The below table demonstrates EnerLux’s different glass packages and their center-of-glass energy performance. Each glass package is called EL Glass XXX. The model number is derived from the first number of the glass package’s R-Factor, SHGC and VT. For example EL Glass 725 has an R-Factor between 7.0 and 7.9, a SHGC between 0.20 and 0.29 and a VT between 50% and 59%.
7 – R-Factor is 7.2
2 – SHGC is 0.21
5 – VT is 57%
|EL Glass 378||0.26||3.8||0.70||80%||Double||LoE-180 & Clear|
|EL Glass 437||0.25||4.0||0.37||70%||Double||LoE-270 & Clear|
|EL Glass 426||0.24||4.2||0.27||66%||Double||LoE-366 & Clear|
|EL Glass 413||0.24||4.2||0.18||39%||Double||LoE-340 & Clear|
|EL Glass 757||0.13||7.7||0.56||70%||Triple||LoE-180, Clear, & LoE-180|
|EEL Glass 736||0.13||7.7||0.33||62%||Triple||LoE-270, Clear, & LoE-180|
|EEL Glass 725||0.13||7.7||0.24||57%||Triple||LoE-366, Clear, & LoE-180|
|EL Glass 713||0.13||7.7||0.15||34%||Triple||LoE-340, Clear, & LoE-180|
Performance data calculated with Lawerence Berkley National Laboratory’s Window 5.2 NFRC 100-2001.
The standard EL Glass gas fill is 95% argon.
U-Factor – A measure of the rate of non-solar heat loss or gain through a material or assembly. It is expressed in units of Btu/hr-sq ft-F (W/sq m-C). The lower the U-factor, the greater a window’s resistance to heat flow and the better its insulating value.
R-Factor – A measure of the resistance of a glazing material or fenestration assembly to heat flow. It is the inverse of the U-factor (R=1/U) and is expressed in units of hr-sq ft-F/Btu. A high –R-value window has a grater resistance of heat flow and a higher insulating value than one with a low R-value.
Solar Heat Gain Coefficient (SHGC) – A measure of how well a product blocks heat caused by sunlight. The SHGC is the fraction of incident solar radiation admitted through a window (both directly transmitted and absorbed) and subsequently released inward. SHGC is expressed as a number between 0 and 1. The lower a window’s solar heat gain coefficient, the less solar heat it transmits in the house.
Visual Transmittance (VT) – A measure that shows how much light comes through a product. The visible transmittance is an optical property that indicates the amount of visible light transmitted. VT is expressed as a number between 0 and 1. The higher the VT, the more light is transmitted.