Ventilated facades
Rainscreen cladding on concrete or steel-framed buildings, hung on aluminium rails with a drained cavity. Panels are formed into cassettes with hook-on or riveted fixings.
Guide · Wall cladding panels
Aluminium Sandwich Wall Panels: Corrugated, Honeycomb and Insulated Cores
A sandwich wall panel is a flat or curved cladding element with two aluminium skins bonded to a core, used for ventilated facades, interior partitions, ceilings and modular buildings. For most wall work the choice is between a thin all-aluminium corrugated core panel, a stiffer honeycomb panel for large formats, and an insulated panel where the wall must also provide thermal resistance. This guide is written for facade fabricators, system companies and project buyers who need the panel material.
- Panel width
- Up to about 1600 mm
- Thickness
- 3 – 8 mm corrugated; 10 – 25 mm honeycomb
- Fire
- A2-s1,d0 achievable with metal cores
- Finishes
- PVDF, polyester, anodised, wood grain
What is an aluminium sandwich wall panel?
In a wall panel, the sandwich construction does two jobs. It gives a large, flat, light panel that resists wind pressure between widely spaced rails, and it provides a durable coated face that defines the building’s appearance. The skins are usually 3003, 3105 or 5005 aluminium sheet with a PVDF or polyester coil coating; the core is aluminium (corrugated or honeycomb), mineral or an insulating foam.
Wall panels are typically part of a system: a sub-frame of aluminium rails and brackets, panel trays or cassettes with folded edges, gaskets or open joints, and a drained and ventilated cavity in front of the insulation and the structural wall. Metline supplies the aluminium materials for these systems, including the panels, coated skin coil and the extruded rails and edge profiles; the facade contractor designs, fabricates and installs the finished wall.
Aluminium corrugated composite wall panels
The corrugated core is a thin aluminium sheet formed into a wave, trapezoid or a three-dimensional cone pattern, then bonded between the two skins with a thermosetting adhesive under heat and pressure. A cone-shaped (3D) core supports the skins at points in both directions, so it behaves more uniformly than a single-direction wave and resists denting.
| Item | Typical range |
|---|---|
| Panel width | Up to about 1600 mm; length to project requirement |
| Overall thickness (H) | 3, 4, 6 and 8 mm |
| Top skin (t1) | 0.5 – 0.8 mm |
| Core sheet (tw) | 0.3 – 0.5 mm |
| Bottom skin (t2) | 0.5 – 0.8 mm |
| Skin alloys | 3003, 3105, 5005 (H14 to H46 tempers) |
| Core alloys | 1050, 1060, 3003 |
| Finishes | PVDF, polyester, anodised, brushed, wood or stone grain |
Ranges are typical industry values; confirm the exact build-up, tolerances and test data on the product datasheet.
Because the core is metal, the panel can be routed on the back skin and folded into trays, curved on a three-roll bender and drilled for fixings without the core crushing as readily as a honeycomb. That makes it a good fit for curved corners, column cladding and soffits. Its main limitation is span: a 4 – 6 mm panel needs closer supports or stiffeners than a 20 mm honeycomb panel in high wind zones.
Aluminium honeycomb sandwich wall panels
Honeycomb wall panels use an expanded aluminium honeycomb (usually 3003) between skins of about 1.0 – 1.5 mm, with total thicknesses of 10 – 25 mm. They are the choice for very large formats, for high-wind elevations and where perfect flatness matters, for example in lobbies, airports and large public buildings.
Honeycomb panels are stiffer per kilogram than corrugated panels but are more costly to produce, involve more adhesive area, and need edge closure to prevent moisture entering open cells. Shaping beyond gentle curves is harder, so complex geometry tends to favour corrugated or folded solid aluminium sheet. See our honeycomb sandwich panel guide for core grades.
Insulated sandwich panels with aluminium faces
Insulated panels combine thin metal faces with a thick core of polyurethane (PUR/PIR), mineral wool or similar, typically 40 – 200 mm. They are factory-made to EN 14509 and act as the whole wall build-up in cold stores, cleanrooms, industrial buildings and modular units. Aluminium faces are chosen over steel for corrosion resistance in food, coastal and chemical environments.
Fire performance depends strongly on the core: mineral wool cores can achieve A2-s1,d0, while foam cores are combustible and their classification depends on the complete panel. Insulated panels are not a substitute for a rainscreen panel on a high-rise facade; check the building code requirements for each wall type.
