How to read a window label

Learn how to read a window label by understanding key ratings like U‑Factor, Solar Heat Gain Coefficient, Visible Transmittance, and Air Leakage. Use these metrics to compare window performance and choose the right product for your home.

By understanding the numbers and codes on this label , you can make an economical decision when replacing the windows in your home.
How to Read Window Labels

Get a better understanding of the qualities an NFRC window label measures, so you can choose the new or replacement window that is best for your home.
CR tells you how to read energy-efficiency labels on replacement windows , explaining terms like U-factor and SHGC and how a window becomes Energy Star certified.

How to Read Window Ratings
Learn how to read window ratings like U-Factor, SHGC, & VT to choose windows . Understand NFRC labels & make the right choice for your home.
The NFRC Label is a window sticker that tells homeowners a lot about the product's efficiency ratings. Here's how to read them.

How to Read Window Labels
A window label can tell you a lot about the performance and energy efficiency of a product. Read about the primary factors that are measured on a window label and you'll be adequately prepared to compare different brands and types of windows — ultimately helping you select a window that is right for your home.
Different ratings can make for drastically different window performance since the grades help indicate how a window will perform in different types of climates and extreme weather. For that reason, understanding how window ratings work can be a great advantage when it comes to setting your home up for success.

Window Ratings
Know how to buy energy-efficient windows with window ratings. Find out about window ratings certifications, ENERGY STAR® program, and more.






Learn what the manufacturer sticker on your window really means so you can compare efficiency performance and value before upgrading your home.