
R-Value and U-Factor for Doors and Windows
Saturday, September 19th, 2026
2019-06-27T16:53:22.000Z Read the direction correctly Higher R-value means more resistance to heat flow. Lower U-factor means less heat transfer through the rated component or assembly. For doors and windows, compare documented whole-product ratings for equivalent configurations. R-5 is not a maximum, and U-0.1 is not a universal minimum. Compare t…














