Mounting Solar Panels to Roof ?

[Dean & Mary]

I am looking for a secure method of mounting two 24 x 50 inch solar panels to the roof of my Bigfoot travel trailer.

Basically, I want it to look good, not cause a leak and not blow off while traveling.

What have you seen work or fail? Thanks, Dean

[peterh]

I am looking for a secure method of mounting two 24 x 50 inch solar panels to the roof of my Bigfoot travel trailer.

What have you seen work or fail?

I discarded the old frame for my 13x48 inch solar panel and built a new frame out of weather-resistant composite trim lumber that conformed to the shape of my trailer's roof. I made cardboard templates to test-fit the ribs before cutting the more expensive lumber, put a small radius on the downside edges to eliminate a sharp-edge stress point on the roof, assembled my new frame without the solar panel in it, test fit it again and drew the rib layout on the roof with a Sharpie, drilled holes through, re-assembled the frame with the panel in it doped the underside of the ribs with marine caulk and mounted it using stainless steel screws from the inside of the trailer. There's a topic showing how I did it.

[Morgan]

[quote]I discarded the old frame for my 13x48 inch solar panel and built a new frame out of weather-resistant composite trim lumber that conformed to the shape of my trailer's roof. I made cardboard templates to test-fit the ribs before cutting the more expensive lumber, put a small radius on the downside edges to eliminate a sharp-edge stress point on the roof, assembled my new frame without the solar panel in it, test fit it again and drew the rib layout on the roof with a Sharpie, drilled holes through, re-assembled the frame with the panel in it doped the underside of the ribs with marine caulk and mounted it using stainless steel screws from the inside of the trailer. There's a topic showing how I did it.


Attachment 14158


Peter,

You might want to re-think your mounting method. PV panels should have free air flow underneath to carry away excess heat. If it's as it appears, your method seals the area under the panel. That will significantly shorten the life of the panel.

[peterh]

Peter,

You might want to re-think your mounting method. PV panels should have free air flow underneath to carry away excess heat. If it's as it appears, your method seals the area under the panel. That will significantly shorten the life of the panel.

The side rails of the panel frame don't actually touch the trailer roof and sides, so as long as they don't get clogged with debris there should be circulation underneath, but thanks for mentioning that.

[brian m.]

See if this link gives you any ideas:

http://www.casitaclub.com/forums/index.php...+panel+mounting

He used 3M brand VHB tape to mount his panel permanently to the roof of his Casita.

[Lisa H.]

If you google "solar panel mounts" you will find a variety of products and resources that will inform and assist you in your quest.

Good luck!

[Dean & Mary]

A thanks for the quick reply’s & please keep them coming.

I have the mounts/brackets that came with the kit. Using those brackets I will have the recommended 2 inch spacing underneath each panel. Right now I plan on using 6 brackets for each panel.

The main question is how to attach the bracket to the fiberglass. Brain, I found the link to the Casita forum very useful - thanks. Basically, he just used “3M 4941 1/2"X36 YD VHB TAPE for $53.00 from Uline” and it is working. I am not that trusting of just tape over the long haul. I could use tape on all 6 mounts, but just drill the 4 corners? Probably a good compromise. If I drill a hole for a screw, what product is good for sealing the entry point?

[Lyle Brunson]

The West Marine catalog has a solar panel mounting kit that employs Sikaflex 252 adhesive.

A flexible single part adhesive like that might be better than through fastening in terms of leak resistence. I'd think you'd want to test it though, to make sure you had confidence in it in that application, but it should glue just about anything to ...well...just about anything.

[Dean & Mary]

I found the Sikafex 252 adhesive here http://www.westmarine.com/webapp/wcs/store...;classNum=10890

Looks like it will hold up to moisture very well since it can be used below water line.

However, the following was listed as part of its specification:

Material Incompatibilities: Acrylic plastics (ABS, Lexan)

[Dean & Mary]

Here is the link for the suggested 3M 4941 VHB Acrylic Foam Tape: Click here!

This looks like a great product. I will order the tape and then decide how many screws if any are needed. I just don’t like the idea of drilling holes in the roof nor do I like the idea of having the panels blow off because I didn’t use screws.

[David O.]

For those of you that are mounting your panels on the roof with tape.
What are you doing for the connection wire?
Drilling a hole seams to be the only option without a vent to run it through.
What you you using to seal the hole after running the wire, just sealing with sealant or using some type of compression connection.
I have a 2008 Out Back (Trillium). The roof is sloped to the back and not sure if I need to get the panel perfectly level or is it okay to go with the slope?
I was thinking about using the "sticky feet" but there is not enough adjustment on the back feet if I need to get the panel flat.
Any thought?

[The Minimalist]

Originally Posted by David O.

What are you doing for the connection wire?
Drilling a hole seams to be the only option without a vent to run it through.

David, you might try one of the through hull marine 'cable clam' fittings as shown here:

https://www.amazon.com/s/ref=nb_sb_n...k%3Acable+clam

I used the first one shown and filled it with sealer. It works fine and mine is mounted on the top where it begins to turn down to the front of the trailer. In that position, if it were to leak, rain would be driven in while driving. It doesn't.

I also like the looks of the SeaChoice thru hull fitting about half way down the page, but you would have to go through the hull in a location where the inner part would not be visible. With the side entry cable clam, I turned the cable at a sharp right angle where it entered and ran it behind the rat fur.