all four vertical edges
- Interlock the top layers
- Desiccants in the container
Strapping Pattern for Export Pallets
- Place corner protectors on all vertical edges.
- Run straps through the pallet deck, not just around cartons.
- Place the first straps about 15 cm from each edge.
- Add a centre strap for long or tall loads.
- Tension each strap evenly with a tensioner.
- Lock with a buckle matched to the strap width.
Even tension matters. One tight strap and one loose strap let the stack twist.
FAQs
How many straps should a pallet have?
Most export pallets need at least two straps in each direction. Heavy or tall pallets need more.
Is stretch wrap enough?
Stretch wrap helps hold cartons together, but it rarely replaces strapping for heavy or tall pallets. Many exporters use both.
Which cord strap width is best for pallets?
13mm to 19mm covers most palletised cargo. Heavier pallets may need 25mm.
Can moisture really make a pallet collapse?
Yes. Wet corrugated cartons lose a large part of their strength, and bottom cartons are the first to fail.
Conclusion
Pallet collapse usually comes from weak pallets, poor stacking, loose strapping, moisture, voids, or overstacking. Fix those six, and most collapses stop. Review your next pallet against the checklist above, and if your strapping is the weak link, talk to us about the right width and buckle.
About Amass Strapping Solution
Amass Strapping Solution in Shapar, Rajkot, manufactures cord polyester strapping, wire buckles, and lashing tools that keep palletised export cargo stable from factory to destination. We have served exporters across Gujarat since 2012.
Speak to us today.