What is Dunnage? Definition, Types and More.

Shipping dunnage is the protective packaging or supporting material that secures and cushions cargo during storage or transit. It can take many forms, from bubble wrap and kraft paper to foam and even steel. By choosing the right type, third-party logistics (3PL) providers can reduce damage rates, cut replacement costs, and build a reputation that keeps clients coming back.

Read on to learn what dunnage is, when to use it, types of dunnage materials, and how reusable dunnage impacts sustainability.

What is dunnage?

In logistics, dunnage is any material used to protect cargo during storage or transit. The term is used in the rail and heavy freight industries, where it refers to materials like wood blocks that keep goods stable during travel. In shipping, however, it includes a broader range of materials, such as bubble wrap, kraft paper, foam, and steel.

Dunnage has three main functions: preventing cargo from shifting, absorbing vibrations and impacts that accumulate over long hauls, and creating moisture barriers for sensitive goods such as electronics or pharmaceuticals.

When to use dunnage

Dunnage is vital for many types of commercial shipments. As a general rule, 3PLs should use it for the following scenarios:

• Fragile or high-value items are involved: Products that can crack, deform, or shatter need dunnage that absorbs and distributes force before it reaches the item.
• Cargo is heavy or palletized: Large loads on flatbeds or in trailers need bracing to stay evenly distributed and prevent lateral movement when the vehicle makes a corner or brakes.
• Shipments are long-distance or multi-leg: Dunnage for long trips helps protect products from cumulative rough handling.
• Goods are prone to moisture damage: Humidity can compromise sensitive products like pharmaceuticals and electronics before anyone can spot visible damage. Dunnage can create a physical barrier that protects these goods from moisture.

9 types of dunnage materials

3PLs can choose from several types of shipping dunnage:

1. Bubble wrap: One of the most common dunnage packaging types, best for wrapping fragile items like electronics and glassware. It’s widely available and can be reused, although it’s not the most sustainable packaging option.
2. Kraft paper: Made from recycled paper, it’s slightly less protective than bubble wrap and is one of the least expensive options, eco-friendly, and great at blocking moisture.
3. Foam: Secure for irregularly shaped or fragile items, commonly used for electronics and precision instruments, and is usually cut or molded to fit the product.
4. Air pillows: Inflatable plastic pouches that fill void space to keep items from shifting. They are lightweight and generate less waste by volume than loose-fill alternatives.
5. Packing peanuts: Loose-fill pellets that conform to the shape of the content. Most are made from Styrofoam, which is not eco-friendly, but biodegradable cornstarch variants are becoming more common.
6. Corrugated inserts: Layered cardboard dividers that separate items within a carton to prevent contact between units.
7. Wood: Used to distribute weight and create clearance for forklift access, ideal for heavy industrial cargo.
8. Solid plastics and steel: Rigid structural dunnage for heavy or high-value loads.
9. Custom options: Designed to protect specific dimensions, though they come with higher costs and lead times.

Reusable dunnage for sustainability

Single-use dunnage is convenient, but it adds up over time in packaging costs and waste, especially for high-volume operations. 3PLs should consider replacing single-use materials with reusable dunnage systems, such as steel racks and molded plastic trays. These dunnage types can lower shipping costs and help achieve sustainability goals.

Reusable dunnage works best in closed-loop supply chains, where the same carriers and routes make return logistics practical.

FAQs on dunnage in shipping

What is the difference between dunnage and void fill?

• While these terms are often used interchangeably, void fill is a specific function within the broader category of dunnage. It refers to materials used specifically to fill empty space in shipped parcels.
• Dunnage is the overarching term that also covers materials used for blocking and bracing heavy items.

How do dunnage bags work for freight?

• Dunnage bags are flexible, air-filled cushions placed in the voids between cargo to secure, stabilize, and protect goods. Selecting the right bag depends on the weight of the product, the size of the void, and the transportation mode.

How does proper dunnage packaging impact eCommerce profit margins?

• Although protective packaging is an upfront expense, failing to use the right dunnage is ultimately far costlier for your bottom line. The right dunnage reduces product damages, which translates to fewer costly refunds.