What sandwich panels are used in box van bodies?

compoform · 12 Aug 2026

Box van bodies are most commonly built using thermoplastic sandwich panels with glass-fibre-reinforced skins bonded to a lightweight core material, typically PP honeycomb or PET foam. These panels replace traditional steel and plywood because they deliver structural rigidity at a fraction of the weight, which directly increases payload capacity and, for electric vans, extends battery range. The sections below answer the most common specification questions van body builders ask when selecting panel materials.

Which panel materials are most commonly used in box van bodies?

The most widely used materials in box van body construction are thermoplastic composite sandwich panels, typically consisting of glass-fibre-reinforced polypropylene skins bonded to a PP honeycomb or PET foam core. These panels are used for side walls, roofs, and floors, replacing steel sheet and plywood in most modern van body builds because they are significantly lighter while maintaining the structural performance the application demands.

The shift away from steel and wood has accelerated in recent years, driven by two converging pressures. First, fleet operators are demanding lighter bodies to maximise payload within legal gross vehicle weight limits. Second, the rapid adoption of electric vans has made body weight a range argument as much as a payload argument. Every kilogram of structural dead weight in the body reduces the distance an electric van can travel on a single charge, and in 2026 this is a standard procurement question from EV fleet buyers evaluating van body composite panel applications.

For side walls, cross-ply glass-fibre laminates over a PP foam core are the standard choice. For floors, where compressive and bending loads are higher, PP honeycomb cores with multi-ply skins deliver the load-bearing performance needed without adding unnecessary mass. Roofs typically use lighter-weight foam-core panels where structural demands are lower.

What core materials are used inside sandwich panels for van bodies?

The two core materials used in thermoplastic sandwich panels for van body applications are PP honeycomb and PET foam (also referred to as oriented PP foam in some configurations). PP honeycomb cores are preferred for floor panels where high compressive strength and bending stiffness are needed. PET foam cores are used in wall and roof panels where weight reduction is the priority and load demands are lower.

PP honeycomb cores consist of a tubular cell structure that distributes load efficiently across the panel face. The geometry of the honeycomb means the core resists crushing under point loads, which is relevant for van floors that must withstand pallet jacks, fork tines, and concentrated foot traffic. PP foam cores, available in a range of densities, allow designers to tune the stiffness-to-weight ratio for each panel position in the body.

It is worth noting what core materials are not used in thermoplastic van body panels. Balsa wood, aluminium honeycomb, mineral wool, polyurethane foam, and corrugated cores belong to different product families and different industries. Thermoplastic sandwich panels for commercial vehicles are built around PP- and PET-based cores because these materials are compatible with thermoplastic processing, are fully recyclable, and perform consistently across the temperature range a van body experiences in European operating conditions.

What are the skin materials on composite sandwich panels?

The skins on composite sandwich panels for van bodies are typically glass-fibre-reinforced polypropylene laminates, with the fibre content and ply orientation selected to match the load direction and surface requirements of each panel position. Skins can carry a white PET-film surface for interior wall panels or a black anti-skid finish for floor panels.

Skin architecture matters more than skin thickness alone. A cross-ply laminate, where fibres run at 0° and 90° in alternating layers, distributes mechanical properties equally in both directions. This makes the panel orientation-independent during installation, which simplifies assembly for van body builders working at volume. A multi-ply unidirectional laminate concentrates strength along a single axis, which is useful for floor panels where the dominant load direction is predictable.

Surface finish is a functional specification, not just an aesthetic one. White PET-film surfaces on wall panels provide a finished interior surface that requires no additional lining, removing a production step. The anti-skid surface on floor panels is integral to the composite skin rather than a coating applied afterwards, which means it does not wear off or delaminate under repeated loading and washing.

How do sandwich panels compare to steel and aluminium in box van construction?

Thermoplastic sandwich panels are significantly lighter than steel and moderately lighter than aluminium at equivalent structural performance, and they do not corrode. For van body builders, the practical result is a higher net payload, lower fuel or energy consumption, and a body structure that does not require repainting or anti-corrosion treatment over its service life.

