R-value

American  

[ahr-val-yoo] / ˈɑrˌvæl yu /

noun

1. 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.

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Etymology

Origin of R-value

1945–50; R, symbol for resistance

Example Sentences

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

From Seattle Times

A higher R-value means the insulation is better at slowing down heat.

From Seattle Times

The ideal R-value for your home depends on what kind of space you’re insulation and the climate you live in.

From Seattle Times

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

From Seattle Times

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

From Seattle Times