What are R-Factors and U-Factors? What do they have to do with energy efficiency in glass?
Both of these factors indicate the insulating performance of the glass. You can use these factors to compare products to determine which windows and patio doors are best used in your climate. U-Factors indicate the amount of heat that escape through a window, wall, roof or other surface in an hour’s time. Lower U-Factors lose less energy than higher ones. R-Factors are just the opposite of U-Factors. They indicate the resistance to energy loss. If a piece of glass has a high R-Factors, it loses less energy.
