<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta content="text/html; charset=ISO-8859-1"
http-equiv="Content-Type">
<title></title>
</head>
<body text="#000000" bgcolor="#ffffff">
<br>
<br>
-------- Original Message --------
<table class="moz-email-headers-table" border="0" cellpadding="0"
cellspacing="0">
<tbody>
<tr>
<th valign="BASELINE" align="RIGHT" nowrap="nowrap">Subject: </th>
<td>Re: [Bldg-sim] usgbc response to outdoor air question</td>
</tr>
<tr>
<th valign="BASELINE" align="RIGHT" nowrap="nowrap">Date: </th>
<td>Mon, 17 Oct 2011 11:08:03 -0700</td>
</tr>
<tr>
<th valign="BASELINE" align="RIGHT" nowrap="nowrap">From: </th>
<td>Carol Gardner <a class="moz-txt-link-rfc2396E" href="mailto:gems@spiritone.com"><gems@spiritone.com></a></td>
</tr>
<tr>
<th valign="BASELINE" align="RIGHT" nowrap="nowrap">To: </th>
<td>Patrick J. O'Leary, Jr. <a class="moz-txt-link-rfc2396E" href="mailto:poleary1969@gmail.com"><poleary1969@gmail.com></a></td>
</tr>
<tr>
<th valign="BASELINE" align="RIGHT" nowrap="nowrap">CC: </th>
<td><a class="moz-txt-link-abbreviated" href="mailto:bldg-sim@lists.onebuilding.org">bldg-sim@lists.onebuilding.org</a></td>
</tr>
</tbody>
</table>
<br>
<br>
<meta content="text/html; charset=ISO-8859-1"
http-equiv="Content-Type">
<title></title>
Chances are they don't have a "straight answer" to give you. I would
recommend modeling it the way that feels right to you, using your
knowledge of how the building works and your expertise as a modeler,
and providing documentation for the choices you made and why you
believe they are correct. If your arguments hold together you might
not have any trouble at all.<br>
<br>
Carol<br>
<br>
On 10/17/2011 10:37 AM, Patrick J. O'Leary, Jr. wrote:
<blockquote cite="mid:4E9C67D8.2030300@gmail.com" type="cite">
<meta content="text/html; charset=ISO-8859-1"
http-equiv="Content-Type">
you're welcome james. now if i could only get a straight answer
on how to address baseline system sizing/outdoor air rates when
the proposed building is evaporatively cooled with 100% outdoor
air .... sizing a baseline building system of packaged dx just
doesn't sit right when the proposed is providing 20,000 cfm with
100% outdoor air. and i get mixed comments from reviewers about
too much energy savings ... or providing too much outdoor air in
the baseline ...<br>
<br>
On 10/17/11 9:31 AM, Jim Dirkes wrote:
<blockquote
cite="mid:004b01cc8cea$44423f90$ccc6beb0$@buildingperformanceteam.com"
type="cite">
<meta http-equiv="Content-Type" content="text/html;
charset=ISO-8859-1">
<meta name="Generator" content="Microsoft Word 14 (filtered
medium)">
<style><!--
/* Font Definitions */
@font-face
{font-family:Wingdings;
panose-1:5 0 0 0 0 0 0 0 0 0;}
@font-face
{font-family:Wingdings;
panose-1:5 0 0 0 0 0 0 0 0 0;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:Tahoma;
panose-1:2 11 6 4 3 5 4 4 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman","serif";
color:black;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
p
{mso-style-priority:99;
mso-margin-top-alt:auto;
margin-right:0in;
mso-margin-bottom-alt:auto;
margin-left:0in;
font-size:12.0pt;
font-family:"Times New Roman","serif";
color:black;}
span.EmailStyle18
{mso-style-type:personal-reply;
font-family:"Calibri","sans-serif";
color:#1F497D;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
<div class="WordSection1">
<p class="MsoNormal"><span style="font-size: 11pt;
font-family: "Calibri","sans-serif";
color: rgb(31, 73, 125);">Dear Patrick,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size: 11pt;
font-family: "Calibri","sans-serif";
color: rgb(31, 73, 125);"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size: 11pt;
