ACP Basics · Reference Guide

What Is Aluminium Composite Panel (ACP)?

Aluminium Composite Panel, commonly known as ACP, is a lightweight composite sheet made from two aluminium skins bonded to a core material. It is widely used for building facades, cladding, interiors, signage, columns, canopies, and architectural features.

The real question is not only “what is ACP?” The real question is: what type of ACP, tested under which standard, installed in which facade system, and accepted under which regulation?

ACP in one minute

If you only remember one thing, remember this: ACP is not just a decorative panel. It is one component inside a complete facade system. Two panels may look identical from the outside but perform very differently depending on core material, coating, installation system, fire testing, and local regulations.

Definition

Basic meaning

What does ACP stand for?

ACP stands for Aluminium Composite Panel. It is also called ACM, which means Aluminium Composite Material. The panel is normally made by bonding aluminium sheets to both sides of a central core under heat and pressure.

Simple definition

ACP is a flat, lightweight, factory-made cladding material that combines aluminium skins, bonding layers, coating, and a core into one engineered panel.

Anatomy

Panel layers

ACP structure explained

A typical aluminium composite panel is made from several layers. Each layer has a role in appearance, bonding, durability, rigidity, and fire behaviour.

Typical ACP layers

Protective film
Decorative coating such as PVDF, FEVE, polyester, or special finish
Primer layer
Front aluminium skin
Bonding layer
Core material
Bonding layer
Rear aluminium skin
Rear coating or service coating

The quality of these layers decides how the panel looks, bends, ages, bonds, and performs on a real building.

Why It Matters

Design and performance

Why architects and contractors use ACP

Lightweight

Lower building load

ACP is much lighter than many solid cladding materials, which helps reduce structural load and installation difficulty.

Flatness

Clean facade appearance

ACP provides a smooth, flat surface suitable for modern architectural elevations.

Fabrication

Easy to shape

ACP can be routed, folded, curved, cut, drilled, and fabricated into cassette systems.

Finish

Wide design range

ACP is available in solid colours, metallic finishes, wood, stone, marble, brushed, mirror, and custom effects.

Core Types

Fire behaviour starts inside

ACP core types explained

The most important hidden part of ACP is the core. The core strongly affects fire behaviour, weight, rigidity, and regulatory acceptance.

PE Core

Polyethylene core ACP

A plastic-rich core. It may be suitable for limited uses but requires careful review for facade fire safety.

FR Core

Fire-retardant core ACP

Contains mineral fillers to reduce fire contribution compared with PE core products.

A2 ACP

Highly mineral-filled ACP

Designed to achieve A2 fire classification under applicable European fire testing routes.

A1 ACP

Non-combustible ACP

Designed to achieve A1 classification where non-combustibility is required by regulation or specification.

System Thinking

Panel vs facade

ACP is not the same as a facade system

This is one of the biggest misunderstandings in the cladding industry. ACP is a material. A facade system is the full assembly installed on a building.

A facade system may include

ACP panels
Aluminium or steel subframe
Brackets and fasteners
Insulation
Air cavity
Fire barriers and cavity barriers
Sealants and gaskets
Joint design and fixing method

A good panel installed in a poor system can still fail. A facade should be judged as an assembly, not only as a product.

Comparisons

Material selection

ACP compared with other cladding materials

Material	Strength	Main consideration
ACP	Lightweight, flat, flexible design	Core type and system fire performance
Solid aluminium	Metallic, robust, simple material identity	Flatness, oil canning, cost, weight
HPL	Decorative and impact resistant	Fire rating, weathering, fixing system
Fibre cement	Mineral-based and durable	Weight, edge treatment, installation care
Stone cladding	Natural premium appearance	Weight, anchoring, breakage, cost

Misconceptions

Common mistakes

Common ACP misconceptions

Misconception 1

All ACP is fire rated

False. Fire performance depends mainly on core composition, test classification, and system design.

Misconception 2

FR and A2 are the same

False. FR and A2 usually represent different levels of mineral content and fire classification.

Misconception 3

NFPA 285 is a product test

False. NFPA 285 evaluates an exterior wall assembly, not only an ACP sheet.

Misconception 4

Thicker means safer

False. Thickness alone does not define fire performance, bonding quality, or regulatory suitability.

Decision Chain

How to understand ACP properly

ACP knowledge sequence

What is ACP?
ACP anatomy
ACP core types
Reaction to fire
Fire testing standards
Product testing vs system testing
Facade systems
Installation
Procurement
Regulations

Glossary

Terms to know

ACP glossary

Core

The central material between two aluminium skins.

Skin

The aluminium sheet on the front and rear side of the panel.

PVDF

A high-performance coating system often used for exterior facade panels.

Cavity barrier

A fire safety component designed to restrict fire and smoke spread inside facade cavities.

FAQ

Quick answers

Frequently asked questions

What is ACP in construction?

ACP means Aluminium Composite Panel. It is a composite cladding sheet used for facades, interiors, signage, and architectural applications.

What is ACP made of?

ACP is made of two aluminium skins bonded to a core material. It also includes coating, primer, bonding layers, and rear coating.

Is ACP fire rated?

Some ACP products are fire rated, while others are not. Fire performance depends on core material, classification, testing standard, and facade system design.

What is the difference between PE, FR, A2 and A1 ACP?

These terms generally relate to the core composition and fire performance level. PE has more plastic content, FR contains fire-retardant minerals, A2 is highly mineral-filled, and A1 is designed for non-combustible classification.

Is ACP the same as a facade system?

No. ACP is only one material inside a facade system. The complete system includes panels, subframe, fasteners, insulation, cavity barriers, joints, and installation method.

What thickness is ACP?

ACP is commonly available in 3 mm, 4 mm, 5 mm, and project-specific thicknesses. 4 mm is widely used for facade applications.

Foundation pages

ACP Anatomy Explained

Understand the layers, skins, coating, bonding, and core.

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Materials

ACP Core Types Explained

PE, FR, A2, A1 and what changes inside.

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Fire Safety

ACP Fire Safety Guide

Learn reaction to fire, combustibility, smoke, droplets, and fire load.

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Systems

What Is A Facade System?

Understand why the complete assembly matters.

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