The short answer to EVA vs EPP foam: EVA when the foam has to be soft in the hand, follow a curve or seal. EPP when it has to carry a load, hold a dimension, work above 65 °C, or be recycled. EVA compresses under a fingertip at 20–30 kPa; EPP reaches 325 kPa.
DBM molds both in-house. Figures are typical ranges, not guaranteed limits: your part depends on geometry, wall thickness and as-molded density. We confirm final numbers in writing before tooling.
Pick either one up and the difference shows before any datasheet. EVA gives under a thumb at Shore OO 40–46. EPP does not move; it deforms only under a real load, then recovers. They compete in one place: the interface between a payload and its container.
The EVA and EPP columns of the thirteen-material dataset behind our comparison tool.
| Property | EVA | EPP | What the gap means for your part |
|---|---|---|---|
| Molded density (kg/m³) | 30–50 | 20–66 | EVA sits in a narrow band in the middle. EPP starts lighter and keeps going to 66 kg/m³, which is where load-bearing and structural parts live. |
| Compression stress at 10% strain (kPa) | 20–30 | 50–325 | The largest gap on this page. EVA is between two and eleven times softer, which is the whole point of choosing it, and the reason it cannot be a load-bearing part. |
| Energy return / rebound (%) | 37 | 30 | Close, with EVA slightly ahead: 37% against 30%. Rebound is not the row that separates these two materials; what separates them is the force at which it happens. EVA springs back from a hand squeeze, EPP from an impact. |
| Long-term service temperature (°C) | 65 | 100 | EVA is the lowest-temperature material we mold. A closed vehicle interior or a warm assembly line can cross 65 °C, and above it EVA softens and takes a set. |
| Minimum service temperature (°C) | −40 | −40 | Level as a service limit. The difference is behaviour: at −40 °C EVA is still soft and pliable while EPP is intact but rigid, which is why cold-weather grips and gaskets still go to EVA. |
| Thermal conductivity, W/(m·K) | 0.04 | 0.036–0.042 | Practically identical. Neither material is chosen for insulation when EPS or Beaded EPE is available, and neither is a reason to reject the other. |
| Feel and rigidity | Very soft: visibly compresses under a fingertip | Semi-rigid: cushions under load, not under a finger | Press both with a thumb. Only one of them moves, and that single test predicts most of the decision. |
| Flame behaviour | No flame rating held; can be modified to reach one | GB 8410 ≤70–90 mm/min | EPP is published with a horizontal burn rate against the automotive interior method, and flame-retardant grades exist across the density range. EVA carries no rating as we mold it. |
| Chemical resistance | Resists weak acid and alkali; ester groups weak against strong oxidisers and aromatics | Polyolefin base: good with acid, alkali, alcohols; not aromatics or chlorinated solvents | EPP is the safer choice anywhere near solvents, fuels or line-cleaning agents. EVA is comfortable with water, mild detergents and skin contact. |
| Weather resistance | Ester groups hydrolyse under UV and damp heat; worse at higher VA content | PP tertiary hydrogen triggers photo-oxidation; chalks outdoors within months without additives | Neither is an outdoor material as supplied. Both can be lifted with UV additives, and both should be if the part lives outside. |
| End of life | Cross-linked: cannot be melt-reprocessed, hard to recycle | Thermoplastic, re-pelletisable, no cross-linking | The one difference that is structural rather than numerical. Cross-linking is what gives EVA its elasticity, and it is also what closes the recycling route. |
Same dataset, all thirteen materials
EVA reaches 39 kPa at 25% strain in EV30 and 50 kPa in EV50. EPP needs 80–110 kPa at its softest grade and 315–395 kPa at its stiffest. A hand can compress EVA and cannot compress EPP. The mechanism is elongation: EVA stretches 205–243% before breaking, EPP 15% or more. EVA can be wrapped around a radius; EPP has to be molded to shape.
A part that holds a payload has to resist stress without deflecting into it. EPP does that at 50–325 kPa at 10% strain; EVA at 20–30 kPa. Put a five-kilogram assembly into an EVA nest and the nest closes around it; a 40–50 kg/m³ EPP nest holds it in place. EVA survives cycling well, so this is a stiffness limit, not a durability one.
