Insulated GlassWhen multiple glass panes or "lites" are assembled into units, they are commonly referred to as "insulated glass", "Double glazing/ Double Glazed Units" (UK and Europe) or Insulating Glass Units (IGU). These units are produced with the intention of maximizing the thermal insulating properties of a gas contained in the space formed by the unit while at the same time providing clear vision through the unit at low temperatures.
Most IGUs are double glazed, but IGUs with three sheets or more, i.e. "triple glazing" are becoming more common due to higher energy costs. Insulated glazing may be framed in a sash, frame or in a curtain wall.Other applications of IGUs include acoustic attenuation.

IGUs are manufactured to varying degrees of performance.


The effectiveness of insulated glass can be expressed as an R-value. The higher the R-value, the greater is its resistance to heat transfer. A standard IGU consisting of regular panes of glass and air has an R-value of 0.35 K·m2/W (2 h·ft2·°F/BTU).

Using imperial units, a rule of thumb in standard IGU construction is that each change in the component of the IGU results in an increase of 1 R-value to the efficiency of the unit. Adding Argon gas increases the efficiency to about R-3. Using Low emissivity glass on surface #2 will add another R-value. Properly designed triple glazed IGUs with low emissivity coatings on surfaces #2 and #4 and filled with argon gas in the spaces result in units with R-values as high as R-5. Some multi-chambered IGUs result in R-values as high as R-12.5Insulated Glass

In some situations the insulation is in reference to noise mitigation. In these circumstances a large air space improves the noise insulation quality or Sound transmission class. Asymmetric double glazing, using different thicknesses of glass rather than the conventional symmetrical systems (equal glass thicknesses used for both lites) will improve the acoustic attenuation properties of the IGU at the cost of longevity if the unit is used to separate exterior and interior environments. This is due to the differing thermal expansion rates of the glass being used and the shear stress placed on the edge and spacer sealants. If standard air spaces are used, sulfur hexafluoride is used to replace or augment an inert gas and improve acoustical attenuation performance.

Insulated Glass



Transparency and clarity are the distinctive characteristics


The way of enhancing the safety and ability of the glass.


Decorative options to provide Style and Privacy


Provide visual obscuration while admitting light.