What is the best lightweight sandwich panel for a campervan build?

compoform · 09 Aug 2026

For a campervan build, thermoplastic sandwich panels with a PP foam or PP honeycomb core and glass-fibre-reinforced skins are the best lightweight option. They deliver a high strength-to-weight ratio, resist moisture and impact, and outlast plywood or aluminium sheet in mobile living environments. The sections below answer the most common technical questions builders ask before specifying panels.

Note: This article covers the broader sandwich panel market. Our range at Compoform is limited to PP honeycomb and PP foam cores, manufactured for commercial vehicle and related applications.

What materials are commonly used in campervan sandwich panels?

Campervan sandwich panels are built from three layers: two structural skins bonded to a lightweight core. The core material determines the panel’s weight and stiffness, while the skin material determines its surface durability and impact resistance. The most widely used core materials are PP foam, PP honeycomb, and XPS foam, with glass-fibre-reinforced thermoplastic or GRP skins on either face.

Core materials

PP foam (polypropylene foam): Available in a range of densities, typically 40 to 140 kg/m³. Lower densities reduce weight; higher densities improve compressive strength. Well suited to wall panels where insulation and rigidity both matter.
PP honeycomb: A tubular polypropylene structure that offers excellent bending stiffness relative to its weight. Commonly used in floor panels where point loads are higher.
XPS foam: Extruded polystyrene, widely used in budget builds for its thermal insulation, though it offers lower structural performance than PP-based cores.

Skin materials

Glass-fibre-reinforced thermoplastic (GFRT): The most common choice for structural campervan panels. Skins typically contain 66 to 67% glass fibre content, delivering high tensile strength and impact resistance.
GRP (glass-reinforced polyester): A thermoset alternative used in many production campervans and caravans. Durable but not recyclable at end of life.
Aluminium sheet: Sometimes used as a skin over foam cores in entry-level builds. Heavier than composite skins and prone to denting.

How does panel weight affect campervan performance and payload?

Panel weight directly affects how much gear, water, and equipment you can legally carry. In most European countries, a standard campervan conversion is limited to the vehicle’s gross vehicle weight rating (GVWR). Every kilogram saved in the body structure is a kilogram you can convert into usable payload — whether that is a larger water tank, a heavier battery bank, or additional equipment.

Beyond payload, weight affects fuel consumption and, increasingly, electric range. In 2026, a growing number of campervan conversions are built on electric van platforms. Lighter body structures extend battery range per charge, because the drivetrain carries less dead weight on every journey. Weight reduction in a campervan build is therefore both a payload argument and a range argument — and the two compound each other when the base vehicle is electric.

A composite sandwich panel wall section typically weighs significantly less than an equivalent plywood-and-insulation assembly. The structural skin and core work together, so you do not need to add a separate insulation layer behind the panel in many configurations. This reduces both weight and build complexity.

What’s the difference between thermoplastic and thermoset composite panels?

The core difference is how the resin system behaves under heat. Thermoplastic panels can be reheated and reshaped after manufacture; thermoset panels cure irreversibly during production and cannot be reformed. This distinction affects recyclability, impact behaviour, and how the panels respond to damage.

Thermoplastic composite panels, such as those with glass-fibre-PP skins, tend to absorb impact energy more effectively than thermoset equivalents. When a thermoset panel is struck hard, the resin matrix can crack and delaminate. A thermoplastic skin is more likely to deform and recover, or at least contain the damage locally. For a campervan that will encounter road vibration, stone chips, and occasional knocks, this matters.

Recyclability is the other practical difference. Thermoplastic panels can be recycled at end of life, which is relevant for builders and manufacturers working under the EU End-of-Life Vehicles (ELV) Directive. Thermoset panels, including most GRP panels, cannot be melted down and reprocessed in the same way. As European sustainability reporting requirements under the CSRD tighten, recyclable materials are becoming a procurement consideration even in the campervan sector.

How do sandwich panels compare to traditional wood and metal in campervans?

Composite sandwich panels outperform both plywood and aluminium sheet on the metrics that matter most in a campervan build: weight, longevity, and moisture resistance. Plywood absorbs moisture, swells, and rots over time, particularly in floor and wall areas exposed to condensation or washing. Aluminium is more durable but adds significant weight and conducts cold, creating thermal bridging problems.

In heavy transport applications, thermoplastic composite floors last three to four times longer than plywood under comparable conditions — typically 12 or more years versus three to five years for plywood. Over a 15-year vehicle life, that difference eliminates two to three replacement cycles. When you factor in the cost of the replacement panel, the labour to fit it, and the downtime while the vehicle is off the road, the composite option becomes cheaper per year of service even at a higher unit price.

For campervan builders, the practical advantages are:

No moisture absorption, so no swelling, warping, or rot in wet areas
Lower weight than equivalent plywood-plus-insulation assemblies
A finished surface on wall panels, removing the need for a separate cladding layer
Consistent mechanical properties that do not vary with grain direction the way timber does

What panel thickness and dimensions should a campervan build use?

Wall panels in campervan builds typically range from 17 mm to 30 mm thick, depending on the insulation performance and structural stiffness required. Floor panels generally need greater thickness and a denser core to handle point loads from furniture legs, water tanks, and occupant movement. A 30 mm PP honeycomb floor panel is self-supporting in many configurations, removing the need for a separate aluminium subframe beneath it — which saves both weight and a production step.

For wall applications, a cross-ply skin architecture is worth specifying. Cross-ply skins have fibres oriented at 0° and 90° in alternating layers, which equalises mechanical properties in both directions. This means the panel performs consistently whether it is installed vertically or horizontally — useful when cutting panels to fit irregular van geometries.

Standard off-the-shelf panel sizes rarely match the interior dimensions of a specific van model. Most professional campervan converters work with panels cut to their exact floor plan, which avoids waste and ensures clean joints. Maximum panel dimensions from specialist manufacturers can reach 13,500 mm × 2,950 mm, giving converters the option to cut multiple sections from a single large sheet rather than joining smaller pieces.

Where can you source custom-size composite sandwich panels in Europe?

Custom-dimension composite sandwich panels for campervan and coachbuilding vehicle conversion applications are available from specialist thermoplastic composite manufacturers based in Europe. Sourcing from a European manufacturer gives you shorter lead times, consistent quality across repeat orders, and direct technical support during integration — none of which are reliably available from low-cost import suppliers.

When evaluating a supplier, the questions worth asking are:

Can they supply panels cut to your exact dimensions, or only standard sheet sizes?
Do they offer different core densities and skin configurations, or only one standard build-up?
Can they provide test data referenced to European standards such as EN ISO 527 for tensile performance?
Do they offer edge sealing or edge banding to protect the core from moisture ingress at cut edges?

Edge protection is worth raising specifically. Cut panel edges expose the core to moisture and UV, which degrades performance over time. Sealed or banded edges are standard practice in professional vehicle builds and extend panel service life significantly.

How Compoform Helps with Campervan and Coachbuilding Panel Specification

We manufacture fully custom thermoplastic sandwich panels for coachbuilding, caravan, and vehicle conversion applications. Every panel is made to order — you specify the core material (PP foam or PP honeycomb), core thickness and density, skin architecture, number of plies, and finished dimensions. We cut panels to your exact requirements, up to 13,500 mm × 2,950 mm × 150 mm, from our production facility in the Netherlands.

What we bring beyond the panel itself:

Application review: Before production, we review your design and flag any configuration choices that could cause problems during assembly or in service — core density too low for your floor load, skin weight mismatched to your structural requirement, or edge details that need sealing.
Configuration flexibility: PP foam cores are available in six density grades from 40 to 140 kg/m³. PP honeycomb cores are available at 140 kg/m³. Skin options include cross-ply and multi-ply glass-fibre laminates with PET-film or anti-skid finishes.
European manufacturing and standards: All panels are 100% European-made. Test data are referenced to EN ISO 527 and ISO 14125, the standards your procurement team and certification bodies will expect.
Ongoing support: We stay involved through integration, not just the initial order. If you encounter a fit or performance issue during your build, we work through it with you.

If you are specifying panels for a campervan conversion, coachbuilt vehicle, or production caravan programme, speak with our engineering team about your floor plan dimensions, load requirements, and surface finish needs. We will recommend the right panel configuration for your application before you commit to production.