What Is AS4284?

If you’re involved in designing or constructing commercial buildings in Australia, you may come across the question:

What is AS4284?

AS4284 is the Australian Standard that specifies the testing methods for the building envelope, particularly external wall systems, curtain walls, windows, doors, and façade systems. It evaluates how these systems perform under simulated environmental conditions such as wind pressure, air infiltration, water penetration, and structural movement.

Unlike AS2047, which establishes performance requirements for standard windows and external glazed doors, AS4284 is primarily used to test the performance of complete façade systems, especially on large or high-rise buildings.

What Does AS4284 Stand For?

The full title of the standard is:

AS 4284 – Testing of Building Facades

The standard provides laboratory testing procedures to verify that a façade system can withstand Australia’s environmental conditions while maintaining its structural integrity and weather resistance.

AS4284 is widely used for:

• Curtain wall systems
• Commercial glazing systems
• High-rise building façades
• Shopfront glazing
• Unitised façade systems
• Complex architectural window systems
• Large glazed wall assemblies

Why Is AS4284 Important?

Modern buildings often feature large areas of glass and aluminium framing. These systems must withstand:

• Strong wind pressure
• Heavy rainfall
• Air leakage
• Structural movement
• Building deflection
• Serviceability loads

AS4284 provides a consistent testing methodology to demonstrate that a façade system can perform under these conditions before it is installed on a building.

What Does AS4284 Test?

AS4284 includes several performance tests designed to evaluate the complete façade system.

1. Air Infiltration Test

This test measures the amount of air that passes through the façade under specified pressure differences.

Low air leakage helps improve:

• Energy efficiency
• Indoor comfort
• HVAC performance

2. Water Penetration Test

The façade is subjected to simulated rainfall combined with positive and negative wind pressures.

The objective is to confirm that water does not penetrate into the building under the specified test conditions.

3. Structural Performance Test

The façade is exposed to design wind pressures that simulate severe weather conditions.

This test evaluates whether:

• Glass remains intact
• Aluminium framing performs correctly
• Connections remain secure
• Permanent deformation is within acceptable limits

4. Serviceability Test

This assessment measures how the façade performs under normal operating wind loads.

The system should maintain its functionality without excessive movement or damage.

5. Building Movement Test

Buildings naturally move due to:

• Wind
• Temperature changes
• Live loads
• Structural deflection

AS4284 evaluates whether the façade can accommodate these movements while maintaining weather-tightness and structural performance.

Which Buildings Require AS4284 Testing?

AS4284 is most commonly specified for:

• High-rise residential buildings
• Office towers
• Hotels
• Hospitals
• Universities
• Shopping centres
• Airports
• Commercial developments
• Mixed-use buildings

Many architects and façade consultants specify AS4284 testing when a project includes custom-designed glazing systems or complex façade assemblies.

Does Every Window Need AS4284?

No.

Most standard residential windows and doors are assessed in accordance with AS2047.

AS4284 is generally required when:

• The project uses curtain wall systems.
• The façade is custom engineered.
• Large commercial glazing systems are installed.
• The building is high-rise or architecturally complex.
• Project specifications call for façade performance testing.

What Is the Difference Between AS4284 and AS2047?

Although both standards relate to windows and glazing, they serve different purposes.

In some commercial projects, both standards may be referenced. Individual window products may comply with AS2047, while the overall façade system undergoes AS4284 testing.

Is AS4284 Mandatory?

AS4284 itself is not automatically mandatory for every building.

Whether testing is required depends on:

• The project specification
• The building classification
• The façade design
• The engineer’s requirements
• Local regulatory approvals

For many commercial developments, architects or façade consultants specify AS4284 testing to demonstrate that the façade system meets the required performance criteria.

How Does AS4284 Benefit Building Owners?

A façade system tested in accordance with AS4284 offers several advantages:

• Greater confidence in weather resistance
• Improved structural performance
• Reduced risk of water leakage
• Better long-term durability
• Enhanced building quality
• Support for project compliance requirements

Testing can also identify potential issues before installation, helping to reduce costly on-site modifications.

MEICHEN Windows & Doors for Commercial Projects

At MEICHEN Windows & Doors, we manufacture custom aluminium window and door systems for residential and commercial developments.

Our solutions can be engineered to meet project-specific performance requirements, including:

• Aluminium curtain wall systems
• Commercial window systems
• Sliding and hinged doors
• Large-format glazing
• Double glazed systems
• Low-E glazing
• Safety glazing compliant with Australian Standards

We work closely with builders, developers, architects, and façade consultants to provide solutions suitable for Australian construction projects.

Frequently Asked Questions

What is AS4284?

AS4284 is the Australian Standard that specifies laboratory testing methods for building façade systems, including curtain walls, commercial glazing, and external wall assemblies.

What does AS4284 test?

AS4284 evaluates:

• Air infiltration
• Water penetration
• Structural performance
• Serviceability
• Building movement

to verify that a façade system performs under simulated environmental conditions.

Is AS4284 the same as AS2047?

No. AS2047 applies to windows and external glazed doors, while AS4284 applies to the testing of complete building façade systems.

Is AS4284 required for residential homes?

In most standard residential projects, AS2047 is sufficient. AS4284 is generally specified for commercial, high-rise, or custom façade projects where whole-system performance testing is required.

Why is AS4284 important?

AS4284 helps verify that a façade system can resist wind, rain, and structural movement, reducing the risk of leakage and improving long-term building performance.

Conclusion

AS4284 is the Australian Standard for testing the performance of building façade systems. Rather than focusing on individual windows or doors, it assesses how an entire façade performs under realistic environmental conditions, including wind pressure, water penetration, air leakage, and structural movement.

For most residential buildings, AS2047 remains the primary standard for windows and external glazed doors. However, for commercial developments, high-rise buildings, and complex façade systems, AS4284 plays a critical role in demonstrating that the complete building envelope can meet demanding performance requirements.

Choosing façade systems designed and engineered for Australian conditions helps ensure long-term durability, weather resistance, and confidence throughout the life of the building.