R-value

In by Mark Goodman

The thermal resistance of insulation or a glazing system. The R-value is the reciprocal of the U-value. The higher the R-value, the less heat is transmitted throughout the insulation or glazing material.

Merriam-Webster Online Dictionary
R-value (noun)
a measure of resistance to the flow of heat through a given thickness of a material (as insulation) with higher numbers indicating better insulating properties - compare u-value
R-value (Wikipedia)

R-value or rvalue may refer to:

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