If you have been visiting replacement window showrooms and hardware stores, you may have already noticed the white labels indicating window performance ratings along with the ENERGY STAR® certification label. Knowing how these labels work can help you find the right replacement windows your home needs.
How Energy Efficient Windows Work
Insulation is an important energy-efficiency component: the idea is to prevent thermal transfer, which leads to heat loss during winter and heat gain during summer. According to the U.S. Energy Information Administration, the average household consumes as much as 42% of its energy on heating and an additional 6% on air conditioning. By reducing thermal transfer through effective insulation, you can achieve significant energy savings. While the exterior walls, attic and entry doors have insulated cores, windows require a different approach to insulation. After all, glass is a naturally conductive material, which means single panel glass allow thermal transfer.
This is where Renewal by Andersen® replacement windows excel. Our replacement windows feature High-Performance™ Low-E4® glass. The dual panel design eliminates contact between interior and exterior surfaces, minimizing heat transfer. Combined with our exclusive Fibrex® material frames and precise installation methods, our windows dramatically reduce your energy consumption by as much as 25%.
NFRC Labels and Energy Ratings
Every home has unique energy efficiency requirements, so there’s no single replacement window solution that works for every home. The National Fenestration Rating Council (NFRC) came up with a standardized ratings system that gives homeowners a way to choose the right windows at point-of-purchase. Replacement windows are rated in the following aspects:
U-Factor – The U-factor rates how well a replacement window prevents heat loss. It is represented as a number between 0.20 and 1.20; the lower the value, the better insulation it has. Other products may refer to R-values instead of U-factor. It’s important to note that R-values measure the amount of heat transferred through the windows. Therefore, the lower the U-Factor, the higher its corresponding R-value.
Solar Heat Gain Coefficient (SHGC) – SHGC measures how well the window resists unwanted solar heat gain. It is represented as a number between 0.0 and 1.0, where the 0.0 means less solar heat goes through the windows.
Visible Transmittance (VT) – VT measures how much visible light goes through the windows. Represented as a number between 0.0 and 1.0, the higher value means more natural light comes through. Look for replacement windows with low SHGC and high VT values if you wish to enjoy natural lighting without the accompanying heat and ultraviolet (UV) rays.
Air Leakage (AL) – AL measures how much air goes through the windows when closed and is represented as a number between 0.1 and 0.3. Lower values mean less chances of drafts.
If you would like to know more about the energy savings you can get from Renewal by Andersen windows, call Renewal by Andersen of Omaha and Lincoln today at (402) 513-2828, or fill out our contact form to schedule a free estimate. We serve many areas in and near Omaha.