Empowering glass
Transforming windows and glass doors into high performance units with window film.
If the essence of good building design is found in blending artistic expression with practical insight, then windows pose a challenge and opportunity.
While glass is essential to fulfilling almost every design principle, its very nature makes it worthy of careful consideration. From an energy perspective, the unflattering name for windows as ‘thermal holes’ underscores the point.
Design control is gained through window treatments, like film, which improve the performance of glass by countering its drawbacks. Selecting the right film allows for the potential of a window to be reached without compromising energy efficiency, comfort, safety and security or the functionality of a space.
A place of wellbeing
Natural light, ventilation and a connection with the environment sit at the forefront of design for wellbeing.
According to Queensland Health:
“Exposure to natural light is essential for good mental health. Research has found that workers in offices with windows received more natural light and had better sleep quality, higher physical activity levels, and lower stress levels than workers in windowless offices.”
Film can let in the light while reducing heat and UV, and in doing so, prolong the health benefits of exposure to natural lighting and a maintained view to the outdoors.
Ally Cronan, Window Film Association of Australia and New Zealand (WFAANZ) President, comments, “Improving a window’s ability to reject or retain heat, reduce glare and almost entirely block UV rays gives the building owner more control over the space.
“Not having to draw the curtains or blinds at certain times in the day means the space can stay awash in natural lighting for longer periods of time.”
Spectrally selective films - light without heat
Films that block the part of the energy spectrum that is not desirable – heat, while allowing the transmission of the part of the energy spectrum that is desirable – light, are called spectrally selective window films.
Retrofitting for efficiency
In a typical residential building where glazing forms only 8% of the building envelope, it can be responsible for up to 87% of envelope heat gain and 49% of heat loss. That is why in the harsh and diverse Australian climate, a glazing assessment is one of the first steps when reviewing the energy efficiency and comfort of a building.
One of the most distinctive traits of window film is its ability to regulate solar energy passing through glass. Up to 85% total solar energy, 99% UV radiation and 95% glare can be blocked by window film.
WERS For Film
Endorsed by the federal government, WERS For Film is a fair, rigorous and credible system for testing the performance claims of different window films. Conforming to the alternative solution path for energy efficiency within the National Construction Code, WERS for Film incorporates:
- Ratings: Film manufacturers have films rated and labelled by an independent laboratory for their annual energy impact on a whole house, in any climate of Australia.
- Accreditation: Window film installers become WERS For Film accredited by completing a training program managed by WFAANZ.
- Selection: end users can select from a list of accredited installers who work with them to select the appropriate WERS rated film.
- Certificates: a WERS For Film certificate is issued at the completion of the installation, forming part of that building’s energy efficiency documentation.
Your Home: the Australian government’s guide to environmentally sustainable homes
“Applied to existing glass, some window films can halve the overall SHGC of the window by absorbing and/or reflecting solar radiation. This can be particularly beneficial in hotter climates where cooling is the main concern, or on east and west elevations directly exposed to long periods of sunshine.”
Pathway to decarbonisation
A building’s electricity and gas consumption is explicitly linked to the performance of its glazing systems. As a retrofit product, window film can upgrade the existing built environment to help Australia and New Zealand meet 2050 decarbonisation goals.
Glass can take up to a million years to breakdown in landfill*, so the sustainability benefits of enhancing existing windows rather than replacing them cannot be overstated.
Space optimisation
The ways a home is traditionally ‘lived in’ and what a homeowner needs from their space changed during the pandemic. Rooms were used at different times of the day, for different reasons and with different occupants.
During that time and since, the nature of window film enquiries have changed. Daytime privacy has become a top driver of window film, due in part to the proliferation of home offices. Controlling glare on computer, laptop, TV and device screens is another sought-after function of film, to optimise the usability of a room and the flexibility of its layout.
Layer of protection
Fading of timber floors, furniture, artworks, upholstery, etc. is the result of direct exposure to sunlight.
In reducing up to 85% total solar energy and 99% UV, window film significantly reduces two of the worst offenders when it comes to fading. However it should be noted that no glazing or film product will entirely eradicate fading.
Glass presents a safety risk in terms of broken windows, and a security risk in terms of easy ingress for thieves.
Safety and security window films that are thicker than normal film and have a high bond-strength adhesive effectively hold glass shards together in the event of breakage.
Films available from WFAANZ distributor members that have been tested for compliance can bring glazing up to meet Grade A safety glass requirements in AS1288-2021 Section 5, Criteria for Human Impact.
Fading
The rule of thumb breakdown is that fading is caused by 40% UV light, 25% visible light, 25% heat and 10% other factors like humidity, poor dye stability (fabrics), artificial lighting, chemical vapours, etc.
About window film
Window film is an ultra-thin polyester-based material that can be professionally installed on most glass surfaces. It is retrofit to existing windows, usually on the interior surface of the glass, providing site-specific benefits at a fraction of the cost of new glazing.
Modern films are manufactured in many different shades, colours and constructions covering everything from very dark to nearly invisible. This gives each film unique performance characteristics that impact its suitability on different glass types. WFAANZ window film installers are trained to match the right film to glass.
About WFAANZ
As the peak body for the Trans-Tasman window film industry, WFAANZ represents close to 200 installers, manufacturers and distributors of window film, serving as a unified voice advocating for the benefits of window film technology and the interests of our members.
As an independent, non-profit association, WFAANZ sets performance guidelines for its members, with a strict code of ethics and compliance with all relevant Australian and New Zealand regulations and standards.
Contact info@wfaanz.org.au for more information.
