Entry from US English dictionary
The capacity of an insulating material to resist heat flow. The higher the R-value, the greater the insulating power.
- So, where R-values rate how much heat loss the material resists from passing through it, U-values rate how much heat the component allows to pass through it.
- Manufacturers usually represent the energy efficiency of windows in terms of their U-values (conductance of heat) or their R-values (resistance to heat flow).
- Don't forget that R-values are determined by material type, thickness, and installed weight per square foot, not by thickness alone.
For editors and proofreaders
What do you find interesting about this word or phrase?
Comments that don't adhere to our Community Guidelines may be moderated or removed.