Windows

Vinyl 220 Series

Impact 4000 Data Sheet with options – http://www.krestmark.com/wp-content/uploads/2014/08/Impact-SS2.pdf

Krestmark energy performance data:

http://www.krestmark.com/wp-content/uploads/2014/06/U-Factor-and-SHGC-data_Layout-1-1.pdf


Table below is from http://www.efficientwindows.org/energystar.php with the required properties for a product to be Energy Star Rated.

Southern Zone Required Properties (mostly cooling)
U-factor Solar Heat Gain Coefficient (SHGC) Visible Transmittance (VT) Air Leakage (AL)
Windows: U-0.40
Skylights: U-0.60

EWC Recommendation: A low U-factor is useful during cold days when heating is needed. A low U-factor is also helpful during hot days when it is important to keep the heat out, but it is less important than SHGC in warm climates.

Windows: SHGC-0.25
Skylights: SHGC-0.28

EWC Recommendation: A low SHGC is the most important window property in warm climates. For superior energy performance, use windows with a SHGC of 0.25 or less.

Windows: VT=No Requirement
Skylights: VT=No Requirement

EWC Recommendation: Select windows with a higher VT to maximize daylight and view.

Windows: AL – 0.30
Skylights: AL – 0.30

EWC Recommendation: Select windows with an AL of 0.30 or less.

U=U-factor in Btu/hr-sf-°F
SHGC=Solar Heat Gain Coefficient in fraction of incident solar angle
VT=Visible Transmittance in fraction of incident visible radiation
AL=Air Leakage in cfm/s

Print Friendly, PDF & Email