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how do I determine U-factor for spandrel for LEED energy model?

asked 2016-02-03 16:09:04 -0600

edixon16 gravatar image

updated 2017-06-02 18:24:02 -0600

The energy model input table for the LEED submission requires proposed construction assembly U-factor to be calculated in accordance with Appendix A, however spandrel is not mentioned in Appendix A. Do I just submit a U-factor based on the Aggregate R-value of the assembly with glass, air gap, and board insulation?

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answered 2016-04-19 16:07:52 -0600

Chris Jones gravatar image

I use FramePlus Online to calculate both the glazing and spandrel performance. Go to FramePlus Online. Start FramePlus, this brings you to the glazing page, then select Switch to Spandrel Panel. When specifying the width of curtain wall, measure two panels wide as FramePlus includes one middle framing member. FramePlus doesn't have all the glazings you might want to model. Pick glass layers that are close.

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It appears that the website has changed.

edixon16 gravatar image edixon16  ( 2017-05-16 11:12:41 -0600 )edit

answered 2016-03-05 13:37:56 -0600

301_Hours gravatar image

Spandrel is opaque even though there is glass in the construction. The baseline for the spandrel area should be the same as any opaque wall assembly as required by your climate zone.

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I am referring specifically to calculating the U-value of the spandrel for the proposed design.

edixon16 gravatar image edixon16  ( 2016-04-19 15:32:27 -0600 )edit

301_Hours, just add to your answer that yes, he should do an Rvalue calculation by adding the Rvalues of the glass, air gap, insulation etc

Julien Marrec gravatar image Julien Marrec  ( 2016-04-20 16:42:13 -0600 )edit

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Asked: 2016-02-03 16:09:04 -0600

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Last updated: Apr 19 '16