Steel side walls and floors add dead weight that comes directly out of the van’s legal payload. Replacing steel with composite sandwich panels can recover meaningful payload capacity per vehicle, and across a fleet this compounds into a measurable commercial advantage. For electric vans, the benefit extends further: a lighter body structure reduces the energy demand per kilometre, which extends range per charge. This is not a secondary consideration in 2026, fleet operators specifying new electric van bodies are asking body builders directly about panel weight as part of the procurement process.

Aluminium is lighter than steel but still heavier than a well-specified composite panel, and it requires joining and sealing at every edge to prevent moisture ingress. Composite sandwich panels are manufactured as single-piece sections up to very large dimensions, which reduces the number of joints in the body and the associated risk of water infiltration over time.

On lifespan, thermoplastic composite floors outperform plywood by a substantial margin. Industry experience from heavy transport applications shows composite floors lasting 12 or more years in service, compared to 3 to 5 years for plywood before replacement is needed. Over a 15-year vehicle life, a composite floor eliminates two or three plywood replacement cycles. When you factor in panel cost, installation labour, and vehicle downtime for each replacement, the composite option is cheaper per year of service even at a higher unit price.

What panel dimensions and formats are available for van body builds?

Thermoplastic sandwich panels for van body construction are available in custom dimensions cut to the exact specification of the body design, with maximum sheet sizes reaching 13,500mm in length and 2,950mm in width. Thickness ranges from around 11mm for lightweight wall applications up to 30mm or more for structural floor panels, depending on the load requirements of the build.

The ability to produce panels in large single-piece formats is relevant for van body builders because it reduces the number of joints in the finished structure. A side wall produced as a single panel rather than multiple joined sections is faster to assemble, structurally more consistent, and easier to seal against moisture. For floor panels, large-format production means the floor can often be laid in one or two pieces rather than multiple sheets, which simplifies installation and reduces the risk of panel edge damage at joints.

Panel thickness and core density are specified together to achieve the required stiffness and load rating for each position in the body. A floor panel carrying pallet loads needs a different specification than a roof panel carrying only its own weight and minor wind loads. Custom specification means you are not paying for more panel than the application requires, which keeps the body weight as low as possible.

Are thermoplastic sandwich panels recyclable at end of life?

Yes. Thermoplastic sandwich panels are fully recyclable at end of life because both the PP-based core and the glass-fibre-reinforced thermoplastic skins can be reprocessed. This distinguishes them from thermoset composites, which cannot be melted and reformed, and from mixed-material assemblies that require separation before recycling.

For European van body builders and fleet operators, recyclability is increasingly a compliance requirement rather than a preference. The EU End-of-Life Vehicles (ELV) Directive sets targets for the recovery and recycling of materials from vehicles at the end of their service life. Specifying thermoplastic composite panels supports compliance with these requirements and simplifies end-of-life processing compared to bodies built with non-recyclable materials.

The Corporate Sustainability Reporting Directive (CSRD) is also driving procurement decisions in 2026. Larger fleet operators and logistics companies subject to CSRD reporting are asking their suppliers, including van body builders, to document the recyclability and environmental profile of the materials used in their products. Thermoplastic sandwich panels provide a straightforward answer to that question.

How Compoform Helps with Sandwich Panels for Box Van Bodies

We design and manufacture thermoplastic sandwich panels specifically for commercial vehicle applications, including box van bodies, truck bodies, and trailers. Every panel we produce is made to order, which means you specify the core material, core thickness, skin architecture, surface finish, and panel dimensions for your exact build, and we manufacture to that specification.

Custom dimensions up to 13,500mm x 2,950mm x 150mm, produced on a 72-metre double belt press at our facilities in the Netherlands
PP honeycomb cores for floor panels requiring high compressive and bending performance, and PET foam cores in multiple density grades for wall and roof panels
Glass-fibre-reinforced PP skins in cross-ply and multi-ply configurations, with white PET-film or anti-skid surface finishes depending on the panel position
Self-supporting floor panels that eliminate the need for an aluminium subframe, removing a production step and reducing total body weight further
Edge sealing and edge bending to protect the core from moisture ingress, relevant for van floors that are washed down regularly in service
100% European manufacture, with consistent lead times and post-sales support for ongoing production runs

Before production, we review your body design, assess the load requirements for each panel position, and recommend the configuration that meets your structural and weight targets. If there are integration challenges in your assembly process, we identify them at the design stage rather than after panels have been delivered. To discuss your van body panel specification with our engineering team, contact us directly.