Framework for roof mounting solar

[EZ Generator Switch]

My 24F four winds came ready for solar but no panel on roof. For now since it came with a 10 amp 12 volt controller I can't exceed 150 watt panel. Looking into mounting some aluminum unistrut on roof in case I want to add more panels in the future , should I need it. A) has anyone here mounted panels and if so do you know the roof structure layout regarding studs? I have searched it can not find anything B) any recommendations you might have.
Thank You

[EA37TS]

Go to the Thor owner’s resource site and download the structural diagrams for your coach. You can also contact Thor and they will send you the diagrams.

[MLP]

My independent RV repair used adhesive mount, and screws into the thin wood. Almost all are just screwed into the wood. Then Dicor over the screws and around the metal mounts. Six mountings per panel.

[DavidEM]

Don’t be limited by that puny GoPower controller. For about $150 you can buy a Renogy MPPT controller to replace the GoPower and it will support 500 watts of panels. It will also be 15% more efficient.

I wouldn’t build a Unistrut support structure. Just buy some L brackets and screw them to the thin plywood and Dicor over the screws.

David

[EZ Generator Switch]

Purpose of the unistrut is changing panels out, failure of panel, damaged panel or adding more panels. L brackets are good as long as nothing goes wrong.

[EZ Generator Switch]

No structural diagrams, sent Thor a e-mail. Thanks for the info...I printed out a lot of info, I'll just add to the THOR bag in case I need it.

[signguy71]

https://www.youtube.com/watch?v=uvMYv7afUWM

[Chateau_Nomad]

I have a 2020 Chateau 24F... sister product to the Four Winds.

Ours came with the exact same 10 amp PWM solar prep with the MC4 connector on the roof. In summer 2020 I installed two 100 watt Rich Solar panels - used the aluminum L brackets kits with included screws. I also replaced the 10 amp controller with a 40 amp MPPT controller from Rich Solar.

Note... As you're browsing panels and controllers on Amazon, notice how similar in appearance the cases are. That's because they come from the SAME FACTORY, then are rebranded by the seller. So... I suggest shop price.

Attention to detail, Eternabond tape and self leveling Dicor are key. I laid down a patch of Eternabond tape where each bracket foot contacted the roof. Then smeared a little Dicor on the bottom of the foot and pressed it onto the Eternabond tape... then drilled holes through the Eternabond tape into the roof plywood. Next dab a little Dicor onto each screw and drive it down flush... being careful not to over tighten and strip the threading in the wood. Follow that up with a coating of Dicor to cover each foot where the screws are. I have had ZERO issues over three seasons.

So... I'm now updating my entire solar/battery setup. I'm waiting on a string of sunny Ohio weather to remove the two 100 watt panels, and replace them with three 200 watt Rich Solar panels. Careful use of a sharp utility knife to cut the Dicor around each foot. Scrape the Dicor off the screw heads... then remove.

If the new panels don't exactly fit the previous layout, no worries... the holes get covered with Eternabond. The new panels install exactly like the old ones. Sure, there's likely going to be a few Eternabond patches covering holes, but so what? Waterproofing is key... not aesthetics. Nobody sees the roof!

[blw2]

I used a stud finder to verify drawings and locate the structure.

[BASSMAN]

Go with the glue down mounts from Renogy, you can buy them cheap on Amazon and no screws needed, I have 6, 100 watt panels on my roof and they have been there since 2017, as long as you get the right adhesive and the primer they will never come loose

[Ejohn2317]

I mounted mine to the roof just like Tito didn't use any screws just 3M industrial tape clean the roof real good hasn't moved in 4 years.

[CHS]

Just remember that if you glue down the brackets, they will only be as good as your roof material is glued to the roof. Your gluing to the fabric, NOT the wood below it. I remember watching videos of air getting under the front edge of the roof material and pulling up the roof right off the wood structure. IMHO, gluing to me is more for fiberglass type roofs.
I screwed mine into the wood. I looked at it this way. With all the antennas, vents, AC unit/s already installed, whats another few screws.

https://www.youtube.com/watch?v=HkODnhaVggU

[Ejohn2317]

I hear you the roof of my unit is fiberglass. I have experience with the 3M industrial tape it's actually used in construction to hold in Windows on the outside of skyscrapers. It's been up there now for 4 years and I do check it at least twice a year so far it hasn't moved. I did add a layer of ceiling tape when I first installed it more for sun protection here in Florida than anything else.

[Chateau_Nomad]

Finished removing my two 100 watt panels and installing three 200 watt panels. 200Ah LiFePO4 behind panels in storage (under bed). 3k inverter/charger. Removed factory converter in fuse panel to make room for battery monitor and remote inverter switch... just no other place to put those - did NOT want to run cables through a moving slide room!!

The only ones who see an RV roