How Dunnage Solves Shipping Damage

In international shipping, protecting cargo from shifting and impact is a constant challenge. Dunnage – the specialized packing and bracing materials used to stabilize loads – plays a crucial role in this process. Dunnage materials (from wooden blocks and air-filled bags to bubble wrap and foam) fill empty spaces in containers, trucks, and railcars to secure freight. By properly using dunnage in shipping, companies can dramatically reduce damage. In fact, industry sources note that properly braced cargo has a much lower chance of breakage in transit. For example, when goods are tightly cushioned and wedged, accidents and losses drop significantly. This article explains what dunnage is, why it matters, the types of dunnage, and how to choose the right dunnage, so goods arrive safely.

What is Dunnage?

The term dunnage refers to any material used to support, protect, or secure cargo during transportation. In practice, dunnage can include wooden beams or blocks, inflatable airbags, molded plastic inserts, foam padding, bubble wrap, kraft paper, and more. Essentially, dunnage fills empty spaces and bears the forces on goods so that the cargo itself does not move or get crushed. For example, Inbound Logistics defines dunnage as “any material used to support or elevate cargo to protect it from damage during transport. These materials create a stable buffer: for instance, wooden boards can elevate heavy machinery off a trailer deck (allowing forklift access), while bubble wrap or airbags inside a crate cushion delicate items.

Why Dunnage Matters in Shipping

Proper dunnage is critical because even a small shift in cargo can cause serious damage. During transit (by road, sea, or rail), freight can experience strong vibrations, sudden stops, or rough handling. Dunnage prevents movement and absorbs shock, acting like a protective barrier for the goods. As one logistics expert puts it, dunnage “prevents items from moving and helps to absorb shock” during handling and transportation. This shock absorption prevents fragile or loose products from colliding or falling, significantly reducing breakage. In practical terms, companies “fill any voids” between loads with dunnage to lock the shipment in place.

For perspective, industry data show that hundreds of millions of containers move each year, and the costs of cargo loss can exceed $50 billion annually. Inadequate securing (no dunnage or poor stuffing) accounts for much of this loss – roughly 65% of damage is due to incorrect lashing or stuffing. The table below highlights these figures:

Most shipments do arrive intact (industry estimates carrier damage rates around 1–3%), but even a few percent translates to huge losses. Dunnage solves many of these problems: in practice, companies fill all voids with dunnage (timber beams, pallets, foam, or airbags) to keep cargo locked in place. By doing so, goods remain stationary and cushioned, which greatly reduces breakage claims and damages.

Types of Dunnage Materials

There are many types of dunnage materials, chosen based on the cargo and transit mode. Common examples include:

• Wooden Dunnage (beams, blocks, planks): Durable hardwood or softwood boards (e.g., 2×4, 4×4, 4×6, up to 8 ft long) used under heavy pallets or steel coils. Wood dunnage is common in flatbed shipping, providing a stable base or raising cargo for forklift access. On open decks, wood boards lift the load off the trailer deck for easier loading by crane or forklift. Beveled wood blocks can also prevent cylindrical loads from rolling.

• Plastic Dunnage and Airbags: High-density plastic materials (like molded pallets or crates) are common in food and beverage freight. Another form is inflatable dunnage bags – heavy-duty vinyl or polyethylene bags placed between pallets or cargo. When inflated, these airbags fill large voids and lock goods in place. For example, carriers often insert plastic airbags between stacked pallets to prevent any jostling during transport. This plastic dunnage is lightweight, reusable, and cost-effective for many shipments.

• Foam, Bubble Wrap, and Paper: For smaller or fragile items, lightweight fillers cushion shipments. Foam-in-place, corrugated or kraft paper, and bubble wrap absorb shocks from multiple directions. Bubble wrap is a common dunnage for electronics and glassware, while crumpled paper or molded pulp can be balled or layered inside boxes. These soft dunnage materials effectively act as miniature shock absorbers, preventing damage to delicate cargo.

• Flatbed-Specific Dunnage: On open trailers or rail flats, sturdy wood blocks or metal stands (known as flatbed dunnage) are placed under the load. They lift cargo a few inches above the deck, creating space for forklifts or cranes to handle it. This prevents the load from contacting the floor and keeps it from shifting on an open deck.

Flatbed shipments often rely on wood dunnage (as shown above) to raise heavy cargo and allow forklifts to slide in underneath. By lifting loads a few inches, these dunnage blocks prevent direct contact with the trailer floor and let crews access the cargo from the sides. Proper flatbed dunnage ensures stability during transit, keeping heavy loads from sliding or tipping on an open deck.