font-family: "Calibri","sans-serif";
color: rgb(31, 73, 125);">Thank you for sharing this GBCI
response! It is very informative and, while I won’t admit
that I’ve been modeling anything incorrectly, I <u>am</u>
going to change a couple of things </span><span
style="font-size: 11pt; font-family: Wingdings; color:
rgb(31, 73, 125);">J</span><span style="font-size: 11pt;
font-family: "Calibri","sans-serif";
color: rgb(31, 73, 125);">.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size: 11pt;
font-family: "Calibri","sans-serif";
color: rgb(31, 73, 125);">In particular, I have heard on
several occasions that the Increased Ventilation credit
was a clear case of “IEQ vs. energy”; you make a decision
to trade one against the other. After reading the GBCI
response below and then double-checking with ASHRAE 90.1,
I find that they are consistent with each other and
effectively allow no penalty for the increased energy
caused by increased ventilation. Very curious,
considering there is no science which demonstrates a
health benefit for outdoor airflows greater than that
required by ASHRAE 62.1!<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size: 11pt;
font-family: "Calibri","sans-serif";
color: rgb(31, 73, 125);">The other item is that I failed
to notice (and still can’t find) anything in 621.1 which
says that unoccupied ventilation should be zero. I guess
that is OK, but is also curious, since a portion of the
ventilation calcs in 62.1 include consideration for
off-gassing materials (which are always present.)<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size: 11pt;
font-family: "Calibri","sans-serif";
color: rgb(31, 73, 125);">All in all, I’m smarter than I
was as a result of your post, so it’s a good day! Thanks
again.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size: 11pt;
font-family: "Calibri","sans-serif";
color: rgb(31, 73, 125);"><o:p> </o:p></span></p>
<div>
<p class="MsoNormal" style="text-align: center;"
align="center"><b><span style="font-size: 13.5pt;
font-family:
"Calibri","sans-serif"; color:
rgb(31, 73, 125);">The Building Performance Team<br>
</span></b><b><span style="font-size: 11pt; font-family:
"Calibri","sans-serif"; color:
rgb(31, 73, 125);">James V. Dirkes II, P.E., BEMP ,
LEED AP<br>
</span></b><span style="font-size: 11pt; font-family:
"Calibri","sans-serif"; color:
rgb(31, 73, 125);">1631 Acacia Drive NW<br>
Grand Rapids, MI 49504<br>
616 450 8653<o:p></o:p></span></p>
</div>
<p class="MsoNormal"><span style="font-size: 11pt;
font-family: "Calibri","sans-serif";
color: rgb(31, 73, 125);"><o:p> </o:p></span></p>
<div>
<div style="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;
font-family:
"Tahoma","sans-serif"; color:
windowtext;">From:</span></b><span style="font-size:
10pt; font-family:
"Tahoma","sans-serif"; color:
windowtext;"> <a moz-do-not-send="true"
class="moz-txt-link-abbreviated"
href="mailto:bldg-sim-bounces@lists.onebuilding.org">bldg-sim-bounces@lists.onebuilding.org</a>
[<a moz-do-not-send="true"
class="moz-txt-link-freetext"
href="mailto:bldg-sim-bounces@lists.onebuilding.org">mailto:bldg-sim-bounces@lists.onebuilding.org</a>]
<b>On Behalf Of </b>Patrick J. O'Leary, Jr.<br>
<b>Sent:</b> Monday, October 17, 2011 11:46 AM<br>
<b>To:</b> <a moz-do-not-send="true"
class="moz-txt-link-abbreviated"
href="mailto:equest-users@lists.onebuilding.org">equest-users@lists.onebuilding.org</a>;
<a moz-do-not-send="true"
class="moz-txt-link-abbreviated"
href="mailto:bldg-sim@lists.onebuilding.org">bldg-sim@lists.onebuilding.org</a><br>
<b>Subject:</b> [Bldg-sim] usgbc response to outdoor
air question<o:p></o:p></span></p>
</div>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">back in september there was a thread
