Insulating a sea container: inside or outside?
Shipping container insulation for transport is quickest on the inside, with a thermal container liner that shields the entire cargo space in one go, without installation work. Insulation boards or panels against the wall and ceiling are another way to insulate. Below you will read the difference between the inside and the outside.
Shipping container insulation on the inside: why it works in transport
A sea container without insulation is sensitive to external temperature swings. In summer it can reach 60 °C inside a container, and on winter routes there is frost.
Insulating a container on the inside means you place the insulation between the cargo and the steel wall. A sea container insulation liner does this with reflective, aluminum-laminated bubble foil. It limits the effect of solar radiation, heat and cold and can be installed without specialist tools. When handled with care, it is reusable.
For which cargo do you choose a container liner?
For cargo that cannot go straight into a refrigerated reefer but is temperature sensitive. Examples are wine, oil, chocolate, cosmetics and electronics, which are sensitive to heat or to frost on winter routes. A container liner is also used for food, fish, meat, pharmaceutical products and chemicals to limit temperature swings. If a fixed temperature window is required, that calls for a different solution.
Which container liner size fits?
| Container type | Liner size in cm |
|---|---|
| 20DV | 589 x 233 x 233 |
| 40DV | 1,200 x 233 x 233 |
| 40HC | 1,200 x 233 x 269 |
| 45HC | 1,335 x 233 x 269 |
Insulating a sea container on the outside: what is the difference?
If you want to insulate a sea container from the outside, you place insulation against the outer wall of the container. A container liner lies on the inside instead, between the cargo and the wall, and insulates the entire cargo space in one go.
Container insulation panels and other insulation boards are placed against the wall and the ceiling. The liner is quick to place, reusable and needs no installation work.
Container liner or fixed insulation: the comparison
| Item | Container liner | Fixed insulation or panels |
|---|---|---|
| Location of the insulation | Inside, between cargo and wall | Against wall and ceiling |
| Coverage of the cargo space | Entire cargo space in one go | Wall and ceiling |
How to place a container liner
Choose the size from the table above. The container liners come with an installation guide of 9 steps with photos, from unrolling on the container floor to zipping up the door cover.
Against condensation, and what a container liner does not do
Heat is not the only risk: moisture in the container causes condensation, mold and corrosion. A container liner helps reduce condensation, but it does not absorb moisture. For that you hang container desiccant bags from the eyes in the container. A bag of 1,200 grams absorbs up to 4 liters of moisture. You can read more about moisture damage in Condensation and heat in the container: liner and desiccant bags.
What a container liner does not do:
- It does not cool. It limits temperature swings, it does not adjust anything.
- It gives no guarantee on a temperature.
If the cargo must stay strictly refrigerated, a reefer is the right route. You can read how to weigh that in reefer or container liner: how to weigh the costs.
Frequently asked questions about shipping container insulation
Is it better to insulate a container on the inside or the outside for transport?
For transport you place a container liner on the inside. It insulates the entire cargo space in one go, is quick to place, needs no installation work and is reusable when handled with care.
Can I insulate a sea container from the outside with panels?
Sea container insulation is also done with insulation boards or panels against the wall and ceiling. The advantage of the liner is that it insulates the entire cargo space in one go, without installation work.
Does a container liner keep my cargo cold?
No. A container liner limits the effect of heat and cold, but it does not cool. If the cargo needs strict cooling, you choose a reefer.
Order directly
Do you want to insulate a container for your next shipment? See the range of sea container insulation with liners for 20DV, 40DV, 40HC and 45HC, available from stock. Do you ship single pallets instead of full containers? Then look at the insulated pallet covers.
You will find all names for this product in our glossary.
