Overview of the Different Styles of Insulated Shipping Containers

Depending on your type of transport needs, there are two types of containers you can use, refrigerated (or mostly known as Reefers) or non-refrigerated (known as insulated).  We will dive into the differences of each so you have a good understanding of what will be best for you and your transport needs.

The refrigerated shipping containers are known in the industry as “Reefers”.  These containers are set to keep goods at a subzero temperature.  The best uses of this type of container is fresh foods, such as fruits and vegetables, as well as frozen foods.  When you are looking at the amount of fresh food at your local grocery store that is NOT in season, you may wonder where it comes from.  Since it is off season your local growers would not have these foods available to sell to the grocery stores.  Therefore, these items come from other parts of the country or parts of the world that were shipped in a reefer.

Bananas are a good example of this. They are harvested while still green and hard, kept in a cool shipping container and will ripen as they are transported.  By the time they reach the store, they are ready for consumption.  If the shipping containers are not refrigerated, the bananas, along with other produce items, would rot and become inedible by time they were brought to the store.

There are two types of refrigerated shipping containers, internal and external.  The internal containers have the electrical unit built into the storage unit itself.  This can be controlled on the outside, but it is affixed so that it is part of the container.  For example, if a container is 20 feet wide, only 18 feet of the inside is used for storage, the other 2 feet is the refrigeration unit. Because it is flush and is the standard 20’ size, it can be easily stacked with other 20’ storage containers during transport.

The external refrigerated system is not recommended for transport because the actual refrigeration unit is on the outside of the container, much like an “add-on”.  This unit needs to be supported underneath and is not an ideal design to use when transporting produce across the ocean.  This external system is best for a fixed storage container that would not be moved. So, a container 20 feet wide container would utilize all 20 feet for storage, and there would be 2 feet of the refrigeration unit protruding from the side of the container, technically making it 22 feet wide.

The alternative is the insulated container.  This type of container is not refrigerated, has no electrical cooling device attached on the inside or the outside. This style will keep the temperature of product regulated.  So regardless of the elements and temperature outside, the goods on the inside will not get too hot or too cold, they will not rot, decay, buckle or be affected by external factors.

There are several types of insulated containers:

  • Foam
  • Blankets
  • Insulated Panels
  • Eco-Friendly


Depending on your budget, spray foam is a great choice.  It is highly recommended over the other types of insulation.  The reason is because the spray foam will get inside every nook and cranny on the inside (or if sprayed on the outside and underneath) and gives you a seamless vapor barrier. This is great “piece of mind” to know your container is secure.

It is also the fastest method of insulation as well as the greatest R rating (the R rating is how well the insulating material can resist heat flow; the higher the number the greater the resistance).

Although it is the most expensive of the options, it is by far one of the best methods to choose for insulating your storage container.


This type of insulation is your standard classic rolled insulation that you would use in your attic.  It does require studs to be erected inside the storage container.  It is very effective at keeping the temperature maintained. The upside of this insulation is the cost.  It is quite reasonable and the installation is simple, therefore not a lot of time is needed to insulate your container. The downside is most blanket insulation is made from fiberglass, so you must use extra caution when installing it.

Insulted Panels

The friendliest type of insulation is the panel insulation.  This does require stud walls, however.  The panels come in different widths so you can add the studs and simply fit the panels between each gap. It is easy to install and very effective.  The only downside is that it is slightly more expensive than the blanket (roll) insulation.  The upside is that it is thinner than the blanket insulation therefore it allows you to keep the thickness to a minimum without sacrificing space.


When it comes to the eco-friendly types of insulation, there are a few to choose from: wool, cotton, or mud.

The wool insulation is exactly like the blanket insulation discussed above, yet instead of fiberglass, natural sheep wool is used instead. Surprisingly, this can be made for a fraction of the energy requirements used to make the synthetic type.

Similar to the wool, cotton insulation is made from recycled cotton clothes. Cotton is a natural renewable resource which can be grown quickly to replace what’s recycled.  However, this costs twice as much as the fiberglass insulation.

The next type of eco-friendly insulation is mud.  This is a choice only used in the dry-hot climates, which will keep the heat out.  This type of insulation is not recommended for transporting your container.  It is only recommended for those shipping containers that are being used as an insulated storage unit.

People in India have been using this mud method of insulation for centuries. In fact, there are entire homes in India made from mud.  With shipping containers, all sides plus the roof need to be covered.  To accomplish this, battens must be used which will allow the mud to stick to the container. Obviously, this is recommended only for areas where rainfall is scarce.

Depending on your overall need for an insulated shipping container, whether it is being transported or perhaps is fixed and used as storage only, there are many options available.