Double-Glazed Aluminium Windows and Doors

Double-Glazed Aluminium Windows and Doors

Double-glazed aluminium windows and doors combine two panes of glass with a sealed space between them and an aluminium framing system to create a window or door assembly designed for improved thermal, acoustic and comfort performance compared with many basic single-glazed configurations.

For Australian homes, renovations, commercial buildings and architectural projects, double glazing can be an important part of improving building performance. However, the glass is only one part of the equation. The aluminium frame, glazing configuration, seals, hardware, installation and overall building design all influence how the completed system performs.

EZ Windows supplies double-glazed aluminium windows and doors in a range of configurations for residential, architectural and commercial applications, with options selected according to the requirements of each project.

Whether you are building a new home, replacing existing windows, designing a premium architectural project or sourcing windows and doors for a commercial development, understanding the complete system is essential.

What Are Double-Glazed Aluminium Windows and Doors?

Double-glazed aluminium windows and doors use an insulated glass unit, commonly referred to as an IGU, installed within a suitable aluminium window or door frame.

An IGU generally consists of:

  • Two panes of glass
  • A sealed cavity between the panes
  • A spacer separating the glass panes
  • A sealed perimeter system
  • Air or another specified gas within the cavity, depending on the glazing specification

The aluminium frame then holds and supports the glazing unit as part of the complete window or door system.

The important distinction is that double glazing describes the glass construction, not the entire performance of the window or door.

A high-performance glazing unit installed into one framing system may perform differently from the same or similar glazing installed into another.

For this reason, buyers should consider the complete frame-and-glass system rather than selecting windows based solely on the words “double glazed”.

How Does Double Glazing Work?

Double glazing works by creating an insulating space between two panes of glass, reducing the direct transfer of heat through the glazing compared with a basic single pane of similar glass.

The sealed cavity helps reduce heat transfer through the glass assembly.

Depending on the specified system, double glazing can contribute to:

  • Improved thermal performance
  • Greater internal comfort
  • Reduced heat loss during colder conditions
  • Reduced unwanted heat transfer during warmer conditions
  • Improved acoustic performance in suitable configurations
  • Reduced internal surface temperature differences
  • Improved overall building energy performance when correctly integrated into the building design

Actual performance depends on the complete window or door configuration.

Are Double-Glazed Aluminium Windows Energy Efficient?

Double-glazed aluminium windows can form part of an energy-efficient building, but double glazing alone does not determine the energy efficiency of a window.

Whole-window performance is affected by factors including:

  • Aluminium frame design
  • Whether the frame is standard or thermally broken
  • Glass type
  • Glass thickness
  • Cavity configuration
  • Low-emissivity coatings where specified
  • Spacer system
  • Window size
  • Opening configuration
  • Orientation
  • Shading
  • Air leakage
  • Installation
  • Building-envelope design

This is why two apparently similar double-glazed windows can have different performance characteristics.

Where a project has specific energy-performance requirements, the window and glazing selection should be coordinated with the project’s approved energy assessment and relevant project professionals.

Double Glazing and Aluminium Frames

Aluminium is widely used for windows and doors because of its strength, durability, relatively slim profiles and suitability for contemporary architectural designs.

It is particularly useful where projects require:

  • Large areas of glazing
  • Modern window proportions
  • Large sliding or stacker doors
  • Custom configurations
  • Architectural colours
  • Low-maintenance framing
  • Residential and commercial applications

However, aluminium is naturally conductive.

This means the design of the aluminium framing system becomes particularly important when higher levels of thermal performance are required.

Standard Aluminium vs Thermally Broken Aluminium

One of the most important decisions when specifying double-glazed aluminium windows and doors is whether the project requires a standard aluminium frame or a thermally broken system.

Standard Aluminium Frames

In a conventional aluminium frame, aluminium generally provides a continuous conductive pathway between internal and external parts of the frame.

Double glazing can still improve the glazing component of the window, but heat can continue to transfer through the aluminium framing.

Standard aluminium systems can be suitable for many applications depending on the project requirements.

Thermally Broken Aluminium Frames

A thermally broken aluminium frame incorporates a thermal barrier designed to reduce direct thermal conductivity between internal and external aluminium sections.

