Double Glazing in Western Australia

That position is shifting.

With the introduction of 7-star NatHERS requirements in May 2025, double glazing is moving from optional to increasingly necessary, particularly in residential construction. For builders, architects, and glaziers, this isn’t just a compliance change. It’s a shift in how glazing is specified, priced, and delivered on-site.

This guide breaks down what double glazing actually delivers in WA conditions, and where it fits as the baseline continues to move.

What’s Changed: The Move to 7-Star Homes in WA

From May 2025, new homes across Australia, including WA, are required to meet minimum 7-star energy ratings under NatHERS.

In practical terms, that means:

• Stronger thermal performance targets
• Reduced heat gain and loss through the building envelope
• Less reliance on mechanical heating and cooling

Windows and glazing are one of the biggest variables in achieving that rating.

Single glazing can still be used, but it becomes harder to make the numbers work, especially when projects include:

• Large openings
• Open-plan layouts
• West- and north-facing glazing
• Modern façade designs

That’s where double glazing starts to carry the load.

What Double Glazing Actually Does (Beyond the Basics)

An insulated glass unit (IGU) uses two panes separated by a sealed cavity. That cavity slows the transfer of heat and sound, but performance depends entirely on the build-up.

For trade professionals, the key point is this:
double glazing isn’t one product, it’s a configurable system.

1. Thermal Performance That Helps You Hit 7 Stars

The biggest driver behind IGU adoption in WA is thermal performance.

Single glazing allows:

• Rapid solar heat gain during the day
• Fast heat loss overnight

Double glazing slows both.

On-site impact:

• More stable internal temperatures
• Reduced HVAC loads
• Easier pathway to achieving NatHERS targets

When paired with Low-E coatings, IGUs become significantly more effective, particularly in managing WA’s high solar loads without blocking natural light.

Where this matters most:

• Large glazed façades
• West-facing elevations
• Homes with high glazing-to-wall ratios

2. Solar Control Without Over-Reliance on Tinting

Historically, WA projects have leaned on tinted or reflective glass to manage heat.

That works, but it often reduces daylight quality and limits design flexibility.

Double glazing allows a different approach:

• Clear or low-iron external pane
• Low-E coating inside the cavity

Result:

• Better natural light penetration
• Reduced glare compared to heavy tints
• Improved thermal performance without darkening the façade

For architects, this opens up design options that were previously difficult to achieve with single glazing alone.

3. Acoustic Performance in Growing Urban Areas

As density increases across Perth and regional centres, noise is becoming a more consistent design consideration.

Double glazing improves acoustic performance by:

• Creating separation between panes
• Allowing mixed glass thicknesses to disrupt sound transmission

For higher performance, IGUs can incorporate laminated glass such as:

• ToughGuard™ for general safety
• ToughSound™ where acoustic control is critical

High-value applications:

• Residential builds near arterial roads or rail
• Multi-residential developments
• Mixed-use precincts

4. Condensation Reduction in Conditioned Spaces

While WA isn’t a cold climate, condensation still shows up in:

• Air-conditioned homes
• Coastal environments
• High-humidity internal spaces

Double glazing reduces condensation risk by keeping the internal pane closer to room temperature.

It won’t eliminate condensation entirely, but it significantly reduces the conditions that cause it.

5. Flexibility in Glass Specification

One of the biggest advantages of IGUs is how adaptable they are.

You’re not locked into a single outcome, you can build performance into the unit.

Common IGU configurations:

• Toughened + toughened → standard safety glazing
• Laminated + toughened → improved safety and acoustics
• Low-E + clear → thermal efficiency
• Tinted + clear → solar control

This flexibility allows you to meet:

• Energy targets
• Acoustic requirements
• Safety compliance

…without redesigning the entire glazing system.

6. Where Double Glazing Is Becoming the Default

With 7-star requirements now in play, IGUs are increasingly specified as standard in:

• New residential builds targeting compliance without design compromise
• Homes with large glazing areas
• Architecturally designed projects
• Multi-residential developments

In many cases, double glazing is no longer about “upgrading”, it’s about making the design viable under current regulations.

Trade Considerations: What Changes on Site

Specifying double glazing affects more than performance, it changes how projects are delivered.

Key considerations:

• Weight — IGUs are heavier, impacting handling and installation
• Framing systems — must be compatible with IGU thickness and weight
• Lead times — more complex than single glazing
• Seal integrity — critical for long-term performance

These need to be factored in early, particularly on tight build schedules.

Single vs Double Glazing: The Real Decision

The question isn’t “is double glazing better?”

It’s:

Can this project meet performance and compliance targets without it?

In some cases, yes, particularly with smaller openings or heavily shaded designs.

But as soon as you introduce:

• Large spans of glass
• Challenging orientations
• Higher energy targets

…double glazing quickly becomes the more practical path.

The Takeaway

Double glazing in Western Australia is no longer just about comfort, it’s about compliance, performance, and design flexibility.

• It helps meet 7-star energy requirements introduced in 2025
• It stabilises internal temperatures in a high-variation climate
• It improves acoustic outcomes in denser urban environments
• It gives specifiers more control over how glazing performs

Used correctly, it simplifies the path to compliance, instead of complicating it.

Next Step

If you’re working through a residential or commercial project and need to align glazing with 7-star requirements, we can help you map the IGU configuration to real performance outcomes, from thermal targets to acoustic control and system compatibility.

Because with double glazing, the difference isn’t just two panes, it’s how the unit is specified, built, and installed.