In clinical orthotics, orthotic insoles are a frontline tool for treating foot dysfunction, redistributing pressure, and improving overall biomechanics. The success of these insoles depends not just on clinical assessment and design, but also on material selection. One material consistently chosen by podiatrists, orthotists, and orthotic technicians is EVA foam.

Known for its flexibility, cushioning properties, and ease of customisation, EVA foam has become a workhorse in orthotic manufacturing. EVA provides the flexibility and performance that doctors need for diabetic foot care, sports injuries, and general muscle issues.

What Is EVA Foam?

EVA foam stands for Ethylene-Vinyl Acetate, a closed-cell copolymer that combines softness with structural integrity. Its unique cellular structure allows for various densities and thicknesses, making it ideal for constructing layers within orthotic insoles.

The material is resilient under repeated stress, making it a suitable choice for both temporary and long-term use. EVA comes in soft (20–30 Shore A) to high-density (up to 70 Shore A) grades. This lets clinicians customise orthotics based on the patient's condition, weight, and activity level. Its shock-absorbing and thermoformable qualities are critical in providing both comfort and function.

Key Properties of EVA Foam for Orthotic Use

There are several reasons EVA is so widely adopted in orthotics. The following characteristics are particularly important for clinical effectiveness:

  • Wide Density Range: Suitable for everything from cushioning top covers to weight-bearing bases.
  • Thermoplastic: Can be heat-moulded for custom fit and contouring.
  • Shock Absorbing: Helps manage impact-related foot pain and joint stress.
  • Lightweight: Does not contribute to shoe bulk or user fatigue.
  • Moisture-Resistant: Closed-cell structure resists sweat, bacteria, and odour.
  • Easy to Modify: Easily shaped, ground, or bonded using standard orthotic tools.

These benefits allow EVA foam to meet both the functional demands of the foot and the practical needs of busy orthotic clinics.

The Role of EVA Foam in Orthotic Insole Construction

Whether creating pre-formed insoles or bespoke orthotic devices, EVA foam is incredibly versatile. It's commonly used in both base and top layers, as well as in functional additions like heel cups, medial arch fills, and metatarsal pads.

For clinics offering chairside or lab-based orthotic fabrication, EVA foam allows rapid turnarounds without compromising on quality. It can be worked using standard heat guns, vacuum formers, and CNC milling systems.

CastingFoam Box

Step-by-Step: How EVA Foam Orthotic Insoles Are Made

The production of orthotic insoles using EVA foam typically follows a structured process to ensure both biomechanical precision and comfort. Here's a breakdown of key steps:

  1. Assessment and Casting: The process starts with a complete biomechanical assessment. Then, we take a 3D scan, foam box impression, or plaster cast of the foot.
  2. Material Selection: We choose EVA sheets or CAD-CAM blocks based on clinical goals. Denser foams provide structural support, while softer foams offer cushioning.
  3. Shaping: In labs, EVA blocks are shaped using CNC milling. For manual builds, sheets are cut and layered to match the required contour and correction.
  4. Heat Moulding: The foam is heated and vacuum-moulded over a positive cast or directly on the foot for a semi-bespoke fit.
  5. Customisation: Wedges, cut-outs, and top covers are added. EVA takes well to grinding and fine-tuning to ensure perfect fit and function.
  6. Finishing: Final quality checks are completed before fitting. Insoles can be trimmed to fit different shoe styles and patient preferences.

This adaptable process allows for a high degree of personalisation—particularly valuable when treating complex foot pathologies or high-risk patients.

Applications of EVA Foam in Clinical Practice

Across the podiatry and orthotics field, EVA foam is used to manage a range of conditions, including:

  • Plantar fasciitis: Offloading pressure and cushioning heel strike.
  • Metatarsalgia: Relief zones and pressure redistribution using met domes or apertures.
  • Diabetic foot care: Multi-layer EVA constructions for shear reduction and ulcer prevention.
  • Paediatrics: Lightweight, adaptable EVA orthoses for growing feet.
  • Post-surgical rehabilitation: Temporary orthotics that support healing and gait retraining.
  • Sports biomechanics: EVA’s responsive nature makes it excellent for shock control in running and field sports.

Its adaptability means EVA foam can serve both as a diagnostic aid (trial orthotics) and a long-term solution, depending on the patient’s condition and treatment plan.

Custom vs Prefabricated EVA Foam Orthotic Insoles

Prefabricated EVA orthotic insoles offer general support and comfort for mild symptoms or preventative use. They're often used as first-line interventions in busy clinics. However, for patients with complex biomechanical issues or ongoing pain, custom EVA orthotics are recommended.

Advantages of custom EVA orthoses include:

  • Tailored fit based on foot morphology.
  • Precision correction of structural deviations.
  • Customised pressure relief and shock absorption zones.
  • Ability to integrate into a broader orthotic management plan.

Prefab insoles can work well for everyday use. However, custom devices offer better long-term results in clinical care.

Maintaining EVA Orthotic Insoles

Although EVA foam is low-maintenance, advising patients on care will prolong device lifespan and performance. Best practices include:

  • Daily airing: Remove insoles from footwear to prevent moisture build-up.
  • Cleaning: Wipe down with a damp cloth and mild soap—never submerge or tumble dry.
  • Monitoring wear: Check for signs of compression, particularly in high-pressure zones like the heel or ball of foot.
  • Review appointments: Schedule periodic reviews to reassess alignment and function, especially in children or progressive conditions.

Routine checks and cleaning ensure EVA foam orthotic insoles continue to deliver reliable support and hygiene over time.

Addressing Misconceptions Around EVA Foam and Orthotic Insoles

It’s common for patients—and even some newer clinicians—to assume that all insoles are created equal. Addressing these misconceptions helps ensure better compliance and outcomes:

  • “Soft equals supportive” – Not always. Overly soft insoles can lack the structure needed for correction. EVA comes in precise densities to balance comfort with control.
  • “Custom insoles aren’t necessary” – Prefabs may be helpful, but custom orthotics with EVA foam allow for nuanced adjustments based on pathology, gait, and footwear.
  • “They fit any shoe” – EVA insoles can be trimmed, but the effectiveness also depends on the shoe’s design and fit.

Educating patients on the benefits of EVA and the rationale for clinical decisions can greatly improve satisfaction and adherence.

Conclusion: Why EVA Foam Remains a Go-To for Orthotic Insoles

For podiatrists, orthotists, and orthotic technicians, EVA foam represents the ideal combination of functionality, flexibility, and performance. It offers a responsive, modifiable platform that integrates seamlessly into both traditional and digital fabrication techniques. Most importantly, it helps deliver meaningful improvements in patient mobility, comfort, and foot health.

From assessment to final fit, EVA foam allows you to meet clinical objectives efficiently and confidently. Whether you’re refining a complex orthotic design or supplying a basic support insole, EVA remains one of the most reliable materials in your toolkit.

For further information on working with our EVA, visit our guide: EVA Sheets - All you Need to Know

To view Algeos EVA range: EVA Foam Sheeting