Solar roof installation?

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My electrician hasn't a clew, the panels have no instructions, and the only prof. solar installer in Louisiana is in NO. and the books on solar do not address this. I have some aluminum rails that I would like to place on a standard asphault shingle foam-plywood panel roof that is coincidentally perfectly placed for solar installation. You folks that have been there, do you drill and screw directly on and through the shingles? Use flashing? :-(

Thanks! -mostly a lurker who has learned alot from you all-

-- Wm McBride (mcbri29@attglobal.net), November 24, 1999

Answers

Maybe Mr. Solar knows...

http;//www.mrsolar.com

-- j werner (jwerner15@hotmail.com), November 24, 1999.


I decided to put my panels on the hillside
behind the house because I don't like putting
holes in the roof. It rains a lot here. If
you need to put the panels on the roof follow
these steps. Find where the rafters are by
looking under the eve. By line of sight and
with the help of another person snap a line
where you think the rafter might be. Check
with a nail before drilling. If you missed
pull nail using plywood to protect the roofing.
Fill hole with blackjack. When you have the
correct spots drill with a bit that is the
size of the shank of your lag screw. Fill hole
with blackjack just before assembly. Use spacers
to keep the panels from stopping the flow of
water. Attach firmly so that winds don't blow
the panels off.

-- spider (spider0@usa.net), November 24, 1999.

You need spacers for two reasons: 1) as spider says, so you don't dam the rain runoff; 2) more importantly, you must have air circulation under the panels. Without circulation, excessive heat will build up and a) degrade the performance of the panel; and b) shorten its lifespan.

Probably 2x4 spacers will work fine, getting panel at least 1 1/2" off roof.

-- Mr. Bob (thebobster@delphi.com), November 24, 1999.


Well, we tend to hate seeing PV panels on roofs; it's hot up there, hard to get to to clean panels and or check/tighten connections. My personal favorite is the top-of-pole mount on a ground mounted pipe, adjustable for azimuth and elevation. You might want to adjust "off- south" if you have more sunshine in the afternoon than morning or vice versa....and you should have seasonally adjustable tilt (adjust 3X year gives about 15% improvement)

Check out the mounts at this site to see what I mean (they do make good products too) http://www.2seas.com/menufr.htm

There are some articles on PV angle settings in the download section of our website at http://www.homepower.com. These are PDFs of articles we've run in the magazine (also available on CDROM).

-- Don Kulha (dkulha@vom.com), November 24, 1999.


I would NOT put the panels on the roof!!

Not only is the installation difficult, you can't tilt them to maximize their output as the seasons change.

Also, there is routine maintenance and climbing on the roof for that adds to your troubles.

Regards,

Will

-- Will Huett (willhuet@usa.net), November 24, 1999.



I wasn't clear. I've perused the Mr Solar site which was helpful but didn't help me here. I have chosen the roof as we are located in dense woods and would have to do alot of clearing to place them on the ground. The panels are easily accessible by standing on a porch roof which is of less pitch. The aluminum rails came with the panels to lift them off the roof. The roof is standard shingle on chipboard/foam/chipboard panels 5" thick without rafters. There are large beams underneath without an attic- The roof is the ceiling. It is "timber frame" construction. The beams are very far apart. My question is - I can just attach the rails directly on the shingles in a vertical direction to allow for water shedding to the roof by screwing into the chip board through the asphalt shingle using a sealer to prevent leaks? Or perhaps mount them on oneside along and into one of the beams using some 10" screws for extra strength? Hmmmmm, I'm talking myself into it. Any Ideas? Thanks!!!

-- Wm McBride (mcbri29@attglobal.net), November 24, 1999.

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