<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=us-ascii"><meta name=Generator content="Microsoft Word 12 (filtered medium)"><base href="x-msg://5/"><style><!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@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";}
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;}
span.apple-style-span
{mso-style-name:apple-style-span;}
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]--></head><body lang=EN-US link=blue vlink=purple style='word-wrap: break-word;-webkit-nbsp-mode: space;-webkit-line-break: after-white-space'><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>All excellent points, John. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Concerning difficulty in air sealing to this level, I saw some great examples of using the structural sheathing layer as the air barrier when I was at the PH conference in Portland, OR this year, sure seems to be a better way than poly and tape and acoustic sealant for getting 3X tighter than R-2000. Freaks out some building officials though.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I should clarify my issues with HOT2K to say the problem is really the EnerGuide Rating System, which is something NRCan is well aware of and in the process of changing. You might find that despite your best efforts it’s pretty hard to get to an 88, but if you manage that extraordinary feat I bet you’ll never get to an 89 without a heat pump (and what do these rating numbers really mean?). HOT2K is actually a pretty good modeling tool, particularly in General mode when you can over-ride the program-specific defaults and assumptions.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Thanks for the great debate, I think we can both agree whatever gets more really efficient homes on the ground is a good thing.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Ross Elliott<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";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"'> jfstraube [mailto:jfstraube@gmail.com] <br><b>Sent:</b> Tuesday, January 25, 2011 10:27 PM<br><b>To:</b> relliott@homesol.ca<br><b>Cc:</b> 'Green Building'<br><b>Subject:</b> Re: [Greenbuilding] first certified Passive House in Canada<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I like 0.6@50 too, but it takes a lot of effort to achieve, and this may not always be justified. If I can get it, in cold Canada, I will take it every time. But if I only get to 0.9, then the house can still use the same energy as a PH with some other modifications.<o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>I also hear that the reason for the 0.6 is to limit condensation (would it not be nice to have this documented somewhere other than in interviews with Herr Feist?). <o:p></o:p></p></div><div><p class=MsoNormal>However, if I design a wall properly, say placing half the insulation value outside of the wood framing, and use a ventilated space behind the cladding, it is essentially impossible to get condensation, even with, say, 2 ACH@50. So if condensation control is the goal, we have the science and experience to support alternate methods of achieving that goal. The frost balls on the outside are not harming anything and we have many years of experience to show that R2000 airtightness has licked the condensation problems in climates much more severe than Germany.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>If energy saving is the issue of air tightness, then trade-offs between other components of the building should be allowed: it should be rolled into the energy target. There needs to be a limit to avoid comfort problems and IAQ problems: likely this is in the 1.5 to 2.5 range depending on climate. But the energy and condensation reasons are not technically supportable.<o:p></o:p></p></div><div><p class=MsoNormal>R-2000 air leakage limit is 1.5@50. Thousands have been built. We can do it. Thousands of homes have been built to 0.6. We can do this. The question is, how much work and how worth it is it? <o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>This is the type of conversation that is needed. 0.0 ACH@50 is nice and good, 0.5 is better than 0.6. Why 0.6 and not 0.7 or 1.0. If people are to follow the standard, there should be a good reason for the number or it should not be a hard requirement.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Can you point me to more information on how HOT2K does not handle high performance homes? It was developed based on careful comparisons with real houses in the Canadian climate with Canadian occupants, and has worked well in my experience. I would like to see more of the problems you or others hace identified (and I bet NRCan would like to have some real info on this too) since I dont know of them. Many are using HOT3000 to get more accurate solar DHW and thermal mass feedback, although I would use WUFI PLUS (a German program with very good detail) to truly capture thermal mass. My retrofit house has an ERS rating of 86, which I achieved without a ground source heat pump, and with some changes I made this last year, I bet I would get 88 now.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I like the open-source PHPP, but to make it this open they made a lot of simplifications and assumptions that limit its accuracy. It is fine in my books (I have my own set of spreadsheets I use, but they are based on hourly weather data, not monthly), but it is not correct to say it is more sophisticated, or more accurate, or more advanced (I have all claimed) than many other programs out there being used to design high performance houses. Check out the CEPHEUS 100 house study: predictions varied around measured by +/-50% like most prediction programs.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span class=apple-style-span>The Net Zero homes should not use "exorbitantly expensive renewable energy systems" to reach zero. Please look into them in some more detail. For example, some of them have R100 roofs and R70 walls and ACH around 0.5. They compared the cost of insulation or the cost of heat pumps or the cost of renewable energy systems and tried to choose the least cost path to optimization. Adding R20 of foam to an R20 foam slab (which seems common to some PH designs) is more expensive than using PV at market prices to save the same amount of energy that could be generated by the PV. Adding $10000 of insulation to say $250 PV can be wastefully deployed. Insulation and airtigtness and windows can be wastefully deployed. Todays PV systems will likely have the same lifespan or more than the glazing in the windows so I dont get the "obsolete" comment.</span><o:p></o:p></p></div><div><p class=MsoNormal><span class=apple-style-span> </span><o:p></o:p></p></div><div><p class=MsoNormal><span class=apple-style-span> I dont think PH's sole emphasis on insulation and airtightness is necessarily the right philosophy: nor do I believe Net Zero is the best way. I am sure that PH is not perfect and should be open to explaining its reasoning better than it does, and be more flexible to local climate and practise. </span>You, Ross, are one of the level headed PH advocates who is willing to admit "PH is not the answer to everything", which makes this an enjoyable exchange.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>John<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div></div></div></body></html>