Sandwich panels can be produced across a wide thickness range, typically from around 10 mm up to 150 mm or more depending on the manufacturer and application. The right thickness depends on the structural load the panel must carry, the core material used, and the constraints of the assembly it fits into. The questions below unpack the key factors that determine panel thickness, how core materials influence the decision, and what thickness ranges suit common transport and industrial and transport panel applications.
What determines the maximum thickness of a sandwich panel?
The maximum thickness of a sandwich panel is determined by three main factors: the production equipment available, the structural requirements of the application, and the physical properties of the core material. Most manufacturers set an upper limit based on what their production line can process consistently and accurately.
On the production side, continuous lamination lines have physical constraints on the gap between press rollers or platens. At Compoform, our 72-meter semi-automatic production line can produce panels up to 150 mm thick and up to 13,500 mm long by 2,950 mm wide. That upper limit reflects both equipment capability and the practical handling requirements of very thick composite panels.
On the structural side, increasing thickness beyond what the application demands adds weight without adding useful performance. Engineers specify thickness to meet a defined load or stiffness target, not to maximize it. The skin architecture, the core density, and the span between supports all interact to define the minimum thickness that meets the requirement. Going thicker than necessary costs money and payload capacity.
What thickness range is standard for composite sandwich panels?
Standard composite sandwich panels for industrial and transport applications typically range from 10 mm to 50 mm, with the most common configurations falling between 15 mm and 30 mm. Thinner panels below 15 mm suit lightweight cladding and scaffolding boards, while panels above 30 mm are used where high bending loads or thermal insulation requirements demand greater cross-section depth.
Our own certified product range covers configurations from 11 mm scaffolding panels up to 30 mm heavy-duty floor panels, with wall panel variants at 17 mm, 20 mm, and 30 mm. These thicknesses reflect the most common structural demands across truck bodies, trailers, and commercial vehicle interiors. For applications outside this range, custom thicknesses are available.
It is worth noting that “standard” varies by application segment. A scaffolding plank operates under very different load conditions than a trailer floor, so the thickness that is routine in one context may be excessive or insufficient in another.
Does a thicker sandwich panel always mean better performance?
No. A thicker sandwich panel does not automatically deliver better performance. Thickness increases the cross-section depth, which improves bending stiffness and absolute load capacity, but it also adds weight and material cost. The relationship between thickness and performance depends entirely on the load case, the core material, and the skin specification.
A useful illustration: our 30 mm floor panel sustains an average maximum load of 5,647 N in standardized bending tests, compared to 3,240 N for the 15 mm variant. The thicker panel carries more load in absolute terms. However, the 30 mm panel also weighs significantly more per square meter. For a truck body floor, that additional weight reduces payload capacity, which directly affects the operator’s revenue per trip.
The goal is to find the minimum thickness that meets the structural requirement, not the maximum thickness available. Oversized panels waste material, add dead weight, and in transport applications, reduce the payload that can legally be carried. In electric trucks and vans, every kilogram of structural dead weight also reduces battery range per charge, making over-specification a range argument as well as a payload argument. EV fleet procurement teams increasingly treat structural weight as a range variable, not just a cost variable.
How does core material affect how thick a panel can be?
Core material directly controls how efficiently a sandwich panel uses its thickness. A denser or structurally stronger core allows a thinner panel to meet the same load requirement, while a lower-density core may need greater thickness to achieve equivalent stiffness. The core material also affects how the panel behaves under compression, shear, and impact.
PP foam cores
Oriented PP foam cores are available in a range of densities, from 40 kg/m³ up to 140 kg/m³. Lower-density foam cores are lighter but less stiff, so panels using them may need to be thicker to meet a given bending requirement. Higher-density foam cores pack more structural performance into the same thickness, allowing engineers to keep the panel thinner while still meeting load targets. This density range gives significant flexibility when specifying custom panel configurations.
PP honeycomb cores
PP honeycomb cores at 140 kg/m³ deliver substantially higher compressive and bending performance than foam cores of comparable thickness. This makes them the preferred choice for floor panels where concentrated loads from foot traffic, pallet trucks, or vehicle wheels are expected. Because honeycomb is structurally efficient, floor panels can often be kept at 15 mm to 30 mm while still meeting demanding load specifications. The trade-off is higher areal weight compared to foam-core wall panels of similar thickness.
What panel thickness is right for trucks, trailers, and vehicle bodies?
For truck bodies and trailer applications, the most common sandwich panel thicknesses are 15 mm to 30 mm for floor panels and 17 mm to 20 mm for sidewalls. Floor panels carry higher concentrated loads and typically use PP honeycomb cores, while sidewalls prioritize low weight and surface finish and use PP foam cores with PET-film skins.
A 30 mm PP honeycomb floor panel is self-supporting across standard truck body frame spacings, which means no aluminium subframe is required beneath it. Removing the subframe eliminates a production step for the body builder and reduces the total structural weight of the vehicle, freeing payload capacity. Over a 15-year vehicle life, a composite floor also eliminates two to three plywood replacement cycles. When you factor in panel cost, installation labour, and vehicle downtime for each replacement, the composite floor is cheaper per year of service even at a higher unit price.
For electric trucks and vans, the weight argument carries additional force. Lighter body structures extend battery range per charge. Fleet operators specifying EV vehicles in 2026 increasingly ask about structural weight as part of the procurement conversation, not just payload capacity.
Can sandwich panels be produced in custom thicknesses?
Yes. Sandwich panels can be produced in custom thicknesses outside standard catalogue configurations. Most specialist manufacturers, including those using continuous lamination processes, can adjust core thickness to meet a specific structural or dimensional requirement. Custom thickness production requires a defined load specification and, in most cases, a minimum order volume to justify the setup.
Custom thickness is particularly relevant when a panel must fit within a defined envelope, such as a body structure with fixed internal height, or when a standard thickness either over- or underperforms for the application. Specifying the correct custom thickness from the outset avoids costly redesign later in the production process.
How Compoform Helps You Specify the Right Panel Thickness
We work with truck body builders, trailer manufacturers, and vehicle assemblers to identify the panel thickness that meets their structural requirements without adding unnecessary weight or cost. Our standard range covers configurations from 11 mm to 30 mm, and we produce custom thicknesses up to 150 mm for applications that fall outside that range.
When you bring us a project, we review:
- The load case — floor loads, wall loads, point loads, and distributed loads relevant to your application
- The dimensional envelope — the maximum thickness the structure can accommodate without affecting internal volume or vehicle height
- The weight budget — the structural dead weight target that protects payload capacity and, for EV fleets, battery range per charge
- The surface requirement — whether the panel needs a finished decorative surface, an anti-skid finish, or a substrate for further processing
- The production process — how the panel integrates into your assembly line, including cutting, edge treatment, and joining methods
Our panels are 100% European-made at our facilities in Beek and Ospel, the Netherlands, and are available in custom dimensions up to 13,500 mm × 2,950 mm. We cut panels to your exact specification, so you receive parts ready for assembly rather than sheet material requiring further conversion.
If you are specifying panels for a truck body, trailer floor, or commercial vehicle application, speak with our engineering team today before finalizing your design. We review your configuration, flag potential issues, and optimize the panel specification for your assembly process before production begins.