R-value

American

[ahr-val-yoo] / ˈɑrˌvæl ju /

noun

a measure of the resistance of an insulating or building material to heat flow, expressed as R-11, R-20, and so on; the higher the number, the greater the resistance to heat flow.

Etymology

Origin of R-value

1945–50; R, symbol for resistance

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

R-value

Make sure your pro provides a fact sheet that explains the R-value of your materials.

From Seattle Times ● Dec. 5, 2023

Most home insulation is rated between R13 and R60, with the highest R-value usually reserved for the attic.

From Seattle Times ● Dec. 5, 2023

All three systems would have the same R-value and heat loss or heat gain.

From Seattle Times ● Feb. 6, 2023

“We recommend tents sized up for one more person than expected, sleeping pads with an R-value of 3.5 or higher and a sleeping bag rated at 30 degrees or warmer.”

From Seattle Times ● Jul. 27, 2022

From an energy-saving perspective, it doesn’t matter, as long as you install the depth recommended on the package to bring the total insulation to the R-value needed where you live.

From Washington Post ● Nov. 23, 2021

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023