Schedule a
Free Estimate

*=required
 Contact me by:
    Email     Phone


Thermal Windows, Inc, Windows, Tulsa, OK
Tulsa World Best in the World medallion
Credit cards we accept

Financing available through



What Is An ENERGY STAR® Qualified Window?


ENERGY STAR qualified windows meet a stringent energy efficiency specification set by the Department of Energy and have been tested and certified by the NFRC (National Fenestration Rating Council). The NFRC is an independent, third-party agency that maintains a database of certified window and door energy performance information. The information includes U-factor, SHGC (Solar Heat Gain Coefficient), VT (Visible light Transmission) and other data.


ENERGY STAR qualifications are based on U-factor and SHGC ratings for each of four different climate zones (see map below). To be ENERGY STAR qualified, a window or door must meet the efficiency standard for the climate zone where it will be used.

Energy Star Zone Map

.  .  .  .  .  .  .





Did you know: There is no ENERGY STAR certification for commercial windows. ENERGY STAR applies only to residential windows and doors. Click here for details.




For more information, call us toll-free at (800) 259-7580 or visit the U.S. Department of Energy's
ENERGY STAR website: http://www.energystar.gov/