<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:x="urn:schemas-microsoft-com:office:excel" xmlns:p="urn:schemas-microsoft-com:office:powerpoint" xmlns:a="urn:schemas-microsoft-com:office:access" xmlns:dt="uuid:C2F41010-65B3-11d1-A29F-00AA00C14882" xmlns:s="uuid:BDC6E3F0-6DA3-11d1-A2A3-00AA00C14882" xmlns:rs="urn:schemas-microsoft-com:rowset" xmlns:z="#RowsetSchema" xmlns:b="urn:schemas-microsoft-com:office:publisher" xmlns:ss="urn:schemas-microsoft-com:office:spreadsheet" xmlns:c="urn:schemas-microsoft-com:office:component:spreadsheet" xmlns:odc="urn:schemas-microsoft-com:office:odc" xmlns:oa="urn:schemas-microsoft-com:office:activation" xmlns:html="http://www.w3.org/TR/REC-html40" xmlns:q="http://schemas.xmlsoap.org/soap/envelope/" xmlns:rtc="http://microsoft.com/officenet/conferencing" xmlns:D="DAV:" xmlns:Repl="http://schemas.microsoft.com/repl/" xmlns:mt="http://schemas.microsoft.com/sharepoint/soap/meetings/" xmlns:x2="http://schemas.microsoft.com/office/excel/2003/xml" xmlns:ppda="http://www.passport.com/NameSpace.xsd" xmlns:ois="http://schemas.microsoft.com/sharepoint/soap/ois/" xmlns:dir="http://schemas.microsoft.com/sharepoint/soap/directory/" xmlns:ds="http://www.w3.org/2000/09/xmldsig#" xmlns:dsp="http://schemas.microsoft.com/sharepoint/dsp" xmlns:udc="http://schemas.microsoft.com/data/udc" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:sub="http://schemas.microsoft.com/sharepoint/soap/2002/1/alerts/" xmlns:ec="http://www.w3.org/2001/04/xmlenc#" xmlns:sp="http://schemas.microsoft.com/sharepoint/" xmlns:sps="http://schemas.microsoft.com/sharepoint/soap/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:udcs="http://schemas.microsoft.com/data/udc/soap" xmlns:udcxf="http://schemas.microsoft.com/data/udc/xmlfile" xmlns:udcp2p="http://schemas.microsoft.com/data/udc/parttopart" xmlns:wf="http://schemas.microsoft.com/sharepoint/soap/workflow/" xmlns:dsss="http://schemas.microsoft.com/office/2006/digsig-setup" xmlns:dssi="http://schemas.microsoft.com/office/2006/digsig" xmlns:mdssi="http://schemas.openxmlformats.org/package/2006/digital-signature" xmlns:mver="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns:mrels="http://schemas.openxmlformats.org/package/2006/relationships" xmlns:spwp="http://microsoft.com/sharepoint/webpartpages" xmlns:ex12t="http://schemas.microsoft.com/exchange/services/2006/types" xmlns:ex12m="http://schemas.microsoft.com/exchange/services/2006/messages" xmlns:pptsl="http://schemas.microsoft.com/sharepoint/soap/SlideLibrary/" xmlns:spsl="http://microsoft.com/webservices/SharePointPortalServer/PublishedLinksService" xmlns:Z="urn:schemas-microsoft-com:" xmlns:st="" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv=Content-Type content="text/html; charset=iso-8859-1">
<meta name=Generator content="Microsoft Word 12 (filtered medium)">
<!--[if !mso]>
<style>
v\:* {behavior:url(#default#VML);}
o\:* {behavior:url(#default#VML);}
w\:* {behavior:url(#default#VML);}
.shape {behavior:url(#default#VML);}
</style>
<![endif]-->
<style>
<!--
/* Font Definitions */
@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;}
@font-face
{font-family:Times;
panose-1:2 2 6 3 5 4 5 2 3 4;}
@font-face
{font-family:"Stylus BT";
panose-1:2 14 4 2 2 2 6 2 3 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri","sans-serif";}
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.MsoAcetate, li.MsoAcetate, div.MsoAcetate
{mso-style-priority:99;
mso-style-link:"Balloon Text Char";
margin:0in;
margin-bottom:.0001pt;
font-size:8.0pt;
font-family:"Tahoma","sans-serif";}
span.BalloonTextChar
{mso-style-name:"Balloon Text Char";
mso-style-priority:99;
mso-style-link:"Balloon Text";
font-family:"Tahoma","sans-serif";}
span.EmailStyle19
{mso-style-type:personal;
font-family:"Calibri","sans-serif";
color:windowtext;}
span.EmailStyle20
{mso-style-type:personal;
font-family:"Calibri","sans-serif";
color:#1F497D;}
span.EmailStyle21
{mso-style-type:personal-reply;
font-family:"Calibri","sans-serif";
color:#1F497D;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;}
@page Section1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.Section1
{page:Section1;}
-->
</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]-->
</head>
<body lang=EN-US link=blue vlink=purple>
<div class=Section1>
<p class=MsoNormal><span style='color:#1F497D'>Nick and Vikram, double skin
facades or climate walls or windows have been around for many years now. Vikram's
question is really how do you produce a back of the envelope calculation to see
if a double skin façade is a viable option. Well here goes, the basic improvement
by using a double façade is the improvement of the U value decreasing energy
loss. Take a look around the world and the successful applications of double
facades is mostly in regions where heating is the dominant energy consumer. One
of the first things were learnt more than 30 years ago was the U value was
improved so long as air was ventilated through the cavity, but what happened to
the U value when the air system was switched off after occupation? which consumed
more energy, the energy loss of the building without the function of the double
façade or the energy consumption of the air system to maintain the
functionality of the double façade. Beyond the improvement of the U value we
can then start looking at improved shading coefficients and surface temperature
control of the inside surface of the double façade. For these different aspects
of double façade design I believe the design criteria was simplified in a
series of tables issued in a couple of ISSO publications in the 80's. These
documents will get you rough data to be able to assess whether or not the
double façade is feasible. As far as deluxe simulation tools probably the best
is the ROOM program by Mike Holmes and Andrew White and then there is also
TRNSYS.<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>Getting back to Nick's comments,
I have found over the years that the most comments regarding double facades
come from people that have never designed them, here I am referring to the
article and not you Nick.<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>I first started designing double
facades in the late 70's in the Netherlands and over the years have designed
quite few and completed quite a few repair jobs on attempted double facades.
