I have taken credit for unoccupied ACH levels in the past, since Appendix G specific a 50% turndown from peak ACH during unoccupied hours (G3.1.1, Exception c.). My understanding is that you can take for an unoccupied turndown above and beyond a 50% reduction from peak.<div>
<br></div><div>Also, all of this only applies to systems that are 5,000 cfm or more - otherwise the baseline building exhaust fan system and operation should be the same as the proposed design.</div><div><br></div><div><br>
</div><div>Kendra Tupper, PE, LEED AP<br>Senior Consultant<br>Built Environment Team<br><br>Rocky Mountain Institute | T 303-567-8641 | F 303-245-7213 | <a href="http://www.rmi.org">www.rmi.org</a><br>
<br><br><div class="gmail_quote">On Thu, Aug 26, 2010 at 4:17 PM, Aleka Pappas <span dir="ltr"><<a href="mailto:APappas@enermodal.com">APappas@enermodal.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div text="#000000" bgcolor="#ffffff">
<font face="Calibri">When we provide energy design assistance for
labs, a significant energy efficiency strategy</font> is to try to
get the client to really consider ventilation requirements and get
them down as low as possible. This can be taken further with good
focused ventilation strategies. <br>
After going through this optimization process, though, I really
think the final modeling has to have the same ventilation airflow
rates in the baseline and proposed models (for occupied and
unoccupied periods). Different types of labs will have different
ventilation/ exhaust requirements; I don't see how 1 cfm/SF could be
be applied to all laboratory spaces.<br>
Having more resources to help design teams and clients reduce design
ventilation rates as much as possible would be really
useful....maybe there's a way to use 62.1 & Appendix G modeling
to encourage this, but it would need to be a lot more detailed than
1 cfm/ SF.<br>
<br>
<div>
<font color="#006600" face="Calibri"><b>Aleka Pappas</b></font><font face="Calibri"><br>
</font>
<div>
<div>
<div><font face="Calibri"><small><font color="#333399"><big><font color="#006600"><small>Building
Energy
Engineer</small></font></big></font></small></font>
<div>
<div>
<div>
<div>
<div>
<div>
<div>
<div>
<div>
<pre cols="72"><font color="#333399" face="Calibri"><font color="#000066"><b>ENERMODAL ENGINEERING, INC.
</b><i>Inspiring energy and resource efficient buildings.</i><b>
</b><b><a href="http://www.enermodal.com/" target="_blank">www.enermodal.com</a></b>
</font><font color="#000066">1325 E. 16th Ave.
Denver, CO 80218
<a href="mailto:APappas@enermodal.com" target="_blank">APappas@enermodal.com</a>
Office: 303.861.2070/ Direct: 720.221.1082</font></font></pre>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
<br>
On 8/26/2010 2:20 PM, Paul Erickson wrote:
<blockquote type="cite">
<div>
<p class="MsoNormal"><span style="color:rgb(31, 73, 125)">Vikram,</span></p>
<p class="MsoNormal"><span style="color:rgb(31, 73, 125)"> </span></p>
<p class="MsoNormal"><span style="color:rgb(31, 73, 125)">Good
question…a bit
interesting to try and answer. </span></p>
<p class="MsoNormal"><span style="color:rgb(31, 73, 125)"> </span></p>
<p class="MsoNormal"><span style="color:rgb(31, 73, 125)">First,
your calculations are
correct. </span></p>
<p class="MsoNormal"><span style="color:rgb(31, 73, 125)"> </span></p>
<p class="MsoNormal"><span style="color:rgb(31, 73, 125)">Second,
it is interesting that
only “educational science laboratories” are mentioned,
somehow
suggesting that their use is different from corporate and
institutional
labs. </span></p>
<p class="MsoNormal"><span style="color:rgb(31, 73, 125)"> </span></p>
<p class="MsoNormal"><span style="color:rgb(31, 73, 125)">Third,
EH&S often makes this
determination and there is no agreement among
standards/guidelines dealing with
lab ventilation so to impose this bit of Std 62 seems like
something that the
USGBC should be considering as it moves towards connecting
Appendix G to Std 62
rates. </span></p>
<p class="MsoNormal"><span style="color:rgb(31, 73, 125)"> </span></p>
<p class="MsoNormal"><span style="color:rgb(31, 73, 125)">Fourth,
related to that last
point, w</span><span style="color:rgb(31, 73, 125)">hile
Appendix G does not yet
directly require Std 62 rates for the baseline, LEED
requires Std 62 rates for
the proposed and 90.1 requires the baseline ventilation to
match the proposed.
