Polyethylene foam — or simply foam — is the most underrated protective packaging material. Everyone knows bubble wrap, but foam does something bubbles can't: protect flat surfaces without leaving marks, separate stacked items without them touching, and cushion impacts without adding significant thickness or weight.
If you ship products with delicate surfaces (lacquered wood, stainless steel, glass, electronics), foam should be your first choice. In this guide, we'll explain the types available, what thickness to choose, and how to combine it with other materials.
What is polyethylene foam?
It's a closed-cell foam made from expanded polyethylene. "Closed-cell" means the air cells are not connected — this gives it three key properties for packaging: it doesn't absorb water (waterproof), it doesn't deform easily under pressure, and it regains its shape after an impact.
Unlike polystyrene (the white crumbly styrofoam), polyethylene foam is flexible, doesn't shed particles, and doesn't scratch surfaces. That's why it's the preferred material for protecting electronics, optical instruments, lacquered furniture, and any product where a scratch is unacceptable.
Available formats
| Format | Description | Primary use |
|---|---|---|
| Sheets | Flat sheets cut to size | Separating stacked product layers, lining box interiors |
| Rolls | Continuous foam on a roll, cut with a utility knife | Wrapping large surfaces, continuous protection on production lines |
| Profiles and foam corner protectors | L- or U-shaped pieces for corners | Protecting furniture edges, frames, metal profiles |
What thickness do you need?
The thickness of the foam determines how much cushioning it offers. You don't always need the thickest — often 2 mm is enough.
| Thickness | Protection | When to use it |
|---|---|---|
| 1-2 mm | Surface protection — prevents scratches and marks | Separating stacked plates, protecting screens, wrapping lacquered furniture |
| 3-5 mm | Light cushioning — absorbs vibrations | Electronics, instruments, glassware, industrial parts |
| 10-20 mm | Strong cushioning — absorbs direct impacts | Machinery, heavy equipment, high-value objects |
Practical rule: if you only need two surfaces not to touch (plates, trays, wooden boards), 2 mm is sufficient. If the object needs to absorb an impact during transit, go up to 5 mm or more.
Foam vs. bubble wrap: when to use each
This is the most common question. The short answer: foam protects surfaces, bubbles protect against impacts.
| Criterion | Polyethylene foam | Bubble wrap |
|---|---|---|
| Scratch protection | Excellent — smooth, soft surface | Medium — bubbles can leave marks on lacquered surfaces |
| Impact cushioning | Good (depends on thickness) | Excellent — each bubble absorbs impact |
| Separating stacked items | Ideal — cut to size, lies flat | Impractical — bubbles cause items to shift |
| Wrapping irregular shapes | Difficult — foam doesn't conform to curves | Ideal — bubbles fold around any shape |
| Cost | Slightly more expensive per m² | More economical per m² |
In many professional shipments, the perfect combination is: foam in direct contact with the product (to prevent scratches) + bubble wrap wrapped around the outside (to absorb impacts). If you want to delve deeper into bubble wrap, we have a guide on types, uses, and prices of bubble wrap.
Real applications: where foam is used
E-commerce and shipping
Separating products inside a shipping box so they don't collide. Lining the inside of the box to create a cushioned "chamber." Wrapping consumer electronics (laptops, tablets, cameras) before bubble wrapping.
Moving
Protecting wooden furniture surfaces during transport. Wrapping mirrors and glass (foam + corner protectors on corners + reinforced flat box). Separating stacked plates and platters (a 2 mm foam sheet between each plate). If you're planning a complete move, check out our moving packs.
Industry and B2B
Protection of machined parts during storage and transport. Custom box interior lining for high-value products. Separators between product layers on pallets.
Is polyethylene foam recyclable?
Yes, expanded polyethylene is recyclable (LDPE 4 code, yellow bin). It's also reusable — if not damaged, you can use it many times. Unlike polystyrene, it doesn't crumble or contaminate with microparticles. If you're looking for even more eco-friendly alternatives, check out our guide to eco-friendly and sustainable packaging.
Frequently asked questions about polyethylene foam
What is polyethylene foam used for in packaging?
It is used to protect delicate surfaces from scratches (wood, glass, steel), separate stacked items without them touching, and cushion vibrations and impacts during transport. It is the preferred material for electronics, instruments, lacquered furniture, and any product where a scratch is unacceptable. At TeleCajas, it's available in rolls and sheets with 24-hour shipping.
What foam thickness do I need?
To separate surfaces without them touching (plates, trays, boards), 1-2 mm is sufficient. For light cushioning (electronics, glassware), 3-5 mm. For strong impact protection (machinery, heavy equipment), 10-20 mm. When in doubt, 5 mm is the versatile thickness.
What is the difference between foam and bubble wrap?
Foam protects surfaces (prevents scratches and marks) and separates stacked items. Bubble wrap absorbs impacts and wraps irregular shapes. In professional shipments, they are combined: foam touching the product + bubble wrap wrapped around the outside. For fragile items, consult the fragile product packaging guide.
Does polyethylene foam absorb water?
No. It is closed-cell, meaning it is waterproof. It does not absorb water or environmental moisture. This makes it ideal for maritime shipments, storage in humid areas, and protecting moisture-sensitive products.
Where can I buy polyethylene foam for packaging in Spain?
At TeleCajas, they have rolls and sheets of polyethylene foam in various thicknesses, available in the filling and protective material section. Shipping in 24-48 hours to all of Spain and Portugal, no minimum order. For industrial volumes, request a B2B quote.
For a complete overview of all available protective materials, consult our packaging materials guide.
