Most replacement windows come with energy performance and ENERGY STAR® certification labels. But what do these labels mean?
Energy Performance Labels
Energy performance labels are the white labels provided by the National Fenestration Rating Council® (NFRC). These labels indicate performance ratings of the product’s energy efficiency. Unlike most ratings organizations, the NFRC does not categorize “good” or “bad” products. The labels simply state a particular product’s ratings. These labels can be found on fenestrations: windows, doors and skylights.
The NFRC’s ratings are divided into four categories:
A product’s insulation is measured by its U-factor or U-value. A low rating means low heat transmission and better insulation. Some literature on replacement windows refer to window insulation as R-value, which measures resistance to heat flow. Therefore, a product with a very low U-factor rating will have a correspondingly high R-value.
Solar Heat Gain Coefficient (SHGC)
SHGC measures resistance against heat gain from infrared radiation. Low values indicate less heat gain. A bay window or other window styles with large glass areas can benefit from glass with low-E coatings like our High Performance™ Low-E4® glass, which selectively blocks solar heat.
Visible transmittance (VT) measures how well a product allows natural light into the room. A higher VT value means better indoor illumination. The aforementioned low-E coatings make it possible to have windows that allow natural light in without heating up your indoor spaces.
Air leakage measures how much air can pass through the product. A low air leakage value means less chances of experiencing drafts.
ENERGY STAR® Label
ENERGY STAR is an initiative that’s intended to give consumers an easy way to identify energy-efficient products and make informed decisions at the point of purchase. ENERGY STAR labels give homeowners the assurance that they are buying energy-efficient replacement windows without having to delve into and compare energy ratings. ENERGY STAR ratings apply to a diverse selection of products that includes computers and washing machines.
Renewal by Andersen® of Wyoming is your leading provider of window replacement services. Give us a call at (307) 472-2199. You can also fill out our contact form to schedule an appointment. We serve customers in Laramie, Casper and Cheyenne, WY.