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noun U–val·ue \ˈyü-ˌval-(ˌ)yü\

Definition of U–value

  1. :  a measure of the heat transmission through a building part (as a wall or window) or a given thickness of a material (as insulation) with lower numbers indicating better insulating properties — compare r-value

Origin and Etymology of u–value


First Known Use: 1949

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