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<font size=3>Jim:<br><br>
Regarding comp roofing: In the past, the mantra has been
"surface area." The concept was to have as much flat
surface of a mounting foot as possible in contact with the roofing.
This surface to surface contact area was filled completely with the
highest quality sealant we could find and never did we have a leak.
We satisfied this with a 3"X3" angle foot.<br><br>
As I get older, I have moved towards improved roof attachments. We
used to simply put aluminum feet directly on comp roofing, but we have
not done this for the last year or so. In an era when we have more
and more sub-par competition, it seems counter intuitive to increase
installation costs, but the more I learn the more I feel compelled to
avoid liability.<br><br>
Fast forward to today: For comp roofs, we have used the Thompson
technologies Flatjack
<a href="http://www.thompsontec.com/products/flatjack.html" eudora="autourl">http://www.thompsontec.com/products/flatjack.html</a>
and we are pretty enthusiastic about them. Also, we are more likely to use a DPW Power post flashed with an Oatey flashing. On flat roofs we have developed a technique of using an Oatey with an overlayment. On flat tile roofs we are 100% DPW Power Post and Oatey wide base flashings. For barrel tile, we use a wide based malleable aluminum flashing over the Power Posts.<br><br>
There are posts out there that have only one lag hole, but the DPW holds two lags. Speaking of lags, we used to use standard lags, now we use exclusively Simpson hot dip 1/4 X 3 rated lags.<br><br>
The bottom line is we can only sell our installation services to customers that can appreciate an emphasis on quality. It means we miss a lot of quotes, but I'm not willing to risk insurance claims.<br><br>
I hope this answers your questions.<br><br>
William Miller<br><br>
<br><br>
At 08:40 AM 1/23/2009, you wrote:<br>
</font><blockquote type=cite class=cite cite><font face="arial" size=3>Wrenches<br>
I know this issue has been pretty well hashed over on this site but I see a trend that I'm not sure how to relate to. The number of roof mounted PV structure mfgrs is on the rise and many are migrating to the US market from elsewhere. <br>
The trend now seems to be to drill thru the 3-tab shingles, tiles etc and into a rafter. Then drive home a threaded lag bolt with a patch of sealant on the exposed surface and covered by a large flat metal washer. Of course most all the mfgrs will offer an optional flashed version of attachment. <br>
So has the technology of sealants improved to a point that only a dollop is needed or is this just an adaptation of a European product coming here with hopes that it will work in this market as well as it does there. <br>
And how much of new products is simply cutting costs by reducing the amount of materials needed. <br>
</font> <br>
<font face="arial" size=3>Thanks as always<br>
Jim Duncan<br>
North Texas Renewable Energy Inc<br>
817.917.0527<br>
<a href="mailto:ntrei@earthlink.net">ntrei@earthlink.net</a><br>
<a href="http://www.ntrei.com /" eudora="autourl">www.ntrei.com </a><br>
</font><br>
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