Examining the Features of Thermally Efficient Windows

There’s no shortage of products claiming to be energy-efficient, especially in the construction segment of the market. It’s up to the discerning consumers like yourself to assess whether these claims are credible. Today’s article from your replacement windows contractor, Renewal by Andersen® of Quad Cities, discusses the features that make up a truly energy-efficient window.

Examining the Features of Thermally Efficient Windows


The U-value or U-factor is the measurement of the heat loss rate in a windows assembly. The thermal transmittance refers to the rate of transfer of heat through a structure. The lower the U-value of a window, the better it is at insulation. U-factor can be calculated by summing up the thermal resistances of all the materials. These values can be found online. If these calculations are too tedious, you may consult your windows manufacturer for the specific figures.

Solar Heat Gain Coefficient

Solar heat gain coefficient (SHGC) pertains to the amount of solar radiation that passes through your windows. Simply put, SGHC is the measurement of just how many ultraviolet (UV) rays are able to pass through your windows and into your home. UV rays are responsible for furniture fading and sunburns. The lower the SGHC, the better.

Most manufacturers display the window’s SHGC.


Look for the ENERGY STAR® label. This means that your windows have passed the energy code standards. ENERGY STAR is the product of the collaborative effort between the Department of Energy (DOE) and the Environmental Protection Agency (EPA).

National Fenestration Rating Council Label

The National Fenestration Rating Council (NFRC) label verifies whether your windows have complied with energy code standards. This particular label displays the energy features of all the components of your windows and appears on all fenestration products included in the ENERGY STAR program.

Your replacement windows company is responsible for installing your windows properly to maximize its energy-efficient properties. Turn to Renewal by Andersen of Quad Cities for all your window needs. You may contact us at (844) 366-7784. We serve Davenport, IA.