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<DIV>Matthew,</DIV>
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<DIV>I think what you need to do is pull the opaque portion of the curtain wall out. If the remaining glazing fraction is above 40%, than that portion needs to be reduced in you baseline model. </DIV>
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<DIV>Mike</DIV>
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<DIV>Michael Rosenberg<BR>Oregon Department of Energy<BR>625 Marion St. N.E.<BR>Salem, OR 97301-3742<BR>Phone : (503) 373-7809<BR>Fax: (503) 373-7806<BR><BR>>>> Matthew Higgins <higgins@edi-arch.com> 2/14/2008 10:29:05 AM >>><BR></DIV>
<DIV style="COLOR: #000000">Michael - I assume you saw my previous post? (Below).... What I am wondering is how LEED/ASHRAE 90.1-2004 Appendix-G treats glass curtain walls in baseline models: either as a curtain wall with 90.1 climate-specific glass properties or if I need to reduce the amount of glazing to 40% (the prescriptive maximum Window/Wall ratio).<BR><BR>Your thoughts?<BR><BR>*PREVIOUS POST*<BR><BR>Has anyone modeled, submitted, and certified a LEED building with a <BR>glass curtain wall?<BR><BR>I ask because I am wondering how to treat the curtain wall in the <BR>baseline model. I've tried two scenarios thus far and there is a 10% <BR>consumption difference between them. The only thing that differs between <BR>the two is that the lower consuming model has a 40% window-to-wall area <BR>where the other is still a glass curtain wall, but using Appendix G <BR>window properties. And to put this in perspective the curtain wall is <BR>facing NNE and is 3 stories high.<BR><BR>I would also truly appreciate any reference to a LEED CIR regarding this <BR>issue, if there is one.<BR><BR>Matthew Higgins, LEED AP<BR>Technical Specialist<BR>Environmental Dynamics, Inc.<BR>Architecture and Sustainability Consulting Services<BR>505.242.2851<BR><BR><BR><BR>Matthew Higgins wrote:<BR><BR>>Has anyone modeled, submitted, and certified a LEED building with a <BR>>glass curtain wall?<BR>><BR>>I ask because I am wondering how to treat the curtain wall in the <BR>>baseline model. I've tried two scenarios thus far and there is a 10% <BR>>consumption difference between them. The only thing that differs between <BR>>the two is that the lower consuming model has a 40% window-to-wall area <BR>>where the other is still a glass curtain wall, but using Appendix G <BR>>window properties. And to put this in perspective the curtain wall is <BR>>facing NNE and is 3 stories high.<BR>><BR>>I would also truly appreciate any reference to a LEED CIR regarding this <BR>>issue, if there is one.<BR>><BR>> <BR>><BR><BR>_______________________________________________<BR>Bldg-sim mailing list<BR><A href="http://lists.onebuilding.org/listinfo.cgi/bldg-sim-onebuilding.org">http://lists.onebuilding.org/listinfo.cgi/bldg-sim-onebuilding.org</A><BR>To unsubscribe from this mailing list send a blank message to BLDG-SIM-UNSUBSCRIBE@ONEBUILDING.ORG<BR></DIV></BODY></HTML>