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

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See Examples For:

R-value

Your insulation’s effectiveness is measured in thermal resistance, otherwise known as R-value.

From Seattle Times ● Dec. 5, 2023

The price for closed-cell foam that’s the exact same R-value as the fiberglass is $12,410.

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

An insulation’s R-value is always printed on the label.

From Seattle Times ● Dec. 21, 2021

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