[Bldg-sim] Minimum Ventilation Air in Proposed and Baseline - Breathing Zone or Outdoor Air Intake

[West, Scott P]

Aaron,
ASHRAE 90.1-2007 Addendum bj allows modelers to take energy savings credit for HVAC systems that increase air distribution effectiveness and use demand control ventilation.  This can therefore result in different ventilation rates between Baseline and Proposed models.  USGBC allows modelers to apply any ASHRAE Addenda they want for that version of the standard as long as it is applied uniformly and clearly stated.

Scott P. West, P.E., LEED AP BD+C, BEAP, BEMP | JACOBS | Mechanical Engineer | Energy & Power Solutions | 817.222.8512 office | 817.897.1882 cell | scott.west at jacobs.com<mailto:rick.zilar at jacobs.com> | www.jacobs.com<http://www.jacobs.com/> | www.jacobs.com/energyportfolio<http://www.jacobs.com/energyportfolio>

From: Aaron Smith [mailto:asmith at mreng.ca]
Sent: Friday, December 13, 2013 2:08 PM
To: bldg-sim at lists.onebuilding.org
Subject: [Bldg-sim] Minimum Ventilation Air in Proposed and Baseline - Breathing Zone or Outdoor Air Intake

Hi,

We've received a nice boost in some models in Canada lately as the Proposed and Baseline designs only need to have the same amount of outdoor air in the breathing zone under CaGBC Rules.  Meaning that if your baseline design is VAV Reheat and your proposed design is chilled beam and baseboard heating then your proposed design will have to condition somewhere in the range of 40% less outdoor air due to higher zone effectiveness and system efficiency. It makes a lot of sense to me and becomes a significant energy savings measure.

Is this allowed by the USGBC or by ASHRAE?  I just read in 90.1 in G.3.1.2.5 that "Minimum outdoor air ventilation rates shall be the same for the proposed and baseline designs."  That doesn't specify whether they mean in the breathing zone or outdoor air intake but I think most assume it to be the outdoor air intake.

Aaron



Aaron Smith, P.Eng
LEED(r) AP BD+C, M-ASHRAE, BEMP, Mechanical Engineer



    [cid:image001.jpg at 01CEF819.91B8EED0]

[cid:image003.jpg at 01CEF819.CD9BBE50]





     t: (902) 422-7393
     f: (902) 423-4945
     e: asmith at mreng.ca<mailto:asmith at mreng.ca>






The electronic message contained herein is private and confidential, intended only for the recipient(s) specified. If you have received this message in error, please delete it and notify us immediately.  Any accompanying files are supplied as a matter of courtesy only.  The data are without warranty of any kind.  Any person or business making use of the data is responsible for confirming its accuracy and completeness.  M&R Engineering Ltd. is not responsible for edited or produced versions of this digital information.




________________________________
NOTICE - This communication may contain confidential and privileged information that is for the sole use of the intended recipient. Any viewing, copying or distribution of, or reliance on this message by unintended recipients is strictly prohibited. If you have received this message in error, please notify us immediately by replying to the message and deleting it from your computer.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20131213/7f00b614/attachment-0001.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image001.jpg
Type: image/jpeg
Size: 1849 bytes
Desc: image001.jpg
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20131213/7f00b614/attachment-0006.jpg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image002.jpg
Type: image/jpeg
Size: 77404 bytes
Desc: image002.jpg
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20131213/7f00b614/attachment-0007.jpg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image003.jpg
Type: image/jpeg
Size: 2167 bytes
Desc: image003.jpg
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20131213/7f00b614/attachment-0008.jpg>