When combined with appropriate double glazing, thermally broken framing can provide substantially different whole-window thermal characteristics from a conventional aluminium frame.

It does not eliminate all heat transfer or guarantee that condensation can never occur.

The correct solution depends on climate, building design, glazing, orientation, energy assessment and project requirements.

What Are the Benefits of Double-Glazed Aluminium Windows and Doors?

The primary benefits can include improved comfort, thermal performance, acoustic performance and access to larger architectural glazing configurations.

Improved Internal Comfort

One of the most noticeable advantages of correctly specified double glazing can be improved comfort near windows.

During cold conditions, internal glass surfaces can remain warmer than comparable basic single glazing.

During hot conditions, the glazing system can help reduce unwanted heat transfer, particularly when glass selection, orientation and shading are properly considered.

Improved Thermal Performance

Double glazing can reduce heat transfer through the glazed component of the window.

For projects seeking higher performance, it can be combined with:

  • Thermally broken aluminium frames
  • Low-E glass
  • Appropriate cavity widths
  • Suitable spacer technologies
  • Solar-control glass
  • External shading
  • Building insulation
  • Correct orientation and design

The best result comes from treating windows as part of the complete building envelope.

Acoustic Performance

Double glazing can also contribute to acoustic performance, although double glazing should not automatically be considered soundproof glazing.

Acoustic performance depends on factors such as:

  • Glass thickness
  • Different glass thicknesses between panes
  • Laminated glass
  • Cavity width
  • Frame design
  • Seals
  • Opening type
  • Installation quality
  • Building construction surrounding the window

Projects near major roads, rail corridors, airports or other significant noise sources may require a project-specific acoustic assessment.

Architectural Appearance

Aluminium framing is particularly suited to contemporary architecture.

Depending on the selected system, aluminium windows and doors can provide:

  • Slim architectural sightlines
  • Large glazed areas
  • Strong horizontal or vertical proportions
  • Dark contemporary finishes
  • Custom powder-coated colours
  • Large sliding-door openings
  • Fixed feature glazing
  • Integration with aluminium window shrouds and façade elements

This makes double-glazed aluminium systems suitable for both performance-focused and design-led projects.

Durability and Maintenance

Aluminium does not require the same regular painting typically associated with some traditional window materials.

Appropriate cleaning and maintenance remain necessary, particularly for hardware, tracks, drainage paths, glass, seals and powder-coated surfaces.

Maintenance requirements can vary considerably depending on environmental exposure.

Double-Glazed Aluminium Windows

Double glazing can be incorporated into many aluminium window configurations.

Double-Glazed Awning Windows

Awning windows are hinged and open outward, usually from the bottom.

They can provide ventilation while maintaining a relatively compact opening configuration.

Double-glazed awning windows are commonly considered for:

  • Bedrooms
  • Living areas
  • Kitchens
  • Bathrooms where appropriate
  • Multi-residential developments
  • Commercial buildings
  • Architectural homes

Where awning windows are installed inside architectural window shrouds or other façade projections, sufficient opening clearance must be considered.

Double-Glazed Sliding Windows

Sliding windows are popular where projecting window sashes are undesirable.

They can be useful beside:

  • Walkways
  • Patios
  • Balconies
  • Decks
  • Outdoor entertaining areas
  • Restricted external spaces

The sliding mechanism and frame configuration should be selected to accommodate the required glass weight and system performance.

Double-Glazed Fixed Windows

Fixed windows contain no opening sash and can be an effective solution where natural ventilation is not required through that particular opening.

They are often used for:

  • Feature glazing
  • Large architectural windows
  • Stairwells
  • High-level glazing
  • Commercial façades
  • Living areas
  • Combination window assemblies

Fixed windows can also be combined with awning, sliding or other operable windows.

Double-Glazed Sashless Windows

Sashless systems provide a distinctive appearance by reducing the visual prominence of conventional sash framing around the moving glass.

Where double-glazed sashless solutions are being considered, availability and performance will depend on the selected proprietary system and project requirements.

Double-Glazed Aluminium Doors

Large glazed doors can represent a substantial proportion of the external building envelope.

For this reason, glass selection, framing, hardware and threshold detailing become particularly important.