One thing I have learned is that if it isn't cold then the double façade is
there for show only!<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<div>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span
style='color:black'>Peter Simmonds, Ph.D. </span></b><span style='font-size:
10.0pt;font-family:"Arial","sans-serif";color:gray'><br>
</span><b><span style='font-size:10.0pt;color:gray'>Senior Associate<br>
Head of the Advanced Technology Group<br>
</span></b><b><span style='font-size:10.0pt;color:black'>IBE Consulting
Engineers</span></b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:gray'><br>
</span><b><span style='font-size:10.0pt;color:gray'>14130 Riverside Drive,
Suite 201</span></b><span style='font-size:12.0pt;font-family:"Times New Roman","serif";
color:#1F497D'><br>
</span><b><span style='font-size:10.0pt;color:gray'>Sherman Oaks, CA 91423 <br>
p: (818) 377-8220 </span></b><b><span style='font-size:10.0pt;color:gray'>x246</span></b><b><span
style='font-size:10.0pt;color:gray'> m: (818) 219-1284 f: (818) 377-8230<br>
<br>
</span></b><b><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:gray'><a href="http://www.ibece.com/" title="http://www.ibece.com/"><span
style='font-family:"Calibri","sans-serif";color:gray;text-decoration:none'>www.ibece.com</span></a><br>
</span></b><b><i><span style='font-size:10.0pt;color:gray'>Ideas for the built
environment</span></i></b><span style='font-size:12.0pt;font-family:"Times New Roman","serif";
color:#1F497D'><o:p></o:p></span></p>
</div>
</div>
<p class=MsoNormal><span style='font-size:8.0pt;font-family:"Times","serif";
color:#1F497D'>This e-mail message, including any attachments, is for the sole
use of the intended recipient(s) and may contain confidential and privileged
information. Any unauthorized review, use, disclosure, or distribution is
prohibited. If you are not the intended recipient, please contact the sender by
reply e-mail and destroy all copies of the original message.</span><span
style='color:#1F497D'><o:p></o:p></span></p>
<div>
<div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'>
<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span
style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Nick Caton
[mailto:ncaton@smithboucher.com] <br>
<b>Sent:</b> Thursday, November 11, 2010 8:11 AM<br>
<b>To:</b> Sami, Vikram; bldg-sim@lists.onebuilding.org<br>
<b>Subject:</b> Re: [Bldg-sim] Is there a quick model for double skins facades?<o:p></o:p></span></p>
</div>
</div>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span style='color:#1F497D'>Hi Vik,<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>I hate to trample over
anyone’s little flower patch, but I’ve read some scathing
assessments of double-facades as an energy-saving strategy. You might
want to check this and the associated references out: <a
href="http://www.buildingscience.com/documents/insights/bsi-007-prioritizing-green-it-s-the-energy-stupid">http://www.buildingscience.com/documents/insights/bsi-007-prioritizing-green-it-s-the-energy-stupid</a>.<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>That said you might not be
satisfied until you develop your own conclusions. Proponents of this
approach repeatedly cite benefits of CFD, so to give a
“fair/proper” assessment any tool you work with would probably need
to be modeling convective airflows between floors.<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>~Nick<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<div>
<p class=MsoNormal><span style='color:#1F497D'><img border=0 width=119
height=37 id="Picture_x0020_1" src="cid:image001.jpg@01CB817C.995DF2F0"
alt="cid:489575314@22072009-0ABB"></span><b><span style='font-family:"Stylus BT","sans-serif";
color:#2D4D5E'><o:p></o:p></span></b></p>
<p class=MsoNormal><b><span style='font-family:"Stylus BT","sans-serif";
color:#2D4D5E'><o:p> </o:p></span></b></p>
<p class=MsoNormal><b><span style='font-family:"Stylus BT","sans-serif";
color:#2D4D5E'>NICK CATON, E.I.T.</span></b><b><span style='font-size:12.0pt;
font-family:"Stylus BT","sans-serif";color:#2D4D5E'><o:p></o:p></span></b></p>
<p class=MsoNormal><span style='font-size:7.5pt;color:#CC9900'>PROJECT ENGINEER</span><span
style='font-size:7.5pt;font-family:"Times New Roman","serif";color:#CC9900'><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;color:#2D4D5E'>25501 west
valley parkway<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;color:#2D4D5E'>olathe ks 66061<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;color:#2D4D5E'>direct 913
344.0036<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;color:#2D4D5E'>fax 913
