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Do U-values of wall assemblies account for infiltration?

kevin_kircher | Posted in General Questions on

Possibly silly question, but when someone writes a guideline like “the overall U-value of a wall assembly (including insulation, framing, and windows) is about 1 to 2 W/m^2/K,” does that account for infiltration of outdoor air?

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  1. Expert Member
    Michael Maines | | #1

    No, U-factors are for steady-state conditions assuming no air leakage.

  2. kevin_kircher | | #2


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