Which Cargo Fits Which Container? 20', 40', HC, Reefer, Open Top

Container types come down to four questions: how much space does the cargo take, how heavy is it, is there a height problem, and does it need temperature control? For most dry cargo the answer is a standard 20 ft or 40 ft container. Light but bulky cargo suits a 40 ft HC (high cube); cold-chain cargo needs a reefer; and cargo that cannot go through the doors, or is too tall, needs an open top or a flat rack. Below we explain each type and what it suits.

The dimensions and weights below are approximate. Internal measurements and maximum payload vary by manufacturer and shipping line; confirm current figures with the carrier or with us before loading.

Container types at a glance

| Type | In short | Typical use | |---|---|---| | 20 ft standard (20 DC) | About 33 m³ internal volume | Heavy, dense cargo: tiles, machine parts, bagged goods | | 40 ft standard (40 DC) | About 67 m³ internal volume | Medium-density, bulky palletised cargo | | 40 ft HC (high cube) | Same length and width as a 40 ft, about 30 cm taller | Light but bulky cargo: furniture, textiles, packaged consumer goods | | Reefer | Refrigerated, temperature-controlled | Food, pharmaceuticals and other temperature-sensitive goods | | Open top | Removable tarpaulin roof | Cargo loaded from above, or tall cargo | | Flat rack | No side walls; floor and end walls only | Very heavy, very wide or out-of-gauge cargo |

When to choose a 20 ft container

A 20 ft container makes sense when weight runs out before volume. If you try to fill a 40 ft with dense cargo you will exceed the weight limit, and the maximum gross weight is a regulatory and carrier rule with no "a little over" allowance. Tiles, metal products, chemical drums and bagged goods are typical candidates. It is also a sensible start for smaller shipments.

40 ft versus 40 ft HC

Both have the same length and width; the difference is height. An HC adds roughly 30 cm and raises the volume by about 13-14 percent. Three things decide whether to use it:

1. Bulky, light cargo benefits from the extra volume. Furniture, mattresses, textiles and packaging fall into this group.
2. Height limits (roads, bridges and underpasses) can make an HC a problem on the inland leg at destination. If you need delivery to the door, check the route with the carrier and the trucking company.
3. The quote may differ. The freight difference between HC and standard depends on the route and the season, so ask for both quotes.

Reefer containers: temperature-controlled shipping

A reefer has its own refrigeration unit and holds the temperature within a set range. It is used for food, fresh produce, pharmaceuticals and other sensitive cargo. Settle these points up front:

• The required temperature range, as specified by the cargo supplier. Do not guess it.
• Pre-cooling: The cargo must already be at the right temperature when loaded; reefer units are designed to maintain temperature, not to cool the cargo down.
• Ventilation and humidity settings, if any are needed.
• Power: The reefer has to be connected to power during transport and at the port or terminal. Ask the carrier and the terminal about the time limits and any related charges.
• Loading pattern: Cargo must be stowed so that air can circulate; filling every inch is not always right.

Reefer freight and surcharges are noticeably higher than for dry containers. Rather than quoting a fixed ratio, we recommend getting a quote.

Open top and flat rack: cargo that does not fit through the doors

An open top has a tarpaulin roof that can be removed, so cargo is lifted in from above by crane. It is used for machinery, long pipes or profiles, and cargo that exceeds the door height but fits within the body of the container.

A flat rack has no side walls and carries the load on its floor and end walls. It is used for very heavy cargo or cargo wider than a container. Two things matter for both:

• Out-of-gauge (OOG) cargo: If cargo protrudes over the top or sides, the quote and booking are assessed separately; the stowage plan, lashing and possible extra charges need to be known in advance.
• Equipment availability: These units are not available at every port at all times. Asking shortly before loading leads to delays.

Questions to ask before choosing

1. What are the total weight and volume of the cargo (gross, in its packed form)?
2. Is it pallets, bags, bulk or machinery? What are the pallet dimensions?
3. Which is the longest, tallest and widest piece?
4. Are there temperature, humidity or ventilation requirements?
5. If you need door delivery, are there height or weight restrictions at the destination?
6. Will loading and unloading go through the doors, or is a crane or forklift needed?

The answers usually point to one type. If you are weighing several, ask for separate quotes to compare costs side by side.

Common mistakes

• Calculating volume and forgetting weight. The weight limit can be reached before the volume is filled.
• Ignoring pallet dimensions. How pallets stack leaves less usable space than the total volume on paper suggests.
• Guessing the reefer temperature. Get the value in writing from the supplier.
• Leaving an open top or flat rack to the last day. Equipment availability is limited.
• Not asking about restrictions at the delivery point. The container may be fine at the port, but the truck route to the door can have height or weight limits.
• Choosing between LCL and FCL without looking at volume. If the cargo does not fill a container, compare the consolidated (LCL) option too.

Frequently asked questions

Which container type is the most common? For dry cargo, the 20 ft and 40 ft standard and the 40 ft HC are the three most common.

One 40 ft or two 20 ft? With heavy cargo you often need two 20 ft containers because of the weight limit; light cargo fits one 40 ft or 40 ft HC. Compare both in a quote for your route.

Can a reefer carry dry cargo? It is technically possible, but a reefer is expensive and not recommended for dry cargo.

Do port waiting charges vary by type? Free time and the daily charges after it depend on the carrier and the type. For the details, see our article on detention vs demurrage.

Checklist

• Gross weight and volume of the cargo are ready.
• The dimensions of the longest, widest and tallest piece are known.
• Temperature and ventilation needs are confirmed in writing (for reefers).
• If cargo is out of gauge, equipment and plan were notified in advance.
• Loading and discharge ports are pinned down with codes (port codes).
• Destination restrictions were checked for door delivery.

How we work at Medius

When we receive a quote request we look at the cargo, its dimensions and the route together, and where it helps we prepare separate quotes for two container types. To choose the right equipment for your cargo and get a current quote, contact us.