U-value
[yoo-val-yoo]
noun
a measure of the flow of heat through an insulating or building material: the lower the U-value, the better the insulating ability.
Compare R-value.
Origin of U-value
1945–50; U, symbol for internal energy
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019