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Views: 33     Author: Site Editor     Publish Time: 2020-02-20      Origin: Site


An Insulated Glass Unit (IGU), also referred to as Double Pane glass, consists of two or more pieces of flat glass, also known as “glass-lites”, separated by a sealed air-space. Glass options include clear, Low-E, standard or high performance tints, reflective, laminated, and decorative glass. The glass-lites of IGU can be annealed, heat-strengthened, tempered, or laminated.

IGU’s are used in residential as well as in commercial buildings. Some of the common commercial applications include vertical glazing, sloped glazing, overhead glazing, skylights, and both vision and spandrel (non-vision) areas.

Depending on the type of glass used, an IGU can be designed for:

  • Light and solar control

  • Sound control

  • UV light screening (to reduce fading)

  • Hurricane, earthquake and blast resistance

  • Security

  • Bullet resistance

  • Decorative applications

  • Security glass doors and windows

  • Display cases, glass shelves, glass partitions

  • Emergency Board-up Services

A failed IGU, often referred to as “fogged” glass, is a glass characterized as having a milky look or white scale formations between the inner and outer pieces of glass that cannot be cleaned away. Additionally, the appearance of moisture or water droplets can be seen near the edges of the internal seal. These conditions are typically a result of a failed perimeter seal and saturated desiccant. In such cases, the only remedy is to replace the IGU.

The life of an IGU varies depending on several factors, including the quality of materials used, the size of the gap between the inner and outer pane, temperature differences between the exterior and interior of the home or business, and location of the IGU in the home or business. Glass and Mirror Pros has partnered with several vendors that offer up to 10 year warranties depending on the size and application of the IGU.

Good to Know! If an IGU has been altered by the installation of a window film, the warranty will be voided by the manufacturer. To protect yourself and your investment, you should ask your window tint company if they offer a warranty for IGU that fails as a result of the applied window film or tint.


For many consumers, the primary benefit of utilizing an IGU on windows or doors in their home or business is energy-efficiency. IGU’s greatly reduce the cost of heating and cooling.

In the summer, heat is transmitted through the glass and is absorbed by the walls, furniture, and floors. By using window and door IGU’s with a low Solar Heat Gain Coefficient (SHGC), the solar radiation coming into the interior decreases. This reduces the amount of heat entering the home or business, thereby improving the interior comfort level and lessening the amount of energy needed for cooling during warm weather months. During the cooler seasons, IGU’s create warmer interior glass surfaces, reducing frost and condensation from forming.

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