Corrugated vs honeycomb vs other wall panels
| Panel type | Core | Fire (typical) | Weight | Shaping | Relative cost |
|---|---|---|---|---|---|
| Corrugated composite (ACCP) | Formed aluminium sheet | A2-s1,d0 | Light | Fold, curve, mill easily | Medium |
| Honeycomb sandwich | Aluminium honeycomb | A2-s1,d0 | Light for its stiffness | Gentle curves; edge closure needed | Higher |
| Aluminium foam sandwich | Closed-cell aluminium foam | A1/A2 when all-metal | Medium | Limited | Highest |
| ACP, FR core | Mineral-filled polymer | B-s1,d0 | Light | Rout and fold | Low |
| ACP, PE core | Polyethylene | Combustible | Light | Rout and fold | Lowest |
| Insulated (PIR / mineral wool) | Insulation foam or wool | Core-dependent | Medium | Flat panels only | Medium |
Corrugated and honeycomb panels both reach the same fire class; the choice between them is mainly about span, flatness, shaping and cost. For a standard rainscreen with cassettes up to about 1.5 × 3 m and supports at normal spacing, corrugated panels usually do the job at lower cost. For very large panels, high wind loads or premium flatness, honeycomb is safer.
Where sandwich wall panels are used
Interior wall systems
Partitions and feature walls in offices, hotels, hospitals and transport hubs, often on keel-slot or modular frames. Panels resist impact and are easy to clean.
Ceilings and soffits
Lightweight panels on suspension systems for public spaces, canopies and walkways, including curved and perforated designs.
Cleanrooms and healthcare
Smooth, non-porous, easy-to-clean walls for operating theatres, laboratories and pharmaceutical areas.
Modular and prefabricated buildings
Factory-finished wall panels for modular units, kiosks and site buildings, installed dry.
Transport hubs
Airports, metro and rail stations, where impact resistance, fire class and long-term appearance are critical.
Design, fabrication and fixing guidance
- Wind load: size panel thickness and support spacing to the project wind pressure; ask for tested load-span data for the chosen build-up.
- Thermal movement: allow about 2.4 mm per metre per 100 °C; use slotted holes or sliding cassette hooks and joints of roughly 10 – 20 mm.
- Folding: rout the back skin with the correct V or U groove for the panel thickness, and fold once; reworking cracks the face coating.
- Edges: seal or close cut edges on honeycomb panels exposed to weather.
- Fixings: use aluminium or stainless fasteners with isolating washers; avoid direct contact with copper or untreated steel.
- Colour consistency: order each elevation from one coating batch and keep panel direction arrows consistent on metallic finishes.
- Protective film: remove within the period stated by the coater after installation to avoid adhesive residue.
Standards and tests to ask for
| Standard | What it covers |
|---|---|
| EN 13501-1 | Reaction-to-fire classification (A1, A2, B … with smoke and droplet ratings) |
| NFPA 285 / ASTM E84 | US fire tests for wall assemblies and surface burning |
| EN 14509 | Factory-made insulated sandwich panels with metal faces |
| EN 1999 (Eurocode 9) | Design of aluminium structures, including sub-frames |
| EN 1396 / AAMA 2605 | Coil-coated aluminium sheet and high-performance organic coatings |
| ASTM C393 / ASTM D1781 | Sandwich core shear and climbing-drum peel (bond strength) tests |
For a facade tender, ask the panel supplier for the fire classification report covering the exact thickness and core, peel and bond test results, coating warranty terms and colour data, and load-span tables. Keep these with the project file; building control and insurers increasingly ask for them at handover.
References and standards
- EN 13501-1 – Fire classification of construction products and building elements
- EN 14509-1 – Double skin metal faced insulating panels for self-supporting applications
- NFPA 285 – Standard fire test method for exterior non-load-bearing wall assemblies
- EN 1999-1-1 (Eurocode 9) – Design of aluminium structures
- European Aluminium – Aluminium in buildings
Sandwich wall panels: frequently asked questions
Can an aluminium corrugated panel replace a honeycomb panel?
In most standard rainscreen and interior applications, yes: both reach A2-s1,d0 and the corrugated panel is thinner and usually cheaper. For very large panels, high wind loads or premium flatness, honeycomb remains the safer choice because of its higher stiffness.
What thickness of sandwich wall panel do I need?
Interior walls commonly use 3 – 4 mm corrugated panels; exterior cassettes 4 – 6 mm corrugated or 10 – 20 mm honeycomb. The final thickness depends on wind load, panel size and support spacing, so check against the manufacturer’s load-span data.
Are aluminum sandwich wall panels non-combustible?
All-aluminium corrugated and honeycomb panels typically achieve A2-s1,d0 to EN 13501-1. Panels with PE cores do not; FR cores are usually B-s1,d0. The classification report for the exact product and fixing system is what counts.
Which finishes are available?
PVDF and polyester coil coatings in RAL and custom colours, anodised, brushed, mirror, and printed wood or stone grain finishes. PVDF is recommended for exterior facades.
Does Metline install wall panel systems?
No. Metline supplies the aluminium materials: sandwich panels, coated skin coil and the extruded rails and profiles used in wall systems. Design, fabrication and installation are carried out by the facade contractor or system company.
Sourcing aluminium wall panels for a project?
Send the panel type, thickness, finish, quantity and fire class required, and our team will reply with options and a delivered price.