EVA has a low heat ceiling: 65 °C maximum service, crossed in a parked vehicle interior or a summer container. Above it EVA softens and takes a permanent set. EPP runs continuously to 100 °C, so anything thermally uncertain defaults to EPP. Both are serviceable to −40 °C, but there EVA is still pliable while EPP is rigid.
Cross-linked EVA is closed-cell, water absorption below 1%, cells around 0.4 mm, fine enough for a smooth sealing face. Compression set is 4% in EV30 and 2% in EV50 after a 50% squeeze: the standard recipe for gaskets, lid seals and vibration pads. EVA is also gentler on a finished surface, with no bead boundaries to imprint and no shedding. Over an EPP body, an EVA facing is a common hybrid.
EVA foam is cross-linked. The cross-links give it its elasticity and stop it being melted and re-pelletised, so scrap and end-of-life parts have limited routes. EPP has no cross-linking: grind it, re-pelletise it, re-expand it. Under a packaging-waste or recycled-content obligation this is often the deciding row, and no grade change fixes it.
EPP burn rates are published against GB 8410, the automotive interior horizontal burn method: ≤70 mm/min at 54–66 kg/m³, ≤80 at 40–50 kg/m³, ≤90 at 27–33 kg/m³. Flame-retardant grades run across the density range. EVA holds no rating, and reaching one means a filler load that changes the feel. A burn rate is not a vertical-burn classification. Tell us your standard and we will confirm what the grade holds.
Per kilogram the two are in the same class, so the cost driver is how much polymer ends up in the part and how it gets there. EVA is cut, skived or compression-formed from sheet stock: waste plus per-part labour. EPP is molded net to shape: a tooling cost, then very little per part. Low volume and simple shapes favour cut EVA; volume or non-prismatic geometry favours molded EPP.
Ten application families, the material we start from, and why.
| Application | Start from | Typical density | Why |
|---|---|---|---|
| Gaskets, lid seals and enclosure perimeters | EVA | 30–50 kg/m³ | Closed cells, water absorption under 1%, a soft compression curve and 2–4% compression set. Nothing else on our list seals as well. |
| Returnable dunnage and KLT inserts | EPP | 27–50 kg/m³ | The insert has to hold the payload in position for hundreds of trips. Stiffness and dimensional stability are the specification. |
| Footwear midsoles, insoles and sports padding | EVA | 30–50 kg/m³ | Soft under body weight, high elongation for a contoured last, and excellent recovery over daily cycling. |
| Automotive energy absorption | EPP | 40–66 kg/m³ | Cabin temperatures, a burn-rate specification, and a core that must still be intact after a low-speed event. |
| Tool, instrument and camera case inserts | EPP body with an EVA facing | 27–50 kg/m³ | The load path wants EPP; the face that touches a finished product wants EVA. A two-material insert is a normal job, not a special project. |
| Appliance and HVAC internals | EPP | 27–50 kg/m³ | Air paths run warm, assembly is automated, and parts must not shed into the machine. EVA has no thermal margin here. |
| Hand grips, kneeling mats, medical positioning pads | EVA | 30–50 kg/m³ | A person is pressing against it. Softness is the requirement, and EPP is simply the wrong hardness class. |
| Battery module trays and ESS packaging | EPP | 40–66 kg/m³ | Load-bearing, returnable, and normally required to hold a flame specification. Flame-retardant EPP grades exist for this. |
| Cold-store handling parts and winter outdoor grips | EVA | 30–50 kg/m³ | The one temperature case EVA wins: flexible to −40 °C where EPP stops at −40 °C. |
| Cold-chain shippers and insulated boxes | Neither (EPS or Beaded EPE) | 20–30 kg/m³ | A third material fits better. Insulation-led parts start from EPS, and flexible cold liners from Beaded EPE. |
Both are families of grades, and the grade decides the part more than the polymer. EVA figures are to ISO 7214:2012 with hardness to ISO 868:2003, EPP compression to ISO 844.
