[Bldg-sim] Impact of Overhangs

[Maria Kordjamshidi]

John
 
Free running: refers to the state of a building that is naturally ventilated and does not use any mechanical equipment to maintain or improve its indoor thermal condition.
 
Maria


--- On Sat, 2/6/10, John Aulbach <jra_sac at yahoo.com> wrote:


From: John Aulbach <jra_sac at yahoo.com>
Subject: Re: [Bldg-sim] Impact of Overhangs
To: "Maria Kordjamshidi" <m_kordjamshidi at yahoo.com>, "BldgSim Mailing List" <bldg-sim at onebuilding.org>, equest-users at lists.onebuilding.org, trace-users at lists.onebuilding.org, "Fareed Syed" <syedf at progressiveae.com>
Date: Saturday, February 6, 2010, 8:29 PM






Maria:
 
Excellent information.
 
Would you please describe what you mean by "free running mode"?
 
Thank you.





From: Maria Kordjamshidi <m_kordjamshidi at yahoo.com>
To: BldgSim Mailing List <bldg-sim at onebuilding.org>; equest-users at lists.onebuilding.org; trace-users at lists.onebuilding.org; Fareed Syed <syedf at progressiveae.com>
Sent: Fri, February 5, 2010 9:47:04 PM
Subject: Re: [Bldg-sim] Impact of Overhangs






Fareed
 
I have examined the effect of many parameters on the thermal performance of 6 typical houses (single storey and double storey houses) for a moderate climate of Sydney. a part of my report comes in the following for your consideration.
 
"Adding an overhang above all windows improved annual thermal performance of the typical houses in conditioned mode. However, this was not the case for the houses in free running mode. The houses presented different patterns of annual thermal performance in the different modes, responding to increments in overhang width.
Increases in overhang width of 1m resulted in an average of 4.8% enhancement in the house’s annual thermal performance in conditioned mode. The same overhang generally caused 3.7% deterioration in annual free running performance, while a slight improvement was observed in thermal performance in some cases.  The reason for these different results is made clear when comparing the seasonal performances of each house in two different house modes. 
When all the overhang widths were increased to 1m, the summer performance improved by an average of 26.6% in conditioned mode. The improvement decreased to an average of 8% for all houses in free running mode. The winter performance of the typical houses in this situation deteriorated by an average of 8.2% in conditioned mode and 11.7% in the free running mode. Thus the deterioration that was observed in the annual free running performance of some of the houses in response to the setting of overhang with a width of 1m for all windows would appear to owe more to deterioration in their winter performance and less improvement in their summer performance in free running mode than in conditioned mode." 
  
 
Hope this help
 
Maria
 


--- On Sat, 2/6/10, Fareed Syed <syedf at progressiveae.com> wrote:


From: Fareed Syed <syedf at progressiveae.com>
Subject: [Bldg-sim] Impact of Overhangs
To: "BldgSim Mailing List" <bldg-sim at onebuilding.org>, equest-users at lists.onebuilding.org, trace-users at lists.onebuilding.org
Date: Saturday, February 6, 2010, 12:22 AM








Folks,
 
Does anyone have good research data using simulations on the impact of overhangs and shadings for a typical building? 
  
I am having hard time convincing architects to reduce the glazing. They will make it a glass building if they are given a chance. 
  
I want to show them that for a 2 or 3 storied building with ton of glazing and few feet of overhang will not help the cooling/heating loads at all. 
  
I would appreciate your input. 
  
Thanks much. 
  
  
Fareed Syed EIT, LEED® AP 
Mechanical Engineer 
 
1811 4 Mile Rd NE
Grand Rapids, MI  49525 
  
Phone: 616.361.2664 ext. 3247
Direct: 616.447.3447
Fax: 616.361.1493 
syedf at progressiveae.com
www.progressiveae.com


  
 
-----Inline Attachment Follows-----


_______________________________________________
Bldg-sim mailing list
http://lists.onebuilding.org/listinfo.cgi/bldg-sim-onebuilding.org
To unsubscribe from this mailing list send  a blank message to BLDG-SIM-UNSUBSCRIBE at ONEBUILDING.ORG





      
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20100207/d988bada/attachment-0001.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/png
Size: 7502 bytes
Desc: image001.png
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20100207/d988bada/attachment-0001.png>