The NFRC U-value accounts for radiant heat transfer across the gap between the two panes,
not the radiant exchange between the outside surface of the glazing and the outside
conditions. Therefore, there is no double-counting.

Joe

Joe Huang
White Box Technologies, Inc.
346 Rheem Blvd., Suite 108D
Moraga CA 94556
yjhuang at whiteboxtechnologies.com
http://weather.whiteboxtechnologies.com for simulation-ready weather data
(o) (925)388-0265
(c) (510)928-2683
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