How to Assess a Window’s Energy Performance

Replacement windows are designed to be energy-efficient, yes, but not all of them can perform equally. The fact is that some windows are just more efficient than others because of several important factors. Renewal by Andersen® of Sacramento, the premier source of quality double-hung windows in the area, shares how the energy performance of replacement windows are assessed.

Window’s Energy

But First, a Quick Look at the NFRC

To help you determine the energy performance of a window, you’ll need to check the black-and-white NFRC (National Fenestration Rating Council) label tucked onto them. The NFRC is an independent nonprofit organization that establishes objective energy-efficiency ratings for windows, doors and skylights. It has developed a window energy rating system based on whole product performance. By taking a look at the details included in the NFRC label, you can get a clearer idea about a window’s efficiency.

Here are the metrics used by the NFRC to assess the energy performance of windows:

  • U-Factor. This measures the amount of heat that escapes your home via the windows. The lower the window’s U-factor, the less heat is lost through the unit. Replacement windows with a low U-factor are especially useful in colder areas because they can help reduce heating costs.

  • Solar Heat Gain Coefficient (SHGC). This metric determines the amount of solar heat a window is letting into your home. Windows with a lower SHGC rating absorb and transmit less solar heat into your living space–something that homeowners living in areas with a warm climate will surely appreciate. These windows can help keep the home cooler for longer periods without relying too much on air conditioning usage.

  • Visible Transmittance. This measures the amount of sunlight that can enter your home via the window. A higher number means more natural light is being streamed into your living space. Buying windows with high visible transmittance can keep your home illuminated naturally in the daytime, helping lower lighting bills.

  • Air Leakage. This optional rating measures the volume of air that leaks into your home from the outside. You’ll want a window with a low number to eliminate the potential for drafts.

  • Condensation Resistance. Another optional rating, this determines how well a window prevents moisture from forming inside it. A higher rating means less condensation can develop on or around the window.

One-Stop Shop for Well-Performing Windows

When you choose sliding or picture windows from Renewal by Andersen® of Sacramento, you’re always sure that they can provide you with reliable and energy-saving performance. Look no further for high-quality windows you’ll be happy to recommend to a friend. We proudly serve the areas in and around Rancho Cordova and Sacramento, CA. Call us today at (916) 779-5800 or fill out this contact form to schedule your window consultation.