Mar 23, 2015

Guide To Common Window Efficiency Terms

Imagine yourself walking into a store that only sells black sweaters but the price ranges anywhere from $10 to $200.  They seemingly look the same, but the clerk insists there are major differences between them.  How do you even begin comparing seemingly identical items?  Do you take the easy way out and just find the cheapest one or is further investigation warranted?

While it’s unlikely that you’ll run into this exact scenario, it’s not uncommon to be overwhelmed with the window to choose for your home since many look identical, but can have major differences in energy-efficiency, quality and price.  Deciphering the distinguishing characteristics between windows means understanding several technical terms.  Here’s a guide to the most common energy-efficiency terms you’re likely to see when choosing new windows to have installed in your home.

The U-Factor:

The U-factor of tells how much heat a window passes from inside your home to the outside.  U-factor ratings typically fall between 0.15 and 1.20.  The lower the U-factor, the better the window is insulated and the lower your energy bills are.
Home with large picture windows in winter

Solar Heat Gain Coefficient:

This rating focuses on the amount of heat that is brought into your house from the outdoors through the outside.  The rating system ranges from 0 to 1.  Lower numbers are better because they show that your home will stay cooler in the summer months because the window is effective in blocking heat from the sun’s rays.

Air Leakage:

This discloses the amount of outdoor air that infiltrates a home through the product.  The most common range is 0.1 and 0.3.  A lower number indicates that the product does a better job at blocking outside air.  This number is not something that manufacturers must disclose.


window overlooking a kitchen sink

Condensation Resistance:

As the name suggests, the purpose of this rating is to reveal the window’s ability to stop condensation from forming.  In this case, a higher number is better and the range can be anything from 1 to 100.  Manufacturers are not required to disclose this number.

If you are needing to update your home to more energy-efficient windows, get in touch with the window professionals at Lindus Construction today.

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