Solar Panel Install

tim myers · 06-06-2022, 10:03 AM

I saw the other Solar Expansion thread, but thought this should be a new topic. Mods feel free to merge the two if you think that is best.

I am in the planning stages for adding solar panels to the roof of my Journey, being I have laid things out and feel I can fit 8 panels at 200W on the roof and still have maneuvering space to walk around on the roof.

My question is two fold.

1. How do I anchor the panels to the roof structure? Unless I got lucky and caught one of the sheet metal trusses, most of the panels will be fastened through Filon and a 1/8" piece of luan board. Do these solar panels catch the wind as you are driving down the road? Thoughts?

2. Do others remove or swing these panels out of the way to gain access to the roof for annual or semi annual cleaning of the roof?

I don't want to gain solar and loose my roof!!!

**creativepart** · 06-06-2022, 11:25 AM

Most of us that screw the panels down just use slilicone caulking under the mounts, screw the mount through the caulking and thoroughly cover the top side of the mount screws and all. I used short but hefty wood screws. I never even attempted to find any trussing... if there is any. And I've had zero issues with wind or travel. They are still firmly in place 4 years down the road.

Many skip the screws and use high adhesive tape called VHT. I suppose that works just as well. Folks just need to prep the area well where the tape will be adhered to the roof. I've had VHT tape fail in other areas holding other things. But I'm sure I didn't do much prep at all.

I don't ever remove my panels. I just clean around them.

tim myers · 06-06-2022, 11:35 AM

thanks for the information

Lv2Roam2 · 06-06-2022, 02:02 PM

AM Solar did my installation 7 years ago - good info on their website. They adhere the panels with VHT and then cover the mounting foot with Dicor on a fiberglas roof - no problems during our full time travels with panels raised about 1 1/2" off the roof. For a rubber roof screws may be the best way to proceed. I use extension arms to raise one side of the panels to clean, angle to the sun when parked, etc.

http://amsolar.com

spierce617 · 06-06-2022, 04:15 PM

In this video Tito installs solar with no drill into the roof of his 2002 Winnebago Adventurer. It seems like a good install.

https://www.youtube.com/watch?v=uvMY...=RVwithTitoDIY

dajo · 06-06-2022, 04:37 PM

What is VHT tape? Anyone have a link?

spierce617 · 06-06-2022, 04:48 PM

Quote:

Originally Posted by dajo

What is VHT tape? Anyone have a link?

I think he means VHB tape.

https://www.3m.com/3M/en_US/p/c/tapes/foam/vhb/

dajo · 06-06-2022, 04:53 PM

Quote:

Originally Posted by spierce617

I think he means VHB tape.

https://www.3m.com/3M/en_US/p/c/tapes/foam/vhb/

66 choices which one works for solar panels?

spierce617 · 06-06-2022, 05:39 PM

Here is the tape that Tito used in his video.
https://www.amazon.com/gp/product/B0...language=en_US

dajo · 06-06-2022, 06:56 PM

Quote:

Originally Posted by spierce617

Here is the tape that Tito used in his video.
https://www.amazon.com/gp/product/B0...language=en_US

Thank You

lenore · 06-07-2022, 08:41 AM

I just used this method on Rubber roof, but didnt feel comfortable because the rubber can lift from the Luan under the TPO roof. So I used a combination of VHB tape and used Well nuts for locking the T track with 3 screws each rail. Just did a 700 miles trip and everything is secure with Regular Renogy Solar panels that are replacing my flexible Sunpower panels. Better cooling. I also put a lip on lead edge of panel to prevent lift from front and T track prevents lift from sides. The well nuts are brass nuts embedded in rubber that expand under the wood of the roof, very secure, the old screw the flexible panels to roof has been an issue with many loosing their solar panels while on the road. Tito's mounting is great on non-rubber roof but I wanted extra insurance. I used stainless steel hardware for everything to prevent rapid rust.

tim myers · 06-07-2022, 08:01 PM

All great information, I will save this thread for future use.

