What is Double Glazing?
Double glazing consists of two panels of glass units separated by a layer of air or argon gas and then sealed. Argon gas is known to create a more effective insulation barrier than air, greatly reducing both heat flow and thermal conductivity through the glass.
Jason Windows uses argon gas in all Jason Double Glazed Windows & Doors.
Benefits & Considerations
The benefits of double glazing:
- Excellent insulation performance, greatly reducing energy costs. Low-E glass can be used in a double-glazed unit to further increase energy efficiency.
- Double glazing can minimise noise if the right glass combinations are selected. It is better suited to medium to high frequency noises, such as human voices and dogs barking. For low frequency noises such as aeroplanes and road traffic, consider laminated glass, either on its own or within a double-glazed unit.
- Reduces condensation, which can occur when warm humid air condenses on the relatively cold glass surface.
- Reduces the need for insulation provided by window coverings. Where privacy is of no concern, curtains or blinds may be unnecessary to control temperature comfort levels.
For specific noise problems, consider consulting an acoustic engineer for the right solution. An acoustic engineer will assess the levels and types of noises causing concern and specify the acoustic performance requirements to suit your needs.
The Australian Standards & Building Regulations will determine some glass choices within your home. For example, as a rule, you must use Grade A safety glass in all glass doors. Either double glazed toughened safety glass or double glazed laminated safety glass could be selected for a door requiring Grade A safety glass.
Double glazing is expensive compared to other glass types. However, you don’t have to opt for it throughout your entire home. Consider choosing more cost-effective glass options in less-used spaces such as bathrooms and the laundry.
If you are choosing double glazing for noise reduction alone, then laminated glass will be a more cost-effective solution.
If you want to select Low-E glass for your double-glazed unit, the risk of thermal stress should be considered.
A Jason Windows product specialist can offer you glass selection assistance when you book a consultation in one of our showrooms.
Energy Efficiency Claims
You may have seen or heard varying and sometimes confusing claims guaranteeing energy savings from different glazing providers. The Australian Glass and Window Association reports as much as 49% of the heat lost during winter and as much as 87% of the heat gained during summer can come from your home’s windows.* This information comes from a trusted source and can be used as a general guide.
However another trusted source, the Australian Government website YourHome has published the data respresented in the above image as general. They further outline why the impact of glazing on your home’s energy efficiency is complex to calculate due to varying contributing factors, including:
- Climatic conditions — temperature, humidity, sunshine and wind
- Building design — the orientation, form and layout of your home
- Building materials — the amount of thermal mass and insulation
- Size and location of windows and shading
- Thermal properties of glazing systems
Your home’s energy-efficient performance is the result of all of the above and will therefore be different for every home.
*Testing results published by the Australian Glass and Window Association , based on an average house containing 8% area of glazing in the entire building fabric.
Thermal Performance Testing
You can seek an independent energy efficiency assessment of your new home or renovation through a thermal performance assessment provider. Based on your plans or existing home, a qualified assessor will determine your home’s ability or potential to maintain a comfortable temperature all year round.
Thermal performance assessments are best carried out before finalising your plans and submitting a development application. The assessor will provide you with a final list of building materials required to achieve your desired results for discussion with your builder.
Reputable thermal performance service providers can be sourced from the Australian Building Sustainability Association (ABSA).
A minimum space of 12mm is recommended by the AGWA for optimum thermal performance. Jason double-glazed units are up to 24mm overall. For example, depending on your requirements, your Jason double glazing may be:
- 6mm glass | 12mm argon gas space | 6mm glass = 24mm
- 6mm glass | 8mm argon gas space | 10mm glass = 24mm
Generally, the bigger the argon gas space, the better the insulation performance. Glass thickness is determined by the overall size of the glass panel, and thermal or acoustic performance requirements.
Each of the two glass panels in a double-glazed window or door can be specified to suit your requirements for different areas of your home.
Here are some common combinations:
Double Glazing Option:
- Double-glazed unit with annealed glass
Double Glazing Options:
- Double-glazed unit with laminated glass, or
- Double-glazed unit with laminated acoustic glass
Double Glazing Options:
- Double-glazed unit with Low-E glass, or
- Double-glazed unit with Low-E toned glass
Double Glazing Option:
- Double-glazed unit with Low-E laminated glass
There are many more options available. A Jason Windows product specialist can help you match the most effective glazing solution with every room in your home. Book a consultation in one of our showrooms.