R-value

noun
\ ˈär-ˌval-(ˌ)yü How to pronounce R-value (audio) \

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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The first known use of R-value was in 1948

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Dictionary Entries near R-value

Ružička

RV

RVA

R-value

RVer

RVSVP

RW

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Statistics for R-value

Cite this Entry

“R-value.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/R-value. Accessed 24 January 2020.

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