Insulated Glass Units (IGU’s) Are They Fit for Purpose?
IGU’s are the manufactured glass unit that form the glass component in a double-glazed window.
Energy compliance of buildings becomes more important as Australia moves towards efficient use of electricity, and insulating the entire house becomes paramount. Windows and doors form a large part of most building envelopes; therefore, insulation is important.
Normal clear monolithic glass offers very little insulation value, allowing heat or cold weather to affect the internal environment of a building, requiring air-conditioning, or heating to ensure comfort levels inside the building. Therefore, driving up energy usage.
“How do you know that you have compliant IGU’s that will offer long term clear vision and good insulation value?”
Azuma Design type tests IGU’s to the long-term requirements of AS4666 “Insulating Glass Units”, which ensures good manufacturing practices have been used to produce good IGU’s that will last for many years, providing great insulation.
The sample IGU’s are placed in an accelerated weathering cabinet for 15 weeks.
Azuma then tests the moisture content of products before weathering and post weathering of the samples provided for testing.
If the moisture content has increased significantly post testing, this will result in a failure, also indicating to the manufacturer that they need to correct their manufacturing practices before they are issued a compliance certificate.
Great IGU’s need to have both their primary and secondary seals applied correctly for longevity ensuring no moisture can penetrate to the internal gap between the windows.
If these seals fail moisture will penetrate, ruining the integrity of the IGU, decreasing the insulation value of the IGU and possibly the visual aspect allowing fogging in the internal gap.
A lot of IGU’s have argon gas that fills in the gap between the two glass panels, which provides for a 10 to 15% insulation improvement.
If the seals fail this gas escapes, reducing the insulation value the IGU provides, meaning the building envelope is compromised.
Azuma’s testing capabilities ensures the IGU’s presented for type testing have been manufactured correctly.
This should ensure the manufacturing of all IGU’s from a supplier are of great quality.
If the IGU’s pass the long-term testing requirements of AS4666, then the product is fit for purpose and installation in your building.
This means that the product then is ideal to meet the comfort levels we expect over the useful life expectancy, while installed in the building.
Manufacturers are required to type test there IGU’s every 2 years when purchasing double glazed windows, ensure that the product purchase has been accredited.