Polystyrene box with lid: sizes and use
A polystyrene box with lid is the standard solution for cooled shipping of food and medicines. A polystyrene box from expanded foam insulates well, is lightweight and comes with a matching lid included. The size you choose determines how much you can fit in one box and how many boxes fit on a pallet. In this article we compare the most important sizes and explain what to look out for.
One box, three names
A polystyrene box with lid is also called foam box with lid or insulated box with lid in practice. It is always the same: expanded polystyrene, a white, lightweight plastic that consists of approximately 98% air. Polystyrene is the old brand name. Our polystyrene boxes with lids come from our own production since 1972 and are available immediately from stock. The lid comes with the box, so you order everything at once. Loose lids are only available on request.
What determines the right size polystyrene box?
Don't start with the outside dimensions, start with what needs to go inside. Measure the product you are shipping and add space for gel packs. The inside dimension is more important than the outside dimension, as the wall of a polystyrene box is thick. For a 12-liter box with 20 mm wall thickness, 400 x 300 x 155 mm on the outside leaves 365 x 260 x 125 mm on the inside.
Also consider the volume you are shipping. A box that is half empty lets air in and cools poorly. A box that is too full leaves no room for coolant. Rather choose one size smaller and use an extra gel pack than a box that is too large.
Sizes and wall thickness of our polystyrene boxes with lid
The table below shows a selection from the assortment. All sizes are available with lid and are delivered per pallet. The complete list with all variants can be found at our polystyrene boxes.
| Contents | Outside dimensions (mm) | Inside dimensions (mm) | Wall thickness | Per pallet |
|---|---|---|---|---|
| 5 liters | 300 x 200 x 155 | 270 x 170 x 120 | 15 mm | 360 pcs |
| 12 liters | 400 x 300 x 155 | 365 x 260 x 125 | 20 mm | 160 pcs |
| 19 liters | 500 x 300 x 210 | 460 x 260 x 165 | 20 mm | 96 pcs |
| 25 liters | 600 x 400 x 155 | 540 x 340 x 110 | 30 mm | 90 pcs |
| 34 liters | 600 x 400 x 205 | 540 x 340 x 165 | 30 mm | 60 pcs |
| 30 liters | 600 x 400 x 300 | 500 x 300 x 200 | 50 mm | 35 pcs |
| 45 liters | 600 x 400 x 400 | 500 x 300 x 300 | 50 mm | 25 pcs |
Four sizes in practice
The 5-liter polystyrene box is the compact size for small shipments. It measures 300 x 200 x 155 mm on the outside, has a wall of 15 mm and comes with and without drain holes. If you need more insulation in the same footprint, look at the 4.7 liter size of 300 x 200 x 200 mm with a 30 mm wall. It comes without drain holes and fits 200 pieces on a pallet.
The 20-liter polystyrene box measures 500 x 400 x 160 mm on the outside and 460 x 360 x 120 mm on the inside. The wall is 20 mm thick and 90 pieces fit on a full pallet. It is a spacious, flat box for medium-sized shipments.
The 400x300x300 polystyrene box has a capacity of 17.5 liters, inside dimensions of 330 x 230 x 230 mm and a 35 mm wall. 70 pieces fit on a pallet. The box has the same bottom as the 10-liter box of 400 x 300 x 200 mm, which also has a 35 mm wall and fits 100 pieces on a pallet. The stacking pattern remains the same, the box is just 10 cm taller. This is convenient for products that need to stand upright.
The 600x400x300 polystyrene box has a capacity of 30 liters and a 50 mm wall. The inside dimensions are 500 x 300 x 200 mm and 35 pieces fit on a pallet. The 600 x 400 mm bottom is a full euro size. If you want even more volume with the same wall, there is the 600 x 400 x 400 mm box with 45 liters, of which 25 pieces fit on a pallet.
Thin or thick wall?
The thicker the wall, the longer the contents stay cold. On the other hand, the outside dimensions become larger and fewer boxes fit on a pallet. For daily delivery within the UK, a thinner wall is often sufficient. For longer routes or hot summer days you choose a thicker wall. How long a box stays cold in practice depends on the outside temperature, the amount of coolant and how often the box is opened. Read more about this in our article how long does a polystyrene box stay cold.
With or without drain holes
Some sizes are available with and without drain holes. Boxes with drain holes drain melting water and are often used for fresh fish on ice. Boxes without drain holes keep moisture inside. View both versions at polystyrene boxes with drain holes and polystyrene boxes without drain holes.
Gel packs in your polystyrene box
A polystyrene box keeps cold in, but doesn't make it itself. For cooled or frozen shipping you need coolant. This can be gel packs or hard cooling accumulators. Place gel packs on top of the product, because cold air sinks down and cools the contents evenly. Fill the box as tightly as possible so there is as little air as possible left.
Polystyrene or another cool box
Polystyrene is not the best choice for every shipment. If you want a box that often comes back and is reused, then EPP is an option. If you prefer to ship without polystyrene, there are cardboard alternatives. You'll find a comparison in our article choose polystyrene or EPP. An overview of all cool boxes can be found at cool boxes.
Is the lid included?
Yes, a polystyrene box with lid is delivered including a matching lid. This is also stated with each product. A loose lid is only available on request.
Which size polystyrene box do I choose for a medicine shipment?
Choose the size that fits your product with gel packs exactly. For small shipments, a 5 or 12 liter box is common. The correct thickness depends on the shipping time and the temperature you need to maintain.
Can I order polystyrene boxes in large quantities?
Yes, the boxes are delivered per pallet. The number per pallet is listed in the table and with each product.
Buy polystyrene box with lid
Do you know which size you need? Then check out all polystyrene boxes from our own production, available immediately from stock. If you're unsure between two sizes, get in touch. We're happy to think it through with you.