In a shipping container or box truck, dunnage materials fill voids to brace goods on all sides. The image above shows wooden beams holding a heavy coil in place. Dunnage in shipping containers effectively “fills any voids” and prevents cargo from shifting. Even small gaps are dangerous in transit, so every space should be padded or blocked. By using suitable dunnage (timber planks, pallets, inflatable bags, etc.), shippers lock all boxes and crates into position and greatly reduce the chance of damage.

For smaller parcels or delicate goods, softer dunnage like bubble wrap, foam, or recycled paper is used. These materials cushion the product surface and absorb shocks. For example, a glass vase might be surrounded by air pillows or bubble wrap so it cannot move or break inside the box. In this way, even lightweight dunnage materials prevent shipping damage by acting as miniature shock absorbers. Matching the dunnage type to the fragility of the cargo is key to preventing returns or delays.

Choosing the Right Dunnage

Selecting proper dunnage depends on the cargo and the transport mode. Key considerations include:

• Cargo characteristics: Heavy or bulky freight (like machinery or steel coils) needs rigid, strong dunnage (wood blocks or metal braces). Fragile or small items (electronics, glassware) require a softer filler such as foam or bubble wrap.

• Transport mode: Flatbed trailers generally require wooden dunnage blocks (flatbed dunnage) to lift and space loads. Enclosed trailers and containers can use lighter materials and airbags since the load is already enclosed.

• Fill all voids: Regardless of material, fill every space. Even one unfilled gap can allow shifting. Experts advise to "fill any voids" with dunnage (timber beams, pallets, foam, or airbags) so cargo is locked in place.

• Planning and communication: Carriers usually carry some standard dunnage (open-deck trucks often have 6–10 wood pieces on board). But specialized dunnage (like large airbags or treated wood) may not be provided. If you need specific dunnage (e.g., extra airbags or pest-free wood), request or supply it ahead of loading.

• Regulations: Many countries (and even some states) regulate dunnage to prevent pests or contamination. For example, California enforces “strict regulations on dunnage materials to prevent pest infestations, so untreated wood may be banned. Check any customs or environmental rules before shipping.

By considering these factors – load, mode, and compliance – shippers can choose the right dunnage materials. Good planning ensures minimal damage and maximizes safety for both goods and handlers.

FAQ

Q: What is dunnage, and why is it important in shipping?
A: Dunnage is any material used to support and protect goods during transit. It prevents cargo from shifting and absorbs shocks, which significantly reduces damage.

Q: What does "dunnage" mean in shipping?
A: It simply refers to the protective filler inside a load. Shipping dunnage can be wood blocks, air pillows, foam, etc. – anything that fills space and shields cargo from movement.

Q: What is the difference between dunnage and packaging?
A: Packaging is the box, crate, or pallet that holds the product. Dunnage is the filler inside that packaging. For example, a crate is packaging, while the wood blocks or bubble wrap inside it are dunnage.

Q: How does flatbed dunnage work?
A: Flatbed dunnage involves wood blocks (or metal stands) placed under cargo on an open trailer. These lift the load slightly off the trailer deck so that forklifts or cranes can move it, and keep the load from contacting the floor. This spacing prevents heavy items from sliding on the open deck.

Q: What is plastic dunnage?
A: Plastic dunnage includes products like plastic pallets or inflatable dunnage bags. It is durable and often reusable. For instance, a vinyl dunnage bag placed between pallets can be inflated to tightly wedge them in place, preventing shifting during transport.

Q: Does DR Trans provide dunnage materials?
A: DR Trans does not sell dunnage products. We are a freight and logistics provider. However, our experts help customers solve shipping problems by designing shipments with proper bracing and padding. We coordinate with carriers to ensure that loads are secured with the correct packing strategy, effectively solving many shipping damage issues.

Conclusion

Dunnage may seem like a simple packing material, but it is a powerful solution for preventing shipping damage. Dunnage refers to the range of materials – wooden beams, airbags, bubble wrap, and more – used to brace cargo. When properly selected and placed, dunnage keeps goods stationary and cushioned throughout transit. This not only avoids costly damage but also streamlines handling and protects equipment and workers.

At DR Trans, our mission is to provide reliable international shipping. We work with clients to implement best practices for cargo security. Although DR Trans doesn’t supply dunnage itself, our expertise ensures every shipment is packed with the right protective materials. By advising on proper dunnage selection and load planning, DR Trans helps businesses ship globally with confidence, knowing their cargo is well-protected against shocks and shifts.