Double-Glazed Sliding Doors

Aluminium sliding doors are widely used to connect internal living spaces with:

  • Patios
  • Balconies
  • Courtyards
  • Gardens
  • Alfresco areas
  • Commercial outdoor areas

Large double-glazed panels can become very heavy.

Panel dimensions therefore affect:

  • Glass selection
  • Frame selection
  • Roller and hardware requirements
  • Transport
  • Site handling
  • Installation
  • Structural considerations

There is no single universal maximum panel size suitable for every project.

Double-Glazed Stacker Doors

Stacker doors use multiple sliding panels to create a wider opening than many conventional two-panel sliding-door arrangements.

They are particularly popular where homeowners and architects want a strong connection between indoor and outdoor living areas.

Double glazing can be incorporated where the selected system is designed for the required glazing thickness and panel weights.

Double-Glazed Bifold Doors

Bifold doors fold multiple panels together to create a broad opening.

Because multiple glazed panels, hinges, rollers and hardware operate together, correct system selection becomes important as glass weight increases.

Double-glazed bifold doors can provide an impressive architectural opening, but buyers should consider the balance between:

  • Opening width
  • Panel size
  • Glass weight
  • Hardware
  • Threshold design
  • Weather performance
  • Maintenance
  • Project exposure

Double-Glazed Hinged Doors

Hinged aluminium doors can also incorporate double glazing.

They can be used for residential entrances, side access, courtyards and selected commercial applications depending on the system.

Double Glazing vs Single Glazing

The fundamental difference is that single glazing uses one pane of glass, while double glazing uses two panes separated by a sealed cavity.

In broad terms:

Feature Single Glazing Double Glazing
Glass panes One Two
Sealed insulating cavity No Yes
Thermal potential Lower Higher when appropriately specified
Acoustic potential Configuration dependent Can be improved with appropriate specification
Glass weight Generally lower Generally higher
Frame requirements Standard systems available Must accommodate IGU
Initial cost Generally lower Generally higher
System complexity Lower Higher

This comparison is deliberately general.

Actual thermal and acoustic performance should be determined from the specific products and configurations being considered.

What Glass Can Be Used in Double-Glazed Aluminium Windows?

Double glazing is not one standard glass specification.

Depending on the project, an insulated glass unit may incorporate different glass products and configurations.

Options may include:

  • Clear glass
  • Toned glass
  • Toughened glass
  • Laminated glass
  • Low-E glass
  • Solar-control glass
  • Different pane thicknesses
  • Acoustic glazing configurations
  • Safety glazing where required

The correct selection depends on the location of the glass, panel dimensions, safety requirements, energy requirements, acoustic objectives and other project considerations.

What Is Low-E Glass?

Low-emissivity, or Low-E, glass incorporates a coating designed to modify the way radiant heat passes through the glazing.

Low-E glass can form part of a higher-performance double-glazing specification.

It should not, however, be considered independently from the rest of the window.

The complete configuration may need to consider:

  • Glass coating
  • Glass make-up
  • Aluminium frame
  • Thermal break
  • Cavity
  • Spacer
  • Window orientation
  • Shading
  • Solar exposure

The appropriate combination should reflect the project’s required performance.

Can Double Glazing Reduce Outside Noise?

Yes, appropriately specified double glazing can help reduce external noise, but the amount of improvement depends on the complete acoustic construction.

Simply adding a second pane does not automatically provide the optimum acoustic result.

For demanding applications, the glazing specification may use different glass thicknesses or laminated glass to target particular sound frequencies.

Equally important are the frame, seals, opening configuration and installation.

Noise can also enter a building through:

  • Walls
  • Roofs
  • Doors
  • Ventilation openings
  • Gaps
  • Building penetrations

For projects with defined acoustic targets, glazing should be selected according to the project’s acoustic requirements rather than relying on a generic double-glazing description.

Does Double Glazing Stop Condensation?

Double glazing can reduce the likelihood of condensation on internal glass surfaces under some conditions, but it cannot guarantee that condensation will never occur.

Condensation is influenced by:

  • Indoor humidity
  • Outdoor temperature
  • Internal temperature
  • Ventilation
  • Glass temperature
  • Frame temperature
  • Building insulation
  • Thermal bridging
  • Occupancy
  • Moisture generation inside the building

Thermally broken frames can further reduce thermal conductivity through the aluminium frame, but they also do not eliminate every possible condensation condition.

