What is Visible Transmittance?

The visible transmittance (VT) is an optical property that indicates the amount of visible light transmitted..

The NFRC’s VT is a whole window rating and includes the impact of the frame which does not transmit any visible light. While VT theoretically varies between 0 and 1, most values among double- and triple-pane windows are between 0.30 and 0.70. The higher the VT, the more light is transmitted. A high VT is desirable to maximize daylight.

Select windows with a higher VT to maximize daylight and view.

Benefits of High VT Windows

Higher visible transmittance of a glass window can be an energy-efficient solution for your home. Arizona customers who purchase these types highly rated windows can save money on lighting bills. With a high VT rating more sunlight can be transmitted, creating a brighter environment for your household. Normally, the glass can be coated to suppress any unwanted heat that’s let in. This is good for significantly warmer areas. Visit our store location in Phoenix, AZ or contact us for more details on window & door glass ratings and how you can save money with home efficient glass.