Fast Supply Solutions
We match your technical product needs with the right manufacturers and quickly organize the process for competitive prices and short delivery times.
THERMAL INSULATION GUIDE
How to Select Sandwich Panel Thickness and Thermal Performance
Panel thickness is determined from the target U-value, core thermal conductivity, indoor-outdoor temperature difference, building use, joint design and local energy requirements. Different cores at the same thickness may not provide the same performance.
Direct answer
Panel thickness is determined from the target U-value, core thermal conductivity, indoor-outdoor temperature difference, building use, joint design and local energy requirements. Different cores at the same thickness may not provide the same performance.
Technical review: MDES Engineering Technical TeamUpdated: 2026-08-05
Thickness and U-value
Increasing thickness generally raises thermal resistance and lowers U-value. The actual value must use the declared core conductivity together with facings and joint geometry.
Building use
Warehouses, production areas, cold rooms and climate-controlled facilities have different temperature and humidity targets. Cold storage additionally requires condensation, vapour-control and thermal-bridge assessment.
Why do joints matter?
Poor joints, fasteners, purlins and corner details can create thermal bridges and air leakage even when the panel surface performs well. Panel and installation details must be verified as one system.
Factors affecting thickness
| Factor | Effect |
|---|---|
| Core λ-value | Material thermal conductivity |
| Panel thickness | Thermal resistance/U-value |
| Temperature difference | Required insulation level |
| Joint design | Thermal bridge/air leakage |
Key points
- Do not compare thickness alone.
- Use declared U and λ values.
- Assess condensation for cold rooms.
- Joints and fixings are part of system performance.
Frequently asked technical questions
Is a thicker panel always better?
Thermal resistance generally improves, but the optimum thickness balances core, cost, load and project needs.
Do PIR and mineral wool have the same U-value at equal thickness?
Generally not; compare declared product values because their conductivities differ.
Is U-value alone enough for cold rooms?
No. Vapour control, airtightness, joints and condensation risk must also be assessed.
Which information is required for a sandwich panel quotation?
Specify the application, roof or wall type, core material, panel thickness, steel thicknesses, colour, total area, accessories, project location and delivery point. Fire and thermal performance must be confirmed against the project specification before ordering.
Technical references
- EN 14509 self-supporting double-skin insulating panels
- EN 13501-1 reaction-to-fire classification
Related products
View Sandwich Panels »