Do Your Windows Pass The “Miles-Per Gallon” Test?
How To Find The Most Energy Efficient Replacement Windows For Naperville & Surrounding Areas.
Almost everything you need to know about the energy efficiency of a window can be found on the NFRC label attached to it. This label appears on all windows and is the only measurement accepted by the US Department of Energy’s Energy Star program.
The NFRC label has multiple numbers that indicate different efficiency measurements. The most important number for replacement windows is the U-Factor.
Think of U-Factor like the “miles per gallon” rating on your car—it tells you how efficient the window is. Here is what you need to know about U-Factor:
- A lower number is better. The lower the U-Factor, the greater a window’s resistance to heat flow and the better its insulating properties.
- U-Factor for the Illinois market ranges between .18 (excellent) and .41 (poor)
- The average existing window (8+ years old) has an average U-Factor of .32 to .35 (poor)
- You can expect to save approximately $30 per year in energy costs for every .10 you lower the U-value of your windows
- Example: .20 windows could save you $300 per year in energy costs compared to .30 ones
- Examples and estimates assume average conditions and can vary depending on many factors
- Sunrise Restorations windows are rated .18 and are the best you can get in this market
While U-Factor is the most essential rating for replacement windows near Naperville, Elmhurst, Downers Grove, and surrounding areas, other ratings are important too. Here is what you need to know about each rating:
- Solar Heat Gain Coefficient: This rating measures the solar radiation a window admits. The rating is expressed in a number between 0 and 1, with lower numbers being better. Great replacement windows near Naperville will have a SHGC of less than 0.3; average windows between .4 and .7; poor windows between .8 and 1.0. Sunrise Windows test at .22.
- Visible Transmittance: VT indicates the amount of visible light transmitted, and includes the impact of the frame which does not transmit any visible light. The rating is represented as a number between 0 and 1, with the higher number being better. Most windows measuring between .3 and .7. A high VT is desirable to maximize daylight.
- Air Leakage: Indicated by the amount of air that passes through a square foot of window. Lower numbers are desirable. 0.1 is considered outstanding (and is also the lowest published rating on any label); 0.2 is good; 0.3 is average; 0.4 or higher is unacceptable. Restorations’ Double Hungs rate .04 and Casements rate .01 – both are industry best!
- Condensation Resistance: This measures a window’s ability to resist condensation on the interior. Higher numbers are desired, and are expressed between 1 and 100. Anything under 50 is unacceptable; 50 to 60 is good; 60 or more is very good.
See how the Restorations Window by Sunrise, is the most energy efficient, long lasting option for your home. Restorations have top ratings in the efficiency categories above, and more. Contact us today to schedule a free, no-pressure consultation. We would love to hear from you.