So, it would seem that models should be reflecting the 1
cfm/sf requirement. </span></p>
<p class="MsoNormal"><span style="color:rgb(31, 73, 125)"> </span></p>
<p class="MsoNormal"><span style="color:rgb(31, 73, 125)">There
is a grey area that I
think may also be a point of discussion. Minimum exhaust
rates of various
types are often only required when the space is occupied.
As such, and
considering that many university EH&S folks are at least
beginning to bat
around the notion of, if not adopt, a 4 ACH minimum during
unoccupied periods,
it seems fair to have a value lower than 1 cfm/sf during
unoccupied
periods. What’s your perspective on this?</span></p>
<p class="MsoNormal"><span style="color:rgb(31, 73, 125)"> </span></p>
<p class="MsoNormal"><span style="color:rgb(31, 73, 125)">It’d
be good if others
chime in and help develop a consensus.</span></p>
<p class="MsoNormal"><span style="color:rgb(31, 73, 125)"> </span></p>
<p class="MsoNormal"><span style="color:rgb(31, 73, 125)">Paul</span></p>
<p class="MsoNormal"><span style="color:rgb(31, 73, 125)"> </span></p>
<p class="MsoNormal"><span style="color:rgb(31, 73, 125)"> </span></p>
<div>
<table style="width:355.5pt" border="0" cellpadding="0" width="474">
<tbody>
<tr>
<td style="width:125.25pt;padding:0.75pt" valign="top" width="167">
<p class="MsoNormal"><b><span style="font-size:10pt;color:rgb(102, 0, 0);text-transform:uppercase">Paul Erickson</span></b><b><span style="font-size:9pt;color:rgb(51, 51, 51)">
</span></b><span style="font-size:9pt;color:rgb(51, 51, 51)">LEED® AP <br>
</span><span style="font-size:10pt;color:rgb(31, 73, 125);text-transform:uppercase">SR.
Sustainable Design COnsultant</span><span style="font-size:9pt;color:rgb(51, 51, 51)"></span></p>
</td>
<td style="width:7.5pt;padding:0.75pt" valign="top" width="10">
<p class="MsoNormal"><span style="font-size:9pt;color:rgb(51, 51, 51)"> </span></p>
</td>
<td style="width:212.25pt;padding:0.75pt" valign="top" width="283">
<p class="MsoNormal"><b><span style="font-size:9pt;color:rgb(102, 0, 0)">AEI</span></b><span style="font-size:9pt;color:rgb(51, 51, 51)"> |
AFFILIATED ENGINEERS, INC. <br>
5802 Research Park Blvd. | Madison, WI 53719<br>
<br>
</span><span style="font-size:9pt;color:rgb(102, 0, 0)">P: 608.236.1112 | F: 608.238.2614</span><span style="font-size:9pt;color:rgb(51, 51, 51)"> <br>
</span><a href="mailto:perickson@aeieng.com" target="_blank"><span style="font-size:9pt;color:rgb(102, 0, 0);text-decoration:none">perickson@aeieng.com</span></a><span style="font-size:9pt;color:rgb(102, 0, 0)">
| </span><a href="http://www.aeieng.com/" target="_blank"><b><span style="font-size:9pt;color:rgb(102, 0, 0);text-decoration:none">www.aeieng.com</span></b></a><span style="font-size:9pt;color:rgb(51, 51, 51)"> </span></p>
</td>
</tr>
</tbody>
</table>
<p class="MsoNormal"><span style="color:rgb(31, 73, 125)"> </span></p>
</div>
<p class="MsoNormal"><span style="color:rgb(31, 73, 125)"> </span></p>
<div>
<div style="border-right:medium none;border-width:1pt medium medium;border-style:solid none none;border-color:rgb(181, 196, 223) -moz-use-text-color -moz-use-text-color;padding:3pt 0in 0in">
<p class="MsoNormal"><b><span style="font-size:10pt">From:</span></b><span style="font-size:10pt">
<a href="mailto:bldg-sim-bounces@lists.onebuilding.org" target="_blank">bldg-sim-bounces@lists.onebuilding.org</a>
[<a href="mailto:bldg-sim-bounces@lists.onebuilding.org" target="_blank">mailto:bldg-sim-bounces@lists.onebuilding.org</a>]
<b>On Behalf Of </b>Sami, Vikram<br>
<b>Sent:</b> Tuesday, August 24, 2010 10:49 AM<br>
<b>To:</b> <a href="mailto:bldg-sim@lists.onebuilding.org" target="_blank">bldg-sim@lists.onebuilding.org</a><br>