about what the outdoor air rate in a baseline simulation
should be compared to a proposed simulation, specifically
when one is adding 30% more outdoor air to meet the ieqc2
requirement and earn 1 leed point. there were differences
of opinions about the flow rates between baseline and
proposed being either the same (as required in 90.1 app g)
or the baseline being the calculated per 62.1 and the
proposed being as designed.<br>
<br>
so i submitted a support request to the usgbc and the reply
i received is below, but in short the response is that
unless you're using dcv optionally the outdoor air rates in
the baseline and proposed energy simulations for eac1 should
be the same. the response below gives the standard
responses to differing outdoor air rate scenarios.<br>
<br>
regards,<br>
patrick<o:p></o:p></p>
<p>[Fwd: Case 00531150: General LEED Questions<o:p></o:p></p>
<p>-------- Original Message --------<o:p></o:p></p>
<table class="MsoNormalTable" border="0" cellpadding="0"
cellspacing="0">
<tbody>
<tr>
<td style="padding: 0in;" valign="top" nowrap="nowrap">
<p class="MsoNormal" style="text-align: right;"
align="right"><b>Subject: <o:p></o:p></b></p>
</td>
<td style="padding: 0in;">
<p>Case 00531150: General LEED Questions [
ref:00D49UeD.5004GN692:ref ]<o:p></o:p></p>
</td>
</tr>
<tr>
<td style="padding: 0in;" valign="top" nowrap="nowrap">
<p class="MsoNormal" style="text-align: right;"
align="right"><b>Date: <o:p></o:p></b></p>
</td>
<td style="padding: 0in;">
<p>Mon, 17 Oct 2011 06:54:51 +0000 (GMT)<o:p></o:p></p>
</td>
</tr>
<tr>
<td style="padding: 0in;" valign="top" nowrap="nowrap">
<p class="MsoNormal" style="text-align: right;"
align="right"><b>From: <o:p></o:p></b></p>
</td>
<td style="padding: 0in;">
<p>"No reply GBCI" <a moz-do-not-send="true"
href="mailto:no-reply@gbci.org"><no-reply@gbci.org></a>
<a moz-do-not-send="true"
href="mailto:no-reply@gbci.org"><no-reply@gbci.org></a><o:p></o:p></p>
</td>
</tr>
<tr>
<td style="padding: 0in;" valign="top" nowrap="nowrap">
<p class="MsoNormal" style="text-align: right;"
align="right"><b>To: <o:p></o:p></b></p>
</td>
<td style="padding: 0in;">
<p>patrick@<o:p></o:p></p>
</td>
</tr>
</tbody>
</table>
<p><o:p> </o:p></p>
<p class="MsoNormal">Dear Patrick,<br>
<br>
Thank you for contacting the Green Building Certification
Institute. <br>
<br>
You ask very good questions related to the relationship
between ASHRAE Standards 62.1 and 90.1, and how these
standards are applied across multiple LEED Rating System
prerequisites and credits.<br>
<br>
The simple answer to your question is that, for systems
without demand controlled ventilation, the outdoor air
included in EA Credit 1 energy simulations must be the same
in the Baseline and Proposed cases. If the project is
attempting IEQ Credit 2 Increased Ventilation, then the
values calculated in IEQc2 must be used in the EAc1 Basline
and Proposed case energy models. Note that IEQc2 does not
limit the project to providing only 30% more outdoor air
than AHRAE 62.1 Ventilation Rate Procedure minimums, so
higher amounts are acceptable, as long as they are modeled
identically in both the Baseline and Proposed case energy
models.<br>
<br>
The following generic LEED Review Comment applies to
ventilation systems that do not have demand controlled
ventilation:<br>
<br>
It is unclear whether the minimum outside air rates (in CFM)
were modeled identically in the Baseline and Proposed case
for all zones not having Demand Control Ventilation in the
Proposed case. Please confirm that minimum outside airflow
(in units of cfm) was modeled identically in the Baseline
and Proposed cases using the proposed case rates.