| Grade | Material | Density (kg/m³) | Key values | Where it belongs |
|---|---|---|---|---|
| EV30 | EVA | 30 | 39 kPa @25% · Shore OO 40 · elongation 205% | The softer grade. Conforming pads, gentle surface contact, light sealing faces and comfort layers. |
| EV50 | EVA | 50 | 50 kPa @25% · Shore OO 46 · elongation 243% | Firmer sealing and padding with better tear strength (2.880 kN/m) and the lowest compression set we publish. |
| 20–25 kg/m³ | EPP | 20–25 | 50–70 kPa @10% · tensile 420–560 kPa | Ultra-light cushioning, insulation and dunnage where weight is the constraint. |
| 27–33 kg/m³ | EPP | 27–33 | 70–100 kPa @10% · tensile 550–750 kPa | Protective packaging and lightweight parts with strong energy absorption. |
| 40–50 kg/m³ | EPP | 40–50 | 130–175 kPa @10% · tensile 800–1000 kPa | Structural cushioning: automotive, handling trays, heavier returnable packaging. |
| 54–66 kg/m³ | EPP | 54–66 | 255–325 kPa @10% · tensile 1050–1350 kPa | Structural and load-bearing parts. The stiffest grade in this comparison by a wide margin. |
EPP arrives as pre-expanded polypropylene beads, is blown into a vented aluminium cavity and fused with steam into a finished part with a molded skin, pockets and ribs. Cross-linked EVA is made as sheet or bun stock, then cut, skived, laminated or compression-formed.
Two consequences. Geometry: EPP holds a contoured nest with undercuts in one shot, an EVA part is built from cut layers or a flat blank. Tooling: EPP carries a tool cost before the first part exists and EVA does not, so volume decides the cheaper route.
If the pair above is not yours, one of these is.
| Comparison | The decision it settles |
|---|---|
| EPP vs EPS foam | Recovery against cost. Whether the part is struck once or many times, and whether insulation or reuse leads the specification. |
| EPP vs ETPU foam | Elastomer resilience at around 200 kg/m³ against all-round cushioning at 30. What the extra polymer mass actually buys. |
| EPP vs Beaded EPE foam | Rigidity and repeated impact against soft wrap, surface safety and service down to −70 °C. |
| EPP vs EPO foam | Where a PS/polyolefin composite bead at 16 kg/m³ is better value than either EPS or EPP. |
| All thirteen, ranked | Every material sorted on each of the seven properties that settle a spec. |
| EPE vs Beaded EPE foam | The same polyethylene shaped two ways: what the forming route costs and buys. |
| Cut vs molded foam | Which forming process the part needs: shape freedom and seams against tooling commitment. |
Hardness, and everything that follows from it. EVA is a soft cross-linked closed-cell foam that compresses under a fingertip at 20–30 kPa and stretches 205–243% before breaking. EPP is a semi-rigid molded bead foam that reaches 50–325 kPa depending on density grade and stretches about 15%. So EVA is chosen when the foam has to conform, seal or feel soft, and EPP when it has to carry a load and hold a dimension.
No. EPP is between two and eleven times stiffer in compression: 50–325 kPa at 10% strain against 20–30 kPa for EVA. EVA is stronger in tension and elongation, at 520–749 kPa tensile with 205–243% elongation against roughly 15% for EPP, which is why it can be stretched around curves. If the part has to support a payload, that is a compression question and EPP wins it.
EVA, marginally: it returns 37% of the energy it absorbs against 30% for EPP. The two are close enough that rebound percentage is not the row that separates them. What separates them is the force at which that rebound happens. EVA springs back from a hand squeeze, EPP springs back from an impact, and only EPP is stiff enough to hold a load while it does it.
EVA is rated to a recommended maximum service temperature of 65 °C, among the lowest of the materials we mold, and stays flexible down to about −40 °C. EPP runs continuously to 100 °C with short excursions higher, and is rated down to −40 °C. So EPP owns the heat case (engine bays, appliances, sealed containers), and EVA has the better cold margin.
EPP can. It is a single thermoplastic with no cross-linking, so it can be ground, re-pelletised and re-expanded, and a returnable EPP part is usually reused many times before it ever reaches that stage. Cross-linked EVA cannot be melt-reprocessed, because the cross-links that give it elasticity also prevent it from being melted back down. For programs with recycled-content or packaging-waste obligations this is often the deciding difference.
Yes, and it is a common answer when the requirement is a stiff nest with a soft face. The usual construction is a molded EPP body that carries the load and locates the payload, with a bonded EVA facing on the surfaces that touch a finished product. We mold and assemble both materials in-house and quote the result as a single part rather than as two.
You do not have to name a material. Tell us what the part touches, what it carries and how hot it gets. We come back with a material, a grade and a sample plan in 48 hours.