Driven by a range of factors including regulatory changes, the sustainability drive, and concerns around bushfires, the residential window market is not what it once was.
The Australian residential window market has matured.
“Over the last 50 years, windows were mostly made to be cheap, but now there is a push for higher performing windows and doors which enhance all the improvements made in the rest of the building envelope,” says Tony Paarhammer, Managing Director of Paarhammer Windows.
Driven by the sustainability imperative, the need to change has been accepted by not just architects and other industry professionals but by consumers.
“We are seeing a far better educated residential customer compared to the same time five years ago, which is really encouraging,” says Vince Bianchini, Director of Sales and Marketing at Cooling Brothers.
“We’re now working with customers who are proactively requesting energy efficient and acoustic glazing for their new or retrospective home build; and have already educated themselves with the basics. They’re open to high performance options.”
As John Toskas, Managing Director at NICCO Timber Windows & Doors notes, this evolution has extended to the regulatory environment.
“Recent changes to federal and state building policies and codes have put a spotlight on the drive towards sustainable building practices in Australia, and windows play an important role in meeting the new standards,” he says.
“Changes to the National Construction Code (NCC) for example, mandate new homes and renovations costing more than $50,000 must reach a 7-star rating on the Building Sustainability Index (BASIX) as opposed to 5.5. Windows contribute significantly to the building envelope and can similarly help or hinder achieving a compliant outcome.”
That said, what are some of the latest window products to hit the Australian residential market and what was the thinking behind their introduction? Here is a selection of some of the best.
Image: Alpsec
Soft coat Low-E glass
Bianchini says that, in terms of introducing new products, Cooling Brothers often takes cues from the European market.
“Soft coat Low-E glass, and 4SG warm edge spacer technology have been widely adopted in European insulated glass units (IGUs) for some time, and it is where we see the Australian residential market heading more broadly in the long term,” he says.
The Insulcool Ultra Series, which is built around the Kommerling 4SG warm edge spacer, is Cooling Brothers’ soft coat performance range.
The Kommerling 4SG warm edge spacer is a European thermoplastic spacer that eliminates the metal thermal bridge and is extruded directly onto the glass for unbeatable long-term gas impermeability and optimal insulation values.
“For residential projects, Ultra Light E offers homeowners an entry point to enjoy the benefits of a commercial soft coat combined with a 4SG spacer, without having to resort to a commercial product,” says Bianchini. “Ultra Light E is designed in Australia, specifically for the Australian residential market and can achieve a U value as low as 1.39, and SHGC of 0.36.”
Another low-E glass product is set to become a game changer in solar performance and passive design, according to Nic Reid from Glassworks Sales and Marketing.
Until now, triple-silver low-E glass was the ultimate performer, achieving a Solar Heat Gain Coefficient (SHGC) of around 0.27 and a Visible Light Transmittance (VLT) of around 63%.
"With a fourth layer of silver, residential and commercial buildings can now enjoy additional solar control without having to resort to a tinted glass or heavy triple glazed unit", she adds.
LoĒ-452 + Neat from Glassworks claims to achieve an SHGC of 0.22 balanced with a Visible Light Transmittance (VLT) of 50%. This makes the Light to Solar Gain ratio (LSG) around 2.3, meaning it transmits more light than solar heat, unlike uncoated glass.
“The exterior appearance of LoĒ-452 + Neat will be clear with a subtle grey tinge and clear from the inside looking out, with 99% UV protection. The new variant joins our popular LoĒ-366 + Neat triple silver coated glass which is classified as 'neutral' in colour" says Reid.
According to Glassworks literature, LoĒ-452 + Neat will “provide the perfect solar solution for large facades in commercial and high-end residential projects of western elevations, especially in warm or mixed climates”.
What's more, says Reid, “the 'Neat' denotes a bonus invisible titanium dioxide that comes standard on the outer layer, a patented technology which works to keep the surface naturally cleaner for longer.”
