Insulated shipping box: what does the term cover?
An insulated shipping box is a box that holds the temperature of its contents, but the term does not say what the box is made of. If you are looking for an insulated box for refrigerated shipping, you can choose from four kinds: an EPS box made of foam, a cardboard box with Isoliners, a honeycomb box and a foldable thermal box. Below you will find what each type is, so you know what to ask for.
Insulated box is a collective name
The term insulated box stands for several products. At Cooled Solutions, a manufacturer with our own production since 1972, we also call the EPS box itself an insulated foam box. Cardboard cooling boxes with insulation inside are called that as well.
An EPS box, or expanded polystyrene box, is made of expanded polystyrene, commonly called foam. The material is about 98% air and 2% polystyrene. That air is trapped in millions of closed cells, and so heat barely passes through. In the honeycomb box, hexagonal air chambers in the wall hold still air, the same principle as with foam.
The four kinds of insulated boxes side by side
The table lists the four types, with the data from our range.
| Type | Construction | Sizes (outside size) | After use |
|---|---|---|---|
| EPS box | One piece of foam, including a matching lid | From 4.7 to 173 liters, for example 400 x 300 x 200 mm | Reusable |
| Cardboard insulated box | Corrugated cardboard box with 2 Isoliners (paper insulation sheets) | S 250 x 250 x 250, M 300 x 300 x 300, L 355 x 355 x 355 mm | Paper recycling |
| Honeycomb insulated box | Insulation in the wall itself, honeycomb cardboard with corrugated cardboard | 300 x 300 x 300 mm, inside size 240 x 240 x 240 mm | Paper recycling |
| Thermal box | Foldable cardboard box with a separate insulated bag | Cardboard box of 300 x 200 x 200, 400 x 300 x 200 and 400 x 300 x 300 mm | Box: paper recycling. Insulated bag: plastic |
All four are meant for refrigerated shipping. For the cardboard insulated box with Isoliners, the insulation value is comparable to EPS. That is how it is stated with the product. We therefore make no statement about how many hours it stays cold: that depends on the size, the coolant and the outside temperature.
What sets each insulated box apart
- EPS box: supplied preformed. The 10 liter box of 400 x 300 x 200 mm is the best-selling size in daily refrigerated shipping.
- Cardboard insulated box: supplied flat, and the sheets are stocked flat. You assemble the box only when packing.
- Honeycomb box: the honeycomb structure makes the wall insulating and sturdy at the same time.
- Thermal box: a cardboard box with a separate insulated bag, supplied flat and foldable.
The difference between EPS and cardboard is covered in EPS boxes or honeycomb cooling boxes. Where a thermal box differs from an EPS box is explained in thermal box or EPS box.
What you can choose with an EPS insulated shipping box
If you choose insulated boxes made of EPS, they differ on four points. The first is the capacity, from 4.7 to 173 liters. The second is the wall thickness: the boxes in our range run from 15 mm to 60 mm for the largest box, and a thicker wall keeps the contents at temperature longer. For a 10 liter box with a 35 mm wall, our product data gives a cooling time of 24 to 48 hours, depending on the number of cooling elements you include. That time therefore applies to that box with that load, not to every insulated box.
The third choice is with or without drain holes. Drain holes carry off meltwater, for example with fish. Without drain holes, liquid stays in the box. The fourth is a cardboard master carton for extra protection during transport, which is available for several sizes. Every EPS box is supplied with a matching lid.
To keep things cold, use ice packs or cooling elements. Place them on top of the product and fill the box tightly, because air in the box works against you. How many you need is covered in Shipping ice packs: what determines the number?.
How to determine the right size of an insulated box is covered in choosing the right box size. More on the options in general is in choosing an insulated box for shipping.
For ready-made solutions, also see our cooling boxes and cold chain packaging.
Frequently asked questions about insulated boxes
Is an insulated box the same as an EPS box?
Sometimes yes, sometimes no. An EPS box is also called an insulated box, but cardboard insulated boxes exist too.
Is a cardboard insulated box as good as foam?
For the cardboard insulated box with Isoliners and the honeycomb box, the product sheet gives an insulation value comparable to EPS.
Does an insulated box always have a lid?
With an EPS box it does: it is supplied including a matching lid. Separate lids are only available on request.
Do you know which type you are looking for? See our insulated shipping box from our own production, available from stock right away, and contact us if you are unsure between two sizes.
You will find all names in our glossary.
