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Understanding the NFRC and Energy Star Labels

energy star

Updating the doors and windows of your home is not a small undertaking, especially if you want the best in quality, appearance, and insulation. In order to choose what’s best for your home and your energy bill, it’s helpful to understand exactly what you’re paying for. To help you decide, there are two rating systems to consider in window and door replacements - Energy Star and National Fenestration Rating Council (NFRC). While both stickers are good to see on your potential new windows and doors, the NFRC label will tell you more details than the Energy Star one. Let’s take a look at both labels to better understand what they mean.

Energy Star Ratings

There are two measurements that Energy Star takes into account when it comes to window and door performance: U-Factor and Solar Heat Gain Coefficient (discussed below). Who sets the guidelines for Energy Star ratings? These standards are strict and set in place by the federal government. If you see an Energy Star label on the door or window you’re looking to purchase, you can rest assured that they’ve been thoroughly tested and meet the efficiency criteria set up by the US government. However, if you want more detailed information, you should look for an NFRC label.

National Fenestration Rating Council (NFRC)

The NFRC label will typically list five measurements. While Energy Star only worries about two of them, the other three measurements will help you judge just how well a window or door will perform when used in a specific application, such as how much light it will let in once it has been installed. More measurements and rating criteria give you more information to work with to make an informed decision on your purchase. The five measurements used by NFRC are as follows:

U-Factor - This number ranges between 0.20 and 1.20. The lower the number, the better the insulation provided by the door or window. There are recommendations of range based on the climate in which you live. For example, if you live in the chilly North of the US, you’ll want that number to be around 0.35.

Solar Heat Gain Coefficient (SHGC) - This rating ranges between 0 to 1. The lower the number, the less solar radiation (heat) the door or window will allow inside. As with the U-Factor, the number you want to look for will vary based on the region you live in. By going with a higher SHGC number in the cooler climates, the sun’s warmth can help heat your home by coming through the windows.

Visible Transmittance - This measurement also ranges between 0 to 1, but instead of showing how much heat will transfer through the opening, it’s based on how much light is allowed through. It applies to regular windows and to doors that have built-in windows. A lower number means that the room will be dimmer, and a higher number means the room will be brighter. Check these numbers if you’re looking to reduce the glare or increase the natural light coming into a room.

Air Leakage - 0.3 is the standard building code measurement when it comes to this rating. The lower the number, the more airtight the installation will be. Energy Star standards don’t bother looking at air leakage, as they consider it to be too difficult to measure and too variable over time. Nevertheless, using this NFRC measurement can help you decide as you compare similar products.

Condensation Resistance - This range goes from 0 to 100 and measures the amount of condensation that a door or window allows to build up on its surface. The lower the number, the less condensation will develop. If your window is Energy Star rated, they are always considered to be good at resisting condensation, so this number might not affect your final purchase.

Understanding what the Energy Star and NFRC labels mean and why they’re important will put you in a more knowledgeable position as you go to purchase new doors and windows for your home. Click To Tweet

Understanding what the Energy Star and NFRC labels mean and why they’re important will put you in a more knowledgeable position as you go to purchase new doors and windows for your home. New installments can help lower your energy costs and add some new curb appeal to your home at the same time. Pay particular attention to the U-Factor and SHGC ratings for energy savings and the Visible Transmittance rating for lighting aesthetics. Check out those labels on your next door or window purchase, so that you know you’re making a great decision in what to use to upgrade your home!