JD4x4 · 06-08-2022, 06:09 AM

I've only mounted 1 100W panel so far about a year ago & I only used VHB. No issues at all but I cleaned the heck out of the mounting areas with alcohol.
https://www.amazon.com/gp/product/B00GTAJMAO

BobC · 06-08-2022, 10:24 AM

By using VHB tape alone, you're counting on the adhesive between the 1/16" Filon roof and the 1/8" Luan plywood to hold. With age, this seems to deteriorate in spots so my choice would be to use both VHB tape and screws, perhaps with "rubber well nuts" for added security.

https://amsolar.com/blog/mounting-pa...-thin-surfaces

Marine359 · 06-08-2022, 03:14 PM

Since you can’t glue or tape hard panels to a rubber roof, the only good option is screwing them to the roof. I’m ready now to mount 2x 200w to my MM roof, but I’m scared of putting screws through the roof. Has anybody reading this thread used the well nut mounting method? In researching, I’m told the the best professional installers use well nuts on rubber roofs. I watched this video and now I’m curious if this is the best, safest, and most waterproof method:

https://youtu.be/q4_QOihntPY

BobC · 06-08-2022, 04:00 PM

Quote:

Originally Posted by Marine359

Since you can’t glue or tape hard panels to a rubber roof, the only good option is screwing them to the roof. I’m ready now to mount 2x 200w to my MM roof, but I’m scared of putting screws through the roof. Has anybody reading this thread used the well nut mounting method? In researching, I’m told the the best professional installers use well nuts on rubber roofs. I watched this video and now I’m curious if this is the best, safest, and most waterproof method:

https://youtu.be/q4_QOihntPY

I used them on a Nash TT that I used to own without any problems. You need to make sure they're the proper length the plywood decking of your roof. On my second Nash, for no particular reason, I just used screws, making sure that the front screws went into a wooden rafter. In both cases my plywood decking was about 3/8" thick. Thinner decking would definitely warrant the use of well nuts. You need to make sure that the well nuts are matched to the thickness of your decking. In drilling the holes, make sure you don't drill them larger than specified or the well nut will spin while being installed. Should you accidentally do so, you can partially expand the well nut by starting the installation process before inserting it into the hole.

https://www.mcmaster.com/well-nuts/

Marine359 · 06-08-2022, 04:13 PM

Can you remember what size you used?
Is 1/4” - 20 the best size? I suppose grip depth is dependent on roof thickness.
Did you still feel it necessary to install lanyards?

BobC · 06-08-2022, 04:37 PM

Quote:

Originally Posted by Marine359

Can you remember what size you used?
Is 1/4” - 20 the best size? I suppose grip depth is dependent on roof thickness.
Did you still feel it necessary to install lanyards?

You are correct, the roof thickness is the most important issue. In choosing the length of the well nuts, I'd opt for something that puts my roof thickness in the middle of the grip range according to the site I provided earlier or by the manufacturer of whatever you buy if different. It was years ago so I don't remember what size threads I used. My current roof is about 3/16" or 0.1875" thick. I'd probably use 1/4" - 20 now but I'm pretty sure that 10-32 would be adequate. If I was concerned, I could just use an extra well nut per bracket.

I don't know what you mean by lanyards, some sort of safety tether? If so, no, I didn't use them. There's really not as much force on the panels as we might suspect. If there were, our forums would be awash with horror stories of panels flying off, and they're not. My panels were 100W panels that I installed back in 2005 or 2006 so they were larger and heavier than today's panels.

Marine359 · 06-08-2022, 05:03 PM

Guess I was overly afraid of a panel flying off and killing somebody. To be on the ultra-safe side, I’ll probably use lanyards, but there’s really no secure place to attach them, except maybe the mounting screws for the A/C cowling.

BobC · 06-08-2022, 06:35 PM

Quote:

Originally Posted by Marine359

Guess I was overly afraid of a panel flying off and killing somebody. To be on the ultra-safe side, I’ll probably use lanyards, but there’s really no secure place to attach them, except maybe the mounting screws for the A/C cowling.

Why would those screws be more secure, especially if subjected to a sudden load from a flying panel? It seems like you'd be better off having the lanyard encircle the AC. Another thing you could do would be to fashion an "air dam" to deflect air over the front edge of the panel rather than have it get underneath.