Bigger is better right now when it comes to windows and doors and in the commercial sector, according to National Marketing and Business Development Manager at Australian Glass Group, Michael Ward.

Ward says this is not only for those inside to appreciate the views outside, but also for those passing by to see the “engineering feats and activity within”.

It may sound simple enough to execute, but Ward points out that these larger windows and doors can cause issues with meeting the strict new minimum energy efficiency requirements in the revised National Construction Code (NCC).

“This translates to lower Solar Heat Gain Coefficient (SHGC) and lower U-Values in the glazing,” he says.

“Overlay this to the trend of larger glazing and you see a conflict that can only be satisfied by either conceding and reducing your window-to-wall ratio or using higher performing glazing.”

If you select higher performing glazing, Ward notes it is important to make sure you don’t forget about the comfort and wellbeing of those working in these commercial buildings.

“You can tick the boxes of a very low SHGC with a dark grey glass, however your building is now black with 6% visible light coming in,” he said.

The trend in glass therefore is high performance but maintaining neutrality in aesthetics and high visible light. To solve this Australian Glass Group has developed Insulglass LowE Max, one of the highest performing triple silver soft coat low-e’s in the world market.

“It is stocked and made into double glazed units right here in Australia – NSW, Victoria and Tasmania,” he explained.

The product has very low SHGC, very low U-values and yet 66% visible light transmission with a neutral look.

“Excellent colour renditions for looking through the glass, so the blue sky still looks blue, and the green grass is still green,” Ward says.

“95% UV blockage to help protect your furniture, timber floors, carpets and artwork from fading,” he says.

The product is available in both 6mm and 8mm thick to be able to maximise window sizes without compromising performance. It also virtually eliminates the possibility for condensation to form on the inside of the glass.

When speaking to Viridian glass, very similar challenges were echoed about adhering to the new NCC guidelines while trying to meet commercial client’s desires to have large windows that let plenty of natural light in.

“The challenge is striking the right balance between natural daylight and thermal performance of the building envelope,” National Markets and Industry Manager Anthony Gunther says.

“Spectrally selective low e double glazing products are the game changer here,” he says.

“And we need to start moving the needle to specify these products here in Australia on a larger scale for better performing sustainable buildings”.

To assist in identifying the best glass options, Viridian has adopted a new term called Selectivity. Glass Selectivity is an index that reports the relationship between visible light transmission and solar heat gain, it is measured as an index (S = Vt/g) with a high selectivity more preferable in modern building design. High selective glasses, generally above 1.8, offer exceptional performance.

Viridian has three key spectrally selective low e double glazing products available to support designers to meet these new challenges in glazing specification.

The first is LightBridge next which takes the current LightBridge product and offers next generation benefits. It contains improved thermal edge performance due to its non-conductive spacer. This spacer minimises energy loss and there is also a greater reduction in the potential for condensation to form at the edge.

LightBridge next also contains a specially formulated glass to dampen noise, providing enhanced sound insulation performance.

Secondly, there is PerformaTech, which balances high levels of light transmission with very low levels of solar heat gain to provide a brighter and more comfortable space.The range uses a high-performance coating that restricts UV and infrared radiation from passing through but importantly provides exceptional levels of natural appearance in.

Lastly, Viridian’s ClimaTech is a limited range of clear or toned double-glazed units for applications which require a better performing window glass. ClimaTech uses two pieces of glass, one coated with a spectrally controlled low e coating and the other an ordinary clear or toned glass.  

“These product solutions allow designers and specifiers to strike a perfect balance for commercial and multi-use buildings,” Saccaro says.

Viridian’s PerformaTech glass was folded, origami style into towering walls of transparency and reflection on the new Geelong Library and Heritage Centre. Viridian’s PerformaTech glass was chosen for the $45 million project by ARM Architecture thanks to its high lustre, crisp light transmission, solar control and thermal insulation.

Whilst designing the unique sphere-shaped landmark building, ARM architect, Wayne Sanderson engaged Viridian to help calculate how much glass to include, the amount of the facade that is vision glazing and how it should be treated.

“The technical input from Viridian is vital and their level of expertise and service is a contributing factor as to why we bring them on board,” he says.

He says the extent of glazing and its performance was vital to the build, going on to explain that the zigzag form of the glazing was a conscious decision to assist with the environmental performance.

“By rotating the glazing away from the west, it faces the north-west and south west, the glazing system is more efficient,” he says.

Director of EBSA David Auret also highlighted the impact that the NCC changes have had on his client’s choices.

“The changes to the code have definitely impacted the use of single glazing in commercial projects and this has been very evident by the increased demand for thermally broken double glazed louvre systems,” he says.