Double glazed louvre system
Available now from Breezway, the Altair Double Glazed Iglu System is the first Australian designed double glazed louvre on the market. Developed in response to the above-mentioned changes to the NCC, this high-performance system integrates the advantages of double glazing along with the ventilation properties inherent in louvre windows.
Image: Breezaway
Constructed from robust materials, each Altair Iglu Louvre blade is assembled with two layers of 5mm Low-e toughened glass and a 12mm argon gas filled space. The blades do not have thermally comprising aluminium framing. Instead, they are capped at the top and bottom by rubber blade-to-blade seals, embedded into the IGU sealant.
There is a clean ceramic print running along the perimeter of each blade to conceal the IGU spacer, while still drawing the eye through to the view outside; and the design of the blades allows for the internal glazing layer to be retained by the clip, while the outer layer of the glazing finishes flush with the surface of the clip.
According to the company, compared to monolithic 6mm Clear Low E glass in Breezway aluminium and generic timber framing, the IGLU System improves Uw values by 18% and 24%, respectively. This enhancement in thermal performance, with WERS ratings as low as Uw2.6, maintains ventilation properties.
Framing choices - Accoya wood
According to Toskas, while the focus is often on glass selection to provide better thermal and energy efficiency, it’s also important to consider window framing materials. In his opinion, on these terms, timber is the best option for residential applications.
“Because timber is a natural thermal insulator – thanks to the air pockets within its cellular structure – the thermal insulation of timber is 350 times better than steel and 2000 times better than aluminium,” he says.
“Timber also has low embodied energy compared with other popular building materials…By way of comparison, the embodied energy of air-dried sawn hardwood is 0.5 MJ per kg versus aluminium which is…170.0 MJ per kg.”
Toskas sees Accoya wood, which is manufactured by modifying wood sourced from well-managed sustainable forests through acetylation and without the introduction of toxins, as the way of the future.
He says that by choosing an Accoya window with the right glazing combination, it is possible to end up with a high-performance window solution that assists in reducing energy consumption and is also sustainable in timber-resource sense.
Embedded framing technology
Comfortedge, a product designed and manufactured by Architectural Window Systems, is another option. Unlike thermally broken framing systems, the product features a new embedded framing technology, leveraging the timber reveal to act as a natural, thermal insulator against indoor and outdoor temperature variations using a 100% aluminium window or door frame.
Image: AWS
This design involves fewer extrusion profiles, which reduces the need for manufacturing processes and tools, and allows the use of aluminium framing rather than thermally broken frames.
According to the company, Comfortedge Uw Values can even outperform thermally broken framing systems in many residential applications and offers specifiers design freedom not often achievable with alternatives.
The product was developed as an affordable, high-performance, energy-efficient window and door framing system for use across a broad range of residential housing applications. While an optimised design for manufacturing is ideal for affordable housing, the engineering in the system still provides the strength and weather performance, together with a minimalised design aesthetic, to span 3000mm high sliding doors and large window openings in line with the demands of architectural housing design.
These features ensure that Comfortedge is a versatile option for new homes, in accordance with 7 Star Energy Ratings.
uPVC
In terms of window framing, Unplasticized Polyvinyl Chloride (uPVC) is another option, which according to BINQ, is only just beginning to make its presence felt here in Australia.
Having recently imported a highly automated uPVC production line from Europe and opened up an additional manufacturing facility, the company is in a good position to comment on the material. Citing a case study conducted on its behalf by an independent environmental consultant, BINQ claims that all other relevant variables being equal, the installation of its products containing uPVC increased the energy ratings of all the homes in which they were installed.
On top of that, considering the importance of factors like price and maintenance costs, the company claims the material can turn out to be 50% cheaper than timber and is completely maintenance free.
Available in not just blacks, greys, and whites, but also options that are designed to resemble real timber, these uPVC profiles feature a slimline design which minimises the amount of framing material required and maximises the amount of glass, leaving rooms full of light and with an enhanced view of the outdoors.
