How to attach solar panel to fiberglass roof?

[TimLoon]

I have set up my first solar panel wiring and controller and now am ready to attach the (1) 100 watt panel to the fiberglass roof of my motorhome. The system came with self drilling screws with fine machine type threads. Of course, no instructions saying that's what they are for. I am more inclined to use stainless pan head wood screws into properly drilled and countersunk holes. I have Dicor for waterproofing. Any guidance as to what worked for other folks? Thanks, Tim

[TimLoon]

Just spoke to my brother who works for 3M. He installed his solar panel with 3M- VHB tape. He said it is used for installing windows in sky scrapers. Guess I will give that a try.

[newmar10]

wood screws and Polley butelane tape works the best. I have put to 180 watts on my dutch star Probably not spelled right

[michelb]

FWIW, I've seen tons of places that say that on a fiberglass roof, all you need is 3M VHB tape. I don't love the idea of drilling unnecessary holes in the roof so I'm going to try that when I get around to mounting my panel.

[mikebreeze]

I'm going to install a 7 watt trickle charger solar panel on my roof using VHB tape. However, I still have to figure out how to get the wire from the solar panel either down to my RV battery or first to my control panel where I will install an indicator, then to the battery. I was hoping to fish the wire through the air conditioner. However, I may end up drilling a hole in my rubber roof.

[TimLoon]

Got a roll of 1" wide 3M-VHB tape. Laid the panel on the roof and marked out the 4 mounting pads. I cleaned the roof and pads with denatured alcohol and mounted the panel. My brother was right when he said "you betta get it right the first time". This stuff really sticks. Just to be sure, I then covered the mounting pads with Eternabond tape. I think the fiberglass roof will tear before the panel gets loose. Solar Panel was cranking today even with overcast skies.

[alv3769]

i mounted mine with 3m vhb tape. did not want to put holes in the roof. very strong mounting, i tried to pull them off after install and would not budge, great stuff

[Ray,IN]

Originally Posted by mikebreeze

I'm going to install a 7 watt trickle charger solar panel on my roof using VHB tape. However, I still have to figure out how to get the wire from the solar panel either down to my RV battery or first to my control panel where I will install an indicator, then to the battery. I was hoping to fish the wire through the air conditioner. However, I may end up drilling a hole in my rubber roof.

My solar wiring runs through the refrigerator roof vent, down into the coach. My refrigerator is not far from my house battery bank, which makes running the wiring easier. I plan to add about 140-200 watts this fall before we head out to Key West for a month.

[bobmac]

I just mounted two 100w panels on the roof of my Journey. I wanted a very secure mount but with the capability of removing the panel. I used 1/8" x 1.5" angle aluminum. I used an 8" piece to attach to the base of each corner of the panels with 1/4" nuts/bolts and a 5" piece to mount on the roof. Before mounting, I drilled a hole thru the center of the vertical pieces and attached them with a 1/4" bolt. This allowed the base to swivel slightly to conform to the shape of the roof. I glued the 5" roof mounts using 3M 5200 adhesive to the roof and used 2 #10 SS screws on the ends of each roof mount and covered them with caulking. It is a very secure mount.
The panel supplier offered four 1.5" wide SS "Z" mounts to secure the panels that used a single screw each. I felt these were inadequate even with an adhesive as the load can be significant at highway speeds on a windy day. There is also a 1 inch plus air space under the panels that "helps cool the panels to increase efficiency" and allows water on the roof to drain easily.
Good luck,

[TimLoon]

Did a weekend trip to a local campground (30+ miles). Panels hung tight even in 95 degree temperatures. Will check again after the next longer trip.

[SlyFox]

I have run by this post and am curious on the long term effects to the 3M VHB tape. I see it has been a couple of years ago that this post was active, so how has the 3M VHB tape stood up for you since then? Are your solar panels still holding tight?

[superlucky]

The tape is great. I put Dicor self-leveling over it just to protect it.

This tape is incredible.

Bill

[pasdad1]

Originally Posted by SlyFox

I have run by this post and am curious on the long term effects to the 3M VHB tape. I see it has been a couple of years ago that this post was active, so how has the 3M VHB tape stood up for you since then? Are your solar panels still holding tight?

I watched a show on television showing how they built the worlds tallest skyscraper in Dubai and the glass windows are held in place with only the VHB tape! No screws or other mechanical fasteners.


This pdf also shows many other fantastic ways VHB is being used.

http://multimedia.3m.com/mws/media/3...er-booklet.pdf

[TimLoon]

Was up on the roof a couple of weeks ago. Panel is still tight and do not see any reason to redo. Found I use the 3M VHB tape for lots of applications. Great stuff!