Double glazing, or the creation of an Insulated Glass Unit (IGU), involves spacing two or more lites of glass apart and hermetically sealing them to form a single unit with an air gap. This gap enhances the thermal performance of the glass, making double glazed windows and double glazed doors a preferred choice in architectural applications. Typically, an IGU consists of two glass panels, although triple glazing is used in extremely cold climates. These units, manufactured in Sydney, can be framed in a sash or frame to create highly energy efficient windows.

The insulative properties come from the air space between the glass layers, which can be filled with air or inert gases like argon or krypton for improved performance. Desiccants are used to prevent condensation and enhance insulation. Occasionally, air is removed to create a partial vacuum, drastically reducing heat transfer through convection and conduction. This method is known as evacuated glazing. The air gap typically ranges from 8mm to 22mm, with 16mm being the optimal thickness recommended.

Spacers maintain the separation of the glass panes and house the desiccant, which absorbs moisture. Silicone sealant provides structural strength, while butyl sealant serves as the primary defense for the hermetic seal. Utilizing insulated window and door products, such as uPVC double glazed windows, offers numerous benefits, including lower energy costs, improved comfort, reduced condensation, and less fading of interior furnishings.

In summer, double glazed windows and doors with a low solar heat gain coefficient reduce the amount of heat entering the home, enhancing comfort and decreasing cooling energy requirements. During cooler seasons, these products create warmer interior glass surfaces, reducing frost and condensation. They also protect against UV rays, which cause fading and degradation of materials like carpets, curtains, and artwork.

A film or coating applied to the glass surface can further enhance heat and sound insulation. Made of polyester or metal, this film offers a reflective appearance and a one-way mirror effect, improving both insulation and safety in case of breakage. Secondary glazing, a cost-effective alternative, involves adding a layer of glazing inside the existing window for extra insulation.

Key Performance Requirements:

1. Thermal Insulation: The primary function of IGUs is to reduce thermal heat transfer from the outside. Effectiveness depends on the dryness of the air inside the IGU and the quality of the hermetic seal. Dry air is a poor heat conductor, and the air gap significantly reduces heat conduction through the glass.

2. Structural Strength: IGUs are heavy and must maintain strength, especially in structural glazing applications. The type and quality of spacers, sealants, and spacer joints are crucial for maintaining this strength.

3. Fogging Protection: Properly manufactured IGUs provide better protection against fogging than single panes of glass. However, poor quality control can lead to fogging issues.

Key Quality Areas:

1. Desiccant Quality: Using the correct type and quantity of desiccant is crucial for absorbing moisture and maintaining air dryness within the IGU. Contact with ambient air during filling must be avoided.

2. Spacer Joints: Ideally, spacers should have no joints. Automatically bent spacers with a single side joint are preferred over multiple corner joints for better structural strength.

3. Controlled Environment: IGUs should be manufactured in a controlled environment to prevent moisture absorption and dust entry.

4. Sealant Quantity: The secondary sealant provides rigidity, and its quantity must be appropriate for the IGU size.

5. Equipment: Proper manufacturing equipment is essential for producing high-quality IGUs that perform well over their lifecycle.

Spacer Thickness: Our IGUs are available in various thicknesses (6, 8, 10, 12, 15, 18, 24mm) to meet local requirements and exceed customer expectations. All our energy efficient windows and doors are meticulously manufactured in Sydney.