Windows & livable housing design
In 2022, the NCC was also changed to include new requirements for ‘Livable Housing Design’, which refers to homes that are designed to make them easier to use and more adaptable to the changing needs of occupants.
In addition to reducing steps where possible, providing more space in bathrooms, and so on, this also has implications for things like doorway widths.
Alspec has made its latest products, including the Proglide Ultraflat Sliding Door, the Altitude Ultraflat Sliding Door, and the Hawkesbury Top Hung Sliding Door, in response to these regulations and more broadly to the growing emphasis on livable housing.
Crafted with precision, the Proglide Ultraflat Sliding Door features a weather-resistant, wheelchair-compliant sill in accordance with AS1428.1 standards, ensuring inclusivity without sacrificing performance or style. Elevating the concept of sliding doors, it harmonises innovative design with practical functionality, offering a solution that exceeds expectations in both form and purpose.
Then, the Altitude Ultraflat Sliding Door, which is also designed with AS1428.1 in mind, provides a touch of elegance in a more compact form. Tailored with precision, this door is recommended for contemporary apartments where every detail matters.
And finally, the Hawkesbury Top Hung Sliding Door not only provides the freedom to create large, expansive openings but also comes equipped with a weather-resistant and wheelchair-compliant sill, seamlessly combining form and function.
Composite window & door products
According to Tony Paarhammer of Paarhammer Windows, Composite window and door products are increasing in popularity because they provide the “best of both worlds” – the warmth and energy efficiency of timber on the inside with low-maintenance aluminium on the outside.
“This also provides the option of a clear timber finish on the inside for the light or blond colour, which is fashionable now, often combined with black handles,” says Paarhammer. “European hardware is becoming more mainstream, especially for lift-slide sliding doors.”
Asked for examples, Paarhammer mentioned his company’s Wood-Alu, a range of composite windows and doors with highest energy efficiency, plantation grown hardwood timber on the inside and powder-coated aluminium on the outside for low maintenance.
On top of that, for many years now Paarhammer has also made bushfire safe windows and doors up to and including BAL-FZ, fully tested, approved and compliant.
All Paarhammer products have full documentation for compliance to all relevant AS (Australian Standards), which is extremely important for building professionals as it provides peace of mind. Tests include ultimate strength tests, deflection tests, and of course energy efficiency ratings. Paarhammer product ranges are also listed on WERS (Window Energy Rating Scheme).
A marriage of timber & aluminium
Along similar lines, Miglas Aliclad frame system effectively combines the advantages of timber and aluminium. A double-glazed system that is manufactured in Australia, it can be relied upon to provide comfort and protection all year round, with the added benefit of a wide choice of styles, sizes, and colours.
Image: Miglas
According to the company, beyond the fact that Aliclad meets the highest standards in terms of thermal efficiency, low maintenance requirements and acoustic performance, another point worth noting is that it is designed, engineered, manufactured, and distributed solely in Australia.
Miglas sources over 90% of its componentry from Australia, while its hardware is sourced from Germany, Italy, and the US. The internal timber used to manufacture Aliclad is Victorian Ash Hardwood, which is sourced under a “Responsible Wood” Initiatives, while the aluminium in the products is sourced under and Aluminium Stewardship initiative that reduces carbon output by up to 75%.
Having been available for more than 25 years now, it appears the market has finally caught up with Aliclad. Like the various other products mentioned above, it is right at home in these times of well-informed consumers, ambitious regulatory changes, and the mainstream acceptance of sustainable development.
Main Image courtesy: Paarhammer. This image shows fixed shaped windows, lift-slide sliding stacker doors, and a corner lift-slide sliding door in the Bushfire Safe Range, BAL-FZ (Bushfire Attack Level - Flame Zone). Architect: Ellen Woolley Builder: Davis Builders
SUPPLIERS
Alspec
Miglas
Architectural Window Systems
Breezway
Paarhammer Windows & Doors
BINQ
Nicco Timber Windows & Doors
Cooling Brothers