[RE-wrenches] Roof flashings on L-feet in high snow load conditions

[Ray Walters]

Thanks for the pitch info, very helpful.  Are you using a heavy wall 
thickness on the pole?   I thought with DP &W we could only go 6 ft out 
of the ground without increasing the pole size or adding bracing.

Ray

On 11/13/2012 4:21 PM, toddcory at finestplanet.com wrote:
>
> ray,
>
> this has been a learn by trial and error learning experience. i know 
> 12/12 is ok and 5/12 is not... so somewhere in between those two pitch 
> angles there is change.
>
> the latest pole mount i did was a dpw rack with 3 kW on an 8" pole. i 
> am attaching a 100 kb pix of this monster!
>
> todd
>
> On Tuesday, November 13, 2012 11:12am, "Ray Walters" 
> <ray at solarray.com> said:
>
> HI Todd;
>
> That's very interesting.  What roof pitch does that happen? I'm 
> guessing that at a step enough tilt, the frame damage is alleviated?
> Also on your tall pole mounts what pole design do you use? I've tried 
> telescoping type, and guy wires on tall poles.
>
> Ray
>
> On 11/13/2012 12:08 PM, toddcory at finestplanet.com wrote:
>
>     I have never had good results with roof mounted pv in our heavy
>     (mount shasta) snow area. the snow tends to creep down the glass
>     and peel the bottom of the frame off the module... and then the
>     glass breaks as it has no support in that area.
>
>     so, around here... i do pole mounts.... WAY up in the air.
>
>     todd
>
>     On Tuesday, November 13, 2012 8:04am, "Troy Harvey"
>     <taharvey at heliocentric.org> said:
>
>     Hi all,
>     We have been doing PV installs for years with L-feet and silicone
>     without problems ever. Even still, gravity flashings seem
>     attractive in shingle roofs, to provide a second level of
>     security, and a more professional install (at least in
>     perception). But the cost of these systems in significant in high
>     snow load areas where we often have L-feet every 2 feet on center,
>     to evenly load the structure below. In todays costs, the feet
>     could cost as much as 33% of the panel value.
>     I'm wondering what other people are doing in high snow load areas?
>     Also. I have noticed that there is a flip side to the risks. We
>     have found that unless you have good quality shingles, on a
>     preexisting roof, that sometimes the adhesive sticking the
>     shingles together is stronger than the low quality shingles
>     themselves - adding risk of trying to shoe horn flashing in after
>     the fact. Your experience?
>
>     thanks,
>
>     Troy Harvey
>     ---------------------
>     Principal Engineer
>     Heliocentric
>     801-453-9434
>     taharvey at heliocentric.org <mailto:taharvey at heliocentric.org>
>
>
>
>
>
>     Sent from Finest Planet WebMail.
>
>
>     _______________________________________________ List sponsored by
>     Home Power magazine List Address:
>     RE-wrenches at lists.re-wrenches.org Options & settings:
>     http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
>     List-Archive:
>     http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
>     List rules & etiquette: www.re-wrenches.org/etiquette.htm Check
>     out participant bios: www.members.re-wrenches.org
>
>
>
>
> Sent from Finest Planet WebMail.
>
>
> Sent from Finest Planet WebMail.
>
>
> _______________________________________________
> List sponsored by Home Power magazine
>
> List Address: RE-wrenches at lists.re-wrenches.org
>
> Options & settings:
> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
>
> List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
>
> List rules & etiquette:
> www.re-wrenches.org/etiquette.htm
>
> Check out participant bios:
> www.members.re-wrenches.org
>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20121113/6160472f/attachment-0003.html>