Are Double-Glazed Windows Completely Waterproof?

No window or door should be described as completely waterproof in every possible condition.

Window and door systems are designed and tested for specified levels of weather and water resistance according to their system characteristics and intended applications.

Performance can also be affected by:

  • Building exposure
  • Wind pressure
  • Installation
  • Flashings
  • Sealants
  • Membranes
  • Drainage
  • Surrounding cladding
  • Building movement
  • Maintenance

An open window can also admit wind-driven rain.

The complete building envelope must therefore be properly coordinated.

Double-Glazed Sliding Doors, Thresholds and Drainage

Large glazed doors require particular attention to external levels and drainage.

The door itself is only one component of the overall weather-management strategy.

The project should coordinate:

  • Door threshold
  • External paving
  • Balcony or deck levels
  • Falls
  • Drainage
  • Flashings
  • Waterproofing membranes
  • Sealants
  • Adjacent wall construction

Water appearing near a door does not necessarily mean that the water originated through the door itself.

Surrounding construction and drainage conditions should also be investigated.

Double Glazing for New Homes

Double-glazed aluminium windows and doors are increasingly considered during the design of new homes where energy efficiency, comfort, acoustic performance or premium architectural appearance are priorities.

Selecting windows early allows the project team to coordinate:

  • Opening sizes
  • Energy assessment
  • Glass specification
  • Frame system
  • Structural openings
  • External finishes
  • Window shrouds
  • Screens
  • Internal finishes
  • Installation details

Early coordination can reduce unnecessary changes later in the construction process.

Double Glazing for Renovations

Double glazing can also be incorporated into renovation and replacement-window projects.

Existing buildings, however, can introduce additional considerations.

These may include:

  • Existing opening dimensions
  • Wall construction
  • Existing flashings
  • Internal reveals
  • External cladding
  • Access
  • Structural conditions
  • Existing waterproofing
  • Floor and paving levels
  • Removal of existing windows

A replacement project should therefore be assessed on its actual site conditions rather than assuming that a new double-glazed unit can simply be substituted for the existing window without further consideration.

Double Glazing for Commercial Buildings

Double-glazed aluminium windows and doors can be used across many commercial and institutional projects, including:

  • Offices
  • Schools
  • Childcare centres
  • Government buildings
  • Multi-residential developments
  • Retail buildings
  • Community facilities
  • Mixed-use developments

Commercial projects may have more detailed requirements for energy, acoustic, structural, safety, access and façade performance.

EZ Windows manufactures and supplies within the agreed scope and according to approved project information.

Where engineering, energy modelling, acoustic assessment or other specialist certification is required, those requirements should be established by the appropriately appointed project professionals.

Double Glazing for Architects and Building Designers

For architects and designers, the value of aluminium systems extends beyond thermal performance.

Windows and doors form a major part of the architectural expression of a façade.

Design considerations may include:

  • Frame proportions
  • Sightlines
  • Mullion locations
  • Opening direction
  • Glass size
  • Door-panel width
  • Powder-coat colour
  • Window shrouds
  • Façade depth
  • Shadow lines
  • Screening
  • Internal and external finishes

EZ Windows can work from approved architectural documentation and project information to manufacture or source appropriate window and door solutions within the agreed scope.

Double-Glazed Aluminium Windows for Builders

Builders require more than a window price.

A successful package also requires coordination around:

  • Window schedules
  • Architectural drawings
  • Structural openings
  • Glass specifications
  • Finishes
  • Shop drawings where applicable
  • Site dimensions
  • Delivery
  • Access
  • Installation scope
  • Construction program

Providing complete and accurate information during quotation and ordering helps reduce ambiguity as the project progresses.

Custom Double-Glazed Aluminium Windows and Doors

Custom manufacturing allows windows and doors to be configured around individual project requirements rather than relying solely on standard retail dimensions.

Depending on the selected framing system, customisation may include:

  • Width and height
  • Window configuration
  • Door configuration
  • Mullion positions
  • Transoms
  • Fixed and opening combinations
  • Glass selection
  • Powder-coat finish
  • Hardware
  • Screens
  • Architectural coordination

Practical sizes remain subject to the capabilities and limitations of the selected framing and glazing system.

