R-value
noun
: 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
Examples of R-value in a Sentence
Recent Examples on the Web
This one is insulated, boosting warmth while lowering weight, resulting in a solid 3-season R-value of 4.8.
—
Will Porter, Outside, 22 Aug. 2025
Most experts agree the R-value of attic insulation should be at least R-30 (R-38 is preferable in northern climates).
—Chad Murphy, The Enquirer, 2 July 2025
This backpacking-ready pad is made with reflective insulation, earning a three-season R-value of 3.2.
—Drew Zieff, Outside Online, 22 May 2025
Winter campers will want an R-value of 7 and above for sleeping on top of snow and in below-freezing temperatures.
—Maggie Slepian, Travel + Leisure, 11 Feb. 2025
The walls have a thermal resistance or R-value of 80, so the homeowner benefits from energy savings on top of cost savings.
—Jennifer Castenson, Forbes, 15 Dec. 2024
Products like these provide, in most cases, par and above par R-values for the contractor, and that truly depends on the application on the project.
—Don Magruder, The Tennessean, 22 Sep. 2024
An R-value of 5 or above is great for winter camping.
—Emily Pennington, Condé Nast Traveler, 13 Nov. 2023
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Will Porter, Outside, 22 Aug. 2025
Most experts agree the R-value of attic insulation should be at least R-30 (R-38 is preferable in northern climates).
—Chad Murphy, The Enquirer, 2 July 2025
This backpacking-ready pad is made with reflective insulation, earning a three-season R-value of 3.2.
—Drew Zieff, Outside Online, 22 May 2025
Winter campers will want an R-value of 7 and above for sleeping on top of snow and in below-freezing temperatures.
—Maggie Slepian, Travel + Leisure, 11 Feb. 2025
The walls have a thermal resistance or R-value of 80, so the homeowner benefits from energy savings on top of cost savings.
—Jennifer Castenson, Forbes, 15 Dec. 2024
Products like these provide, in most cases, par and above par R-values for the contractor, and that truly depends on the application on the project.
—Don Magruder, The Tennessean, 22 Sep. 2024
An R-value of 5 or above is great for winter camping.
—Emily Pennington, Condé Nast Traveler, 13 Nov. 2023
Cite this Entry
“R-value.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/R-value. Accessed 6 Sep. 2025.
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