R-value

noun
\ˈär-ˌval-(ˌ)yü \

Definition of R-value 

: a measure of resistance to the flow of heat through a given thickness of a material (such as insulation) with higher numbers indicating better insulating properties — compare u-value

First Known Use of R-value

1948, in the meaning defined above

History and Etymology for R-value

probably from thermal resistance

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Dictionary Entries near R-value

Ružička

RV

RVA

R-value

RVer

RVSVP

RW

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Time Traveler for R-value

The first known use of R-value was in 1948

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