Additionally, please verify that all systems in both the
baseline and proposed case are modeled with zero outside air
flow when fans are cycled on to meet unoccupied setback
temperatures unless health or safety regulations mandate an
alternate minimum flow during unoccupied periods (in which
case, the unoccupied outside air rates should be modeled
identically in the Baseline and Proposed case).<br>
<br>
The situation becomes a bit more complicated in you have
systems that have demand controlled ventilation (often
implemented as Carbon Dioxide control of outdoor air or as
programmed control of outdoor air based on occupancy
sensors.) In this case the Baseline case energy model must
include the minimum outdoor air as determined by the ASHRAE
62.1 Ventilation Rate Procedure calculations for all systems
having demand controlled ventilation. <br>
<br>
The following generic LEED Review Comment applies to
ventilation systems that do have demand controlled
ventilation:<br>
<br>
Demand control ventilation was modeled for credit in the
proposed case. Appendix G allows schedule changes for demand
control ventilation as approved by the rating authority
(Table G3.1#4(Baseline)). As the LEED Certification rating
authority, GBCI requires that the outside air ventilation
rates for the Baseline case be modeled using minimum ASHRAE
62.1-2004 (or 2007 for LEED-NC 2009 projects) rates wherever
credit is taken for demand control ventilation in the
Proposed case. The proposed case minimum rates at design
conditions should be modeled as designed. Please verify that
the Baseline Case model reflects ASHRAE 62.1-2004 (or 2007)
minimum rates for any spaces where credit is taken for
demand control ventilation, or revise the model accordingly.
For all other spaces, please confirm that minimum outside
airflow (in units of cfm) was modeled identically in the
Baseline and Proposed cases. Additionally, please verify
that all systems in both the baseline and proposed cases are
modeled with zero outside air flow when fans are cycled on
to meet unoccupied setback temperatures unless health or
safety regulations mandate an alternate minimum flow during
unoccupied periods (in which case, the unoccupied outside
air rates should be modeled identically in the Baseline and
Proposed case).<br>
<br>
Finally, even though you don't address energy recovery in
your question, whether or not you have energy recovery in
your ventilation systems may affect how much better (or
worse) your Proposed case energy models perform in relation
to your Baseline case energy models. <br>
<br>
The following generic LEED Review Comment addresses energy
recovery in EAc1 energy models as it relates to ventilation
systems.<br>
<br>
Energy recovery is modeled for credit in the Proposed case.
Please provide further information regarding the energy
recovery efficiency, verify that outside air is modeled with
zero flow in both the Baseline and Proposed cases during
unoccupied periods when fans are cycled on to meet
unoccupied setback temperatures unless health or safety
regulations mandate an alternate minimum flow during
unoccupied periods (in which case, the unoccupied outside
air rates should be modeled identically in the Baseline and
Proposed Case), and indicate the bypass mechanism used to
bypass the energy recovery during mild conditions. <br>
<br>
I hope that helps, but if you have any further questions or
concerns, please feel free to use the contact form at <a
moz-do-not-send="true"
href="http://www.gbci.org/contactus">http://www.gbci.org/contactus</a>
and select "Follow up to GBCI Response," inputting your case
number from this email's subject line.<br>
<br>
Best Regards,<br>
<br>
Dan Katzenberger, P.E., CEM, BEMP, LEED-AP BD+C<br>
<br>
Green Building Certification Institute <br>
2101 L Street NW, Suite 500 <br>
Washington, DC 20037 <br>
800-795-1746 (phone)<br>
202 828-5110 (fax) <br>
<a moz-do-not-send="true"
href="http://www.gbci.org/contactus">www.gbci.org/contactus</a><br>
<br>
The text above represents a staff opinion of a particular
issue, and does NOT set any precedent to be upheld during a
LEED Certification Review. For official rulings in advance
of a LEED Certification Review, customers should utilize the
Formal Inquiries process available in LEED Online that
results in a Project Credit Interpretation Ruling (Project
CIR) and possibly a LEED Interpretation (formerly CIRs or
Public Rulings). Applications for LEED Certification will be
thoroughly reviewed based on USGBC Member balloted and
approved LEED Rating Systems, with addenda, and USGBC
approved LEED Interpretations, or Project CIRs administered
by GBCI, as applicable. Please note that certain inquiries
submitted to USGBC are forwarded to GBCI for reply as
appropriate.<br>
<br>
<br>
_______________________________<br>
CUSTOMER EMAIL ADDRESS: <br>
patirck@<br>
<br>
CUSTOMER INQUIRY:<br>
I am trying to verify what the minimum outdoor airflow rate
required for EAc1 is and am not sure if this requires a CIR.
