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Cool roofs work to reduce the cooling load. For uncooled
warehouses, the cool roof serves to increase heating costs.
<br><br>
In southern Ontario, I have seen very few projects, with mechanical
cooling, where there is a net gain in energy savings when examining
"cool" roofs as an ECM. In most cases, the extra cost for
the reflective roof does not have a viable payback. <br><br>
At 01:11 PM 09/06/2012, Nathan G wrote:<br><br>
<blockquote type=cite class=cite cite=""><font size=2><b>All,<br>
</b></font><br>
<font size=2><b> <br>
</b></font><br>
<font size=2><b>We need to model a cool roof ECM on an industrial
complex.<br>
</b></font><br>
<font size=2><b>I have researched the archives and did not find any
guidance how to accommodate the cool roof properties.<br>
</b></font><br>
<font size=2><b> <br>
</b></font><br>
<font size=2><b>As a preamble lets me briefly describe how cool roof is
characterized:<br>
</b></font><br>
<font size=2><b> <br>
</b></font><br>
<font size=2><b>Cool roof thermal properties:
<ol>
<li>Solar Reflectance</b></font>
<li><font size=2><b>Thermal Emittance.</b></font>
<li><font size=2><b>R-Value</b></font>
</ol><br>
<font size=2><b>A</b> <b>Cool Roof Minimizes The Solar Heat Gain</b>
<b>of a Building by</b> <b>First Reflecting Incoming Radiation,</b>
<b>Then by Re-emitting the Remaining Absorbed Portion.<br>
</b></font><br>
<font size=2><b>Sun radiation hits the roof, the fraction of solar energy
that is reflected by the roof is called Solar Reflectance (SRI), some
heat is absorbed by the roof and transferred to the building.<br>
</b></font><br>
<font size=2><b>The relative ability of the roof surface to radiate back
absorbed heat is termed Thermal Emittance. <br>
</b></font><br>
<font size=2><b>Cool roofs increases substantially SRI and TE<br>
</b></font><br>
<font size=2><b>As a Result, The Cool Roof Stays Cooler than a
Traditional Roof of Similar Construction. <br>
</b></font><br>
<font size=2><b>Some cool roof products also has a layer of additional
insulation<br>
</b></font><br>
<font size=2><b> <br>
</b></font><br>
<font size=2><b>eQUEST currently has only R-Value to specify<br>
</b></font><br>
<font size=2><b>Can someone please advise how can we take into account
the SRI and TE as well<br>
</b></font><br>
<font size=2>Thanks,<br>
</font><br>
<font size=2> <br>
</font><br>
<font size=2 color="#000080"><b>Nathan Guedalia, CTO<br>
</b></font><br>
<font size=2 color="#000080"><b>Equidex Energy<br>
</b></font><br>
<font size=2 color="#000080"><b>P.O. Box 566<br>
</b></font><br>
<font size=2 color="#000080"><b>41 King Place<br>
</b></font><br>
<font size=2 color="#000080"><b>Closter NJ 07624<br>
</b></font><br>
<font size=2 color="#000080"><b>Tel: (201) 306 0660<br>
</b></font><br>
<font size=2 color="#000080"><b>Fax: (201) 784-0854<br>
</b></font><br>
<font face="Calibri"> <br>
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<x-sigsep><p></x-sigsep>
>><br>
Christopher Jones, P.Eng.<br>
Suite 1801, 1 Yonge Street<br>
Toronto, ON M5E1W7<br>
Tel. 416-203-7465<br>
Fax. 416-946-1005<br>
email cj@enersave.ca<br>
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