U-val·​ue ˈyü-ˌval-(ˌ)yü How to pronounce U-value (audio)
: a measure of the heat transmission through a building part (such as a wall or window) or a given thickness of a material (such as insulation) with lower numbers indicating better insulating properties compare r-value

Examples of U-value in a Sentence

Recent Examples on the Web Made of several layers of materials and fabric, they are designed to provide thermal resistance (known as R-value) and prevent thermal transmittance conductivity (known as U-value). Heidi Wachter, Treehugger, 14 July 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'U-value.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History



First Known Use

1949, in the meaning defined above

Time Traveler
The first known use of U-value was in 1949

Dictionary Entries Near U-value

Cite this Entry

“U-value.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/U-value. Accessed 25 Jul. 2024.

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