<b>Subject:</b> [Bldg-sim] ASHRAE 62 question</span></p>
</div>
</div>
<p class="MsoNormal"> </p>
<p class="MsoNormal">Just going through table 6.4 in ASHRAE
62.1-2007 it looks
like the minimum exhaust rates for labs (educational science
laboratories) is 1
cfm/ft2. That amounts to an ACH of 6 (for a 10ft ceiling) and
6.7 for a 9ft
ceiling. </p>
<p class="MsoNormal"> </p>
<p class="MsoNormal">Am I interpreting that correctly? Does that
mean for LEED
projects we cannot go below 6 – 7 ACH? Is there a way around
it?</p>
<p class="MsoNormal"> </p>
<p class="MsoNormal"> </p>
<p class="MsoNormal"><b><span style="font-size:9pt;color:gray">Vikram Sami</span></b><span style="font-size:9pt;color:gray">,
LEED AP</span></p>
<p class="MsoNormal"><span style="font-size:9pt;color:gray">Sustainable Design Analyst</span></p>
<p class="MsoNormal"><span style="font-size:9pt;color:gray">1382 Peachtree St. NE, Atlanta, GA
30309</span></p>
<p class="MsoNormal"><span style="font-size:9pt;color:gray">t: 404-443-7462
f: </span><span style="font-size:9pt;color:gray" lang="ES">404.892.5823 </span><span style="font-size:9pt;color:gray"> e: <a href="mailto:vikram.sami@perkinswill.com" target="_blank">vikram.sami@perkinswill.com</a>
</span><a href="http://www.perkinswill.com/" target="_blank"><span style="font-size:9pt;color:gray;text-decoration:none">www.perkinswill.com</span></a><span style="font-size:9pt;color:gray"></span></p>
<p class="MsoNormal" style="margin-bottom:3pt"><b><span style="font-size:9pt;color:gray">Perkins+Will.</span></b><span style="font-size:9pt;color:gray"> </span><span style="font-size:9pt;color:rgb(173, 212, 37)">Ideas +
buildings that honor the broader goals of society</span><span style="font-size:9pt;color:green"></span></p>
<p class="MsoNormal"><b><span style="font-size:8pt;color:gray"><img src="cid:part1.00030303.00000407@enermodal.com" alt="75logo_only.gif" border="0" height="33" width="38"></span></b><span style="font-size:9pt;color:gray">Years
of Design Innovation</span><b><span style="font-size:8pt;color:gray"></span></b></p>
<p class="MsoNormal" style="margin-top:3pt"><span style="font-size:6pt;color:gray">This
email and
any files transmitted with it are confidential and intended
solely for the
addressee. </span></p>
<p class="MsoNormal" style="margin-top:3pt"><span style="font-size:6pt;color:gray">If
you are
not the named addressee you should not disseminate,
distribute, copy, or alter
this email.</span></p>
<p class="MsoNormal"><span style="font-size:6pt;color:gray"> </span></p>
<p class="MsoNormal"><b><span style="font-size:6pt;color:gray">Please consider the environment
before printing this email.</span></b></p>
<p class="MsoNormal"> </p>
<p class="MsoNormal"> </p>
</div>
<pre><fieldset></fieldset>
_______________________________________________
Bldg-sim mailing list
<a href="http://lists.onebuilding.org/listinfo.cgi/bldg-sim-onebuilding.org" target="_blank">http://lists.onebuilding.org/listinfo.cgi/bldg-sim-onebuilding.org</a>
To unsubscribe from this mailing list send a blank message to <a href="mailto:BLDG-SIM-UNSUBSCRIBE@ONEBUILDING.ORG" target="_blank">BLDG-SIM-UNSUBSCRIBE@ONEBUILDING.ORG</a>
</pre>
</blockquote>
</div>
<br>_______________________________________________<br>
Bldg-sim mailing list<br>
<a href="http://lists.onebuilding.org/listinfo.cgi/bldg-sim-onebuilding.org" target="_blank">http://lists.onebuilding.org/listinfo.cgi/bldg-sim-onebuilding.org</a><br>
To unsubscribe from this mailing list send a blank message to <a href="mailto:BLDG-SIM-UNSUBSCRIBE@ONEBUILDING.ORG">BLDG-SIM-UNSUBSCRIBE@ONEBUILDING.ORG</a><br>
<br></blockquote></div><br></div>