345.0617<o:p></o:p></span></p>
<p class=MsoNormal><i><span style='font-size:10.0pt;color:#2D4D5E'>Check out
our new web-site @ </span></i><span style='color:#1F497D'><a
href="www.smithboucher.com" title="blocked::www.smithboucher.com"><span
style='font-size:10.0pt'>www.smithboucher.com</span></a></span><u><span
style='font-size:10.0pt;color:blue'> </span></u><span style='color:#1F497D'><o:p></o:p></span></p>
</div>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<div>
<div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'>
<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span
style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>
bldg-sim-bounces@lists.onebuilding.org
[mailto:bldg-sim-bounces@lists.onebuilding.org] <b>On Behalf Of </b>Sami,
Vikram<br>
<b>Sent:</b> Thursday, November 11, 2010 8:59 AM<br>
<b>To:</b> bldg-sim@lists.onebuilding.org<br>
<b>Subject:</b> [Bldg-sim] Is there a quick model for double skins facades?<o:p></o:p></span></p>
</div>
</div>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>We are doing a project in a pretty cold climate. The project
design has a really big glass façade facing south. One of the ideas to reduce
conductive heat loss is to create a double skin façade on the south side.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Now I realize that this is going to take a fair amount of
analysis work to design it properly. What I was wondering is if there is a
quick analysis tool/methodology to tell if this is even feasible to go into
more detailed analysis. <o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Any help would be much appreciated<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal style='text-autospace:none'><b><span style='font-size:9.0pt;
font-family:"Arial","sans-serif";color:gray'>Vikram Sami</span></b><span
style='font-size:9.0pt;font-family:"Arial","sans-serif";color:gray'>, LEED AP<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;
font-family:"Arial","sans-serif";color:gray'>Sustainable Design Analyst<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;
font-family:"Arial","sans-serif";color:gray'>1382 Peachtree St. NE, Atlanta, GA
30309<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:9.0pt;
font-family:"Arial","sans-serif";color:gray'>t: 404-443-7462
f: </span><span lang=ES style='font-size:9.0pt;font-family:"Arial","sans-serif";
color:gray'>404.892.5823 </span><span style='font-size:9.0pt;
font-family:"Arial","sans-serif";color:gray'> e:
vikram.sami@perkinswill.com </span><a
href="http://www.perkinswill.com/"><span style='font-size:9.0pt;font-family:
"Arial","sans-serif";color:gray;text-decoration:none'>www.perkinswill.com</span></a><span
style='font-size:9.0pt;font-family:"Arial","sans-serif";color:gray'><o:p></o:p></span></p>
<p class=MsoNormal style='margin-bottom:3.0pt;text-autospace:none'><b><span
style='font-size:9.0pt;font-family:"Arial","sans-serif";color:gray'>Perkins+Will.</span></b><span
style='font-size:9.0pt;font-family:"Arial","sans-serif";color:gray'> </span><span
style='font-size:9.0pt;font-family:"Arial","sans-serif";color:#ADD425'>Ideas +
buildings that honor the broader goals of society</span><span style='font-size:
9.0pt;font-family:"Arial","sans-serif";color:green'><o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><b><span style='font-size:8.0pt;
font-family:"Arial","sans-serif";color:gray'><img border=0 width=38 height=33
id="Picture_x0020_0" src="cid:image002.jpg@01CB817C.995DF2F0"
alt="75logo_only.gif"></span></b><span style='font-size:9.0pt;font-family:"Arial","sans-serif";
color:gray'>Years of Design Innovation</span><b><span style='font-size:8.0pt;
font-family:"Arial","sans-serif";color:gray'><o:p></o:p></span></b></p>
<p class=MsoNormal style='margin-top:3.0pt;text-autospace:none'><span
style='font-size:6.0pt;font-family:"Arial","sans-serif";color:gray'>This email
and any files transmitted with it are confidential and intended solely for the
addressee. <o:p></o:p></span></p>
<p class=MsoNormal style='margin-top:3.0pt;text-autospace:none'><span
style='font-size:6.0pt;font-family:"Arial","sans-serif";color:gray'>If you are
not the named addressee you should not disseminate, distribute, copy, or alter
this email.<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:6.0pt;
font-family:"Arial","sans-serif";color:gray'><o:p> </o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><b><span style='font-size:6.0pt;
font-family:"Arial","sans-serif";color:gray'>Please consider the environment
before printing this email.<o:p></o:p></span></b></p>
<p class=MsoNormal> <o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
</div>
</body>
</html>