Large panels may require additional consideration because glass weight increases rapidly as panel dimensions increase.

Colours and Powder-Coat Finishes

Aluminium windows and doors can be supplied in a broad range of powder-coated finishes depending on the selected system and project requirements.

Colour selection can help coordinate windows with:

  • Roofing
  • Cladding
  • Render
  • Brickwork
  • Aluminium window shrouds
  • Privacy screens
  • Balustrades
  • Other architectural metalwork

Powder-coat warranty coverage is not determined by colour alone.

Applicable coverage depends on the actual coating system selected and applied, powder manufacturer, product range, environmental exposure, proximity to marine or industrial environments where relevant, installation, cleaning and maintenance, and the applicable supplier terms.

How Much Do Double-Glazed Aluminium Windows Cost?

The cost of double-glazed aluminium windows and doors varies according to the complete specification rather than simply the number of glass panes.

Important cost factors include:

  • Window or door dimensions
  • Frame system
  • Standard or thermally broken aluminium
  • Glass type
  • Glass thickness
  • IGU configuration
  • Low-E coatings
  • Laminated or specialised glass
  • Number of opening sashes
  • Door-panel configuration
  • Hardware
  • Screens
  • Powder-coat finish
  • Quantity
  • Delivery
  • Site access
  • Installation scope

For this reason, project-specific quotation is more useful than relying on a generic square-metre price.

Are Double-Glazed Aluminium Windows Worth It?

Double-glazed aluminium windows can be worthwhile where improved comfort, thermal performance, acoustic performance or building efficiency justify the additional specification and cost.

The decision should consider the whole project rather than the window in isolation.

For example, spending more on glazing without considering frame performance, insulation, shading or air leakage may not deliver the same result as a coordinated building-performance strategy.

For premium homes and performance-focused projects, combining appropriate double glazing with a well-selected aluminium framing system can provide a strong balance between architectural design, durability and performance.

Choosing the Right Double-Glazed Aluminium Window System

Before ordering, consider the following:

  1. What performance does the project require?
  2. Does the project require standard or thermally broken framing?
  3. What glass specification has been nominated?
  4. Are there acoustic requirements?
  5. Are there energy-assessment requirements?
  6. What are the opening sizes?
  7. Which windows need ventilation?
  8. What door configurations are required?
  9. What powder-coat finish is specified?
  10. Are screens required?
  11. Are architectural shrouds or screens being coordinated with the windows?
  12. Is supply only or installation required?
  13. Have final dimensions been checked?
  14. Are external drainage and threshold conditions coordinated?

Providing this information early helps create a more accurate quotation and specification.

Supply Only or Supply and Installation

Depending on the project and agreed scope, aluminium windows and doors may be supplied for installation by the builder or other appointed installer, or installation may form part of an accepted EZ Windows scope.

Responsibilities should be clearly established before ordering.

Where installation is undertaken by others, the installer remains responsible for carrying out their work appropriately and coordinating the windows and doors with the surrounding building construction.

Where EZ Windows undertakes installation, the specific inclusions and exclusions should be identified in the accepted quotation or contract.

Compliance and Project Responsibilities

Double-glazed aluminium windows and doors must be selected appropriately for their intended application and project requirements.

EZ Windows manufactures and supplies products according to the approved project information and agreed scope.

Unless separately and expressly engaged to provide a particular professional service, EZ Windows is not acting as the project’s architect, structural engineer, façade engineer, energy assessor, acoustic consultant, waterproofing consultant, building surveyor or certifier.

Project-specific matters including engineering, energy performance, acoustic requirements, building-envelope design and statutory approvals should be determined and approved by the appropriately appointed professionals.

Dimensions and project information must be checked and approved by the responsible party before manufacture.

Warranty and Maintenance

EZ Windows is an AGWA member and generally provides a six-year product guarantee, subject to the applicable written warranty terms, conditions and exclusions.

Where installation is undertaken by EZ Windows as part of an accepted installation scope, the installation warranty is generally one year, subject to the applicable written terms.

Regular maintenance remains important.