<br>
<br>
If the Proposed outdoor air ventilation is a minimum of 30%
higher than the minimum required by ASHRAE 62 in order to
achieve 1 LEED point for credit IEQC2 is the Baseline
outdoor air rate also 30% higher than the minimum required
by ASHRAE 62? or would the Baseline outdoor air ventilation
rate be the minimum outdoor air rate per ASHRAE 62
calculations. <br>
<br>
In other words, if ASHRAE 62 requires a minimum of 1,000 CFM
of outdoor air, and 1,300 CFM is provided to attain 1 LEED
point via IEQC1, is the Baseline outdoor air flow rate 1,000
CFM or 1,300 CFM in the energy simulation? <br>
<br>
90.1-2007/2004 both say the minimu m outdoor airflow
rates shall be the same for both the proposed and baseline
building designs, as does the user manual. <br>
<br>
But this logic seems to reward the Proposed simulation by
conditioning the additional outdoor air supplied (300 cfm in
the example above) to achieve IEQC1 in the Baseline system
as well as the proposed. <br>
<br>
The logic of using the minimum required in the Baseline case
is reflected in EAC1 in the equipment efficiency
requirements. Baseline efficiencies are the minimum
required, e.g. SEER 13 for packaged units. <br>
<br>
It is the intent of the requirement that I am not sure is
clear. Increasing the outdoor air ventilation rate increases
the energy used to condition the outdoor air, so if the
intent is to put the onus on Proposed design to show energy
reduction/LEED compliance over the 90.1/62 requirements
shouldn't the Baseline outdoor air be the minimum air flow
rate per the ASHRAE 62 calculations? This puts the onus on
the design team to provide a design that compensates for the
increase in energy to meet IEQC2 by providing some method of
processing the increase in outdoor air while still reducing
energy consumption.<o:p></o:p></p>
</div>
<br>
<fieldset class="mimeAttachmentHeader"></fieldset>
<br>
<pre wrap="">_______________________________________________
Bldg-sim mailing list
<a moz-do-not-send="true" class="moz-txt-link-freetext" href="http://lists.onebuilding.org/listinfo.cgi/bldg-sim-onebuilding.org">http://lists.onebuilding.org/listinfo.cgi/bldg-sim-onebuilding.org</a>
To unsubscribe from this mailing list send a blank message to <a moz-do-not-send="true" class="moz-txt-link-abbreviated" href="mailto:BLDG-SIM-UNSUBSCRIBE@ONEBUILDING.ORG">BLDG-SIM-UNSUBSCRIBE@ONEBUILDING.ORG</a>
</pre>
</blockquote>
<br>
<pre wrap=""><fieldset class="mimeAttachmentHeader"></fieldset>
_______________________________________________
Bldg-sim mailing list
<a moz-do-not-send="true" class="moz-txt-link-freetext" href="http://lists.onebuilding.org/listinfo.cgi/bldg-sim-onebuilding.org">http://lists.onebuilding.org/listinfo.cgi/bldg-sim-onebuilding.org</a>
To unsubscribe from this mailing list send a blank message to <a moz-do-not-send="true" class="moz-txt-link-abbreviated" href="mailto:BLDG-SIM-UNSUBSCRIBE@ONEBUILDING.ORG">BLDG-SIM-UNSUBSCRIBE@ONEBUILDING.ORG</a>
</pre>
</blockquote>
<br>
</body>
</html>