Understanding Energy Efficiency Ratings

When choosing replacement windows for your home, it’s important to choose products that are energy efficient. However, there are so many options available that all claim to be energy efficient that it can be hard to sort through your options and find the best one for your home. There are a variety of ratings and labels related to energy efficiency that you can find about a window. In this article, we’ll break down what those different ratings, labels, and numbers mean so that you have a thorough understanding of them.

What Do ENERGY STAR® Ratings Mean for Windows?

A well-known rating that applies to everything from replacement windows to refrigerators and lightbulbs, ENERGY STAR® certifications are easy to recognize and understand. An ENERGY STAR label on a replacement window means that the product has met a specific set of energy-efficiency standards as determined by the U.S. Environmental Protection Agency or the U.S. Department of Energy. These standards vary depending on the type of product, but an ENERGY STAR® label on a replacement window is an easy thing to look for to know that you’re receiving energy-efficient windows for your home.

Understanding Energy Efficiency Ratings on NFRC Labels

In addition to checking for an ENERGY STAR® label, you can also look at energy ratings on the NFRC label. The National Fenestration Rating Council (NFRC) provides a label with numerous performance ratings specifically for windows. This allows for a more granular look at the performance of a specific window. And, because the label is standardized and ratings come from independent testing and certification, NFRC labels make it easier to compare different energy-efficient windows. Here are some of the key ratings you’ll find on the NFRC label for windows:
• U-Factor – The U-factor indicates how well a window prevents heat from escaping from your home. A lower number is better because it indicates that the window is more effective at keeping heat inside your home.
• Solar heat gain coefficient – This is the opposite of U-factor. It measures how well the window prevents heat gain through the window. A lower number is better, as it means less heat transferring into your home from outside.
• Visible transmittance – Visible transmittance has to do with how much natural light can enter your home. A higher number is better, as you’ll let in more light without having to rely on artificial light sources as much.
• Air leakage – This is a measure of how much air can enter your home through the window. A lower number is better, as it indicates less airflow into the house.

Choosing Energy-Efficient Windows for Your Home

Understanding these energy efficiency ratings can help you make an informed decision about the replacement windows you choose for your home. By checking for an ENERGY STAR rating and comparing different ratings from the NFRC label, you’ll be able to make an informed window purchasing decision so that you can proceed with your project with confidence.
If you’d like more assistance understanding energy efficiency ratings on windows, contact NewSouth Window Solutions today.