Depending on the product and environment, maintenance can include:

  • Cleaning glass
  • Cleaning aluminium surfaces
  • Keeping drainage paths clear
  • Removing debris from sliding tracks
  • Checking operating hardware
  • Cleaning screens
  • Maintaining surrounding sealants where applicable
  • Following applicable powder-coating maintenance requirements

Coastal, marine, industrial and other aggressive environments can require more frequent cleaning and maintenance.

Frequently Asked Questions About Double-Glazed Aluminium Windows and Doors

What are double-glazed aluminium windows?

Double-glazed aluminium windows use two panes of glass separated by a sealed cavity and installed within an aluminium window frame.

The complete performance depends on both the glazing unit and framing system.

Are double-glazed aluminium windows better than single glazing?

Double glazing generally offers greater thermal-performance potential than comparable basic single glazing, but actual performance depends on the complete window specification.

Are aluminium frames suitable for double glazing?

Yes. Aluminium framing systems can be designed to accommodate insulated glass units, provided the selected system is suitable for the required glazing configuration, dimensions and project conditions.

Is thermally broken aluminium necessary with double glazing?

Not for every project.

A thermally broken frame can significantly change the thermal characteristics of an aluminium window, but whether it is required depends on the project’s energy assessment, climate, building design and performance objectives.

Does double glazing keep a house cooler?

Double glazing can help reduce heat transfer, but summer performance also depends on glass selection, solar exposure, orientation, shading, frame performance and the overall building design.

Does double glazing keep a house warmer?

Double glazing can reduce heat loss through the glazed component of a window compared with basic single glazing, helping support improved winter comfort when incorporated into an appropriately designed building.

Does double glazing reduce noise?

It can.

The amount of noise reduction depends on the glass configuration, frame, seals, opening type, installation and surrounding building construction.

Are double-glazed windows soundproof?

No. Double glazing should not automatically be described as soundproof.

Projects with significant acoustic requirements should use an appropriate acoustic specification.

Does double glazing stop condensation?

Not completely.

It can reduce condensation risk on internal glass surfaces under some conditions, but condensation is influenced by humidity, temperature, ventilation, frame performance and overall building design.

Can sliding doors be double glazed?

Yes, provided the selected aluminium sliding-door system is designed to accommodate the required insulated glass units and resulting panel weights.

Can stacker doors be double glazed?

Yes. Suitable stacker-door systems can accommodate double glazing subject to system, panel-size, glass and hardware limitations.

Can bifold doors use double glazing?

Yes, where the selected bifold system is designed for the specified glazing and panel weights.

Can double glazing use Low-E glass?

Yes. Low-E glass can form part of an insulated glass unit where appropriate for the project’s required thermal and solar performance.

Can I order custom-size double-glazed aluminium windows?

Yes. Custom aluminium windows can be manufactured in many project-specific dimensions and configurations, subject to the limitations of the selected frame, glass, hardware and project conditions.

Can double-glazed windows be used for window replacement?

Yes, but existing openings and surrounding construction should be assessed to determine the appropriate replacement solution.

Are double-glazed aluminium windows low maintenance?

Aluminium framing is relatively low maintenance, but windows and doors still require appropriate cleaning and maintenance of glass, tracks, drainage paths, hardware, screens, seals and finishes.

How long do double-glazed aluminium windows take to manufacture?

Lead times vary according to system, glass specification, quantity, finish, supplier capacity and project requirements.

Current lead time should therefore be confirmed when requesting a quotation or placing an order.

What is the best double-glazed aluminium window?

There is no single best system for every project.

The appropriate system depends on the required thermal performance, acoustics, opening configuration, dimensions, architectural appearance, budget and project conditions.

Request a Quote for Double-Glazed Aluminium Windows and Doors

If you are planning a new home, renovation, replacement-window project, commercial development or architectural building, EZ Windows can quote double-glazed aluminium windows and doors according to your project requirements.

For the most accurate quotation, provide as much information as possible, including:

  • Architectural plans
  • Window and door schedule
  • Approximate or confirmed dimensions
  • Required configurations
  • Glass specification
  • Energy requirements where applicable
  • Powder-coat colour
  • Screens
  • Project location
  • Required delivery timeframe
  • Supply-only or installation requirements

Our objective is to make specifying, pricing and ordering custom aluminium windows and doors simpler for homeowners, builders, architects and project teams.

EZ Windows — Architectural precision, designed to perform.

Do It Easy.