“Even though EBSA has offered these systems since 2012, it is only in the last few years that the need to achieve excellent thermal performance has driven mainstream interest in high-performance double-glazed louvres,” he says.

One popular choice for his clients is the thermally broken framed double-glazed louvre SLS BT90. It is certified to AS2047 at a width of 1740mm wide making it able to span substantially wider openings than conventional glass louvre systems.

“The stand-out features of this product is that it is fully compliant for use in air-conditioned buildings passing both the positive and negative air leakage tests and it achieves U values below 2.5 because of its superior thermally broken frame design,” he says.

The system is not limited to double glazing and in fact with triple glazing it is possible to achieve acoustic values as high as RW42 and even lower U values.

Another top offering is the MP2 Louvres which David believes set the benchmark for louvre systems worldwide.

“Tested to AS2047 it achieves resistance to water ratings as high as 1000 pascals and performs as well as some fixed glazing systems in terms of air leakage. In one test it actually recorded no air leakage at 75 pascals,” he says.

“It is available in both a framed or, a semi frameless version. MP2 is used where facade performance is critical”.

EBSA supplied and installed an MP2 fully framed, double glazed louvre system and CPS-M control panel at Barrack Place, an A-Grade office building in Sydney CBD.

Barrack Place was recently named as a Property Council of Australia 2020 Innovation & Excellence Awards Finalist in the ‘Best Office Development’ and the ‘Best Sustainable Development – New Buildings’ categories.

It is also the first building in Australia to receive a WELL Certificate Platinum rating from the International WELL Building Institute. Additionally, the office building has also achieved a Green Star Office Design V3 Certification from the Green Building Council of Australia.

EBSA said they were thrilled to be involved with the “outstanding project” which achieved functionality for both smoke and natural ventilation.

“The SLS BT90 and MP2 double glazed systems simply outperform any single glazed louvre in terms of thermal and acoustic performance, they are also able to span significantly wider than traditional glass louvre systems,” he says.

“Both products allow for very large format louvre blades with heights of around 450mm providing a significantly more pleasing aesthetic than other systems,” he concluded.

Another increasing request from commercial clients searching for the right windows and doors for their build is the need for level access thresholds.

This was pointed out by National Specification Manager at Alspec Ross Baynham who says, “whilst we are finding that many buildings are being built with universal access in mind, allowing wheelchair access, we also believe there is an aesthetic appeal as well”.

Alspec has a number of products that provide a level access threshold into a building with their most popular product in this category the ProGlide High Performance Sliding Door. Some of the benefits of the door include the fact it can have have door panels up to 3150mm high and 2250mm wide, it can provide up to 700 pascals for water penetration and it has the option for an AS1428.1 compliant sill in the ProGlide UltraFlat option.

The ProGlide High Performance Sliding Door was chosen by the designers of premium retirement living complex Anglicare Woolooware Shores in Taren Point, NSW. The ProGlide Sliding Doors were chosen with the flush sill option, allowing a smooth transition from indoor to outdoor areas to assist residents of all mobility levels.

To provide secure and protected access to balconies and courtyards, Alspec’s custom Aluminium extrusion abilities came to the fore, creating the new sliding door and flyscreen combination. A custom extrusion is a cost-effective way to create complex cross sections to suit specific uses which are then easily assembled with other building components. The flyscreen framing was incorporated into a single frame directly alongside the ProGlide High Performance sliding door,

Alspec’s Hawkesbury Commercial Multi-Fold Doors and Swan Evo 45mm Double Glazed Commercial Doors are also options for achieving universal access.

Both these doors can be seen in action at Rydges Gold Coast Airport in Queensland where easy access was needed for the ground floor outdoor amenities. The multi-fold doors operate smoothly using tyred floor guides along concealed channels. This enables a wide opening to connect the poolside area to the adjacent restaurant and bar, creating an indoor-outdoor relaxing leisure space.

The Swan Evo doors, used where hinged or pivoted doors were required, offer centre pocket glazing and hard-wearing componentry, making them ideal for the hotel and hospitality environments from both security and durability perspectives.

Commercial window and door design has changed a lot in the past year thanks to the increased stringency of the energy efficiency requirements laid out in the National Construction Code.

This coupled with a trend towards large windows and doors mean high-thermal performing -products have never been so important to the market. When it comes to doors, more consideration is also being taken about universal access, which slots in nicely with the trend for seamlessly flowing indoor outdoor spaces.

Caption: EBSA supplied and installed an MP2 fully framed, double glazed louvre system and CPS-M control panel at Barrack Place, an A-Grade office building in Sydney CBD.

Suppliers:

Australian Glass Group  

Viridian 

 EBSA 

Alspec