[Bldg-sim] Glas Curtain Wall - Appendix G

[Matthew Higgins]

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).

Your thoughts?

*PREVIOUS POST*

Has anyone modeled, submitted, and certified a LEED building with a 
glass curtain wall?

I ask because I am wondering how to treat the curtain wall in the 
baseline model. I've tried two scenarios thus far and there is a 10% 
consumption difference between them. The only thing that differs between 
the two is that the lower consuming model has a 40% window-to-wall area 
where the other is still a glass curtain wall, but using Appendix G 
window properties. And to put this in perspective the curtain wall is 
facing NNE and is 3 stories high.

I would also truly appreciate any reference to a LEED CIR regarding this 
issue, if there is one.

Matthew Higgins, LEED AP
Technical Specialist
Environmental Dynamics, Inc.
Architecture and Sustainability Consulting Services
505.242.2851



Matthew Higgins wrote:

>Has anyone modeled, submitted, and certified a LEED building with a 
>glass curtain wall?
>
>I ask because I am wondering how to treat the curtain wall in the 
>baseline model. I've tried two scenarios thus far and there is a 10% 
>consumption difference between them. The only thing that differs between 
>the two is that the lower consuming model has a 40% window-to-wall area 
>where the other is still a glass curtain wall, but using Appendix G 
>window properties. And to put this in perspective the curtain wall is 
>facing NNE and is 3 stories high.
>
>I would also truly appreciate any reference to a LEED CIR regarding this 
>issue, if there is one.
>
>  
>