building on John S's comments...<br><br>...are there some semi rigid strips of something like neoprene that could be applied over the outside face of the z-bars, that would have sufficient resistance to compression to support the cladding yet still provide some thermal breakage before the cladding is attached? this assumes that the potential for heat loss through the bridges is so great that even the addition of R-0.5 btwn bars and cladding would be significant.<br>
<br><br>AA<br><br><br><br clear="all"><b style="color: rgb(0, 102, 0);">Alan Abrams</b><b style="color: rgb(0, 102, 0);"><br>Abrams Design Build LLC</b><br style="color: rgb(0, 102, 0);"><i style="color: rgb(0, 102, 0);">A sustainable approach to beautiful space</i><br style="color: rgb(0, 102, 0);">
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<br><br><div class="gmail_quote">On Thu, Nov 11, 2010 at 11:02 AM, J Messerschmidt <span dir="ltr"><<a href="mailto:John@fourpointscg.com">John@fourpointscg.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
<div bgcolor="#ffffff">
<div><font size="2" face="Arial">Hi Thomas,</font></div>
<div><font size="2" face="Arial">I love the suggestion of taping the seams and
taping the board to z bars. With the air leakage to the outside eliminated
that would bring us a lot closer to the r-10, and it would be a proper drainage
plane. My concerns are, what kind of tape and how does water escape if it
does get in? 2" of xps has permeance of .55. Will that allow
vapor to escape? What about bulk moisture? Behind the xps is a
liquid applied membrane that probably has a very low permeance, so it has to dry
to the outside. </font></div>
<div><font size="2" face="Arial"></font> </div>
<div><font size="2" face="Arial">Lastly, looking at the interior wall assembly, if
the open cell foam has a perm rating of 8, and 1" of polyiso has a perm of
2.33, this could be a well insulated wall and will still dry to the
inside. Right? Unless I'm missing something, we'd end up with
about an R30 wall. I'd be very happy with that. What do you
think? </font></div>
<div><font size="2" face="Arial"></font> </div>
<div><font size="2" face="Arial"></font><font size="2" face="Arial"></font> </div>
<div><font size="2" face="Arial">Thanks!</font></div>
<div><font size="2" face="Arial"></font> </div>
<div><font size="2" face="Arial">John</font></div>
<div><font size="2" face="Arial"></font> <br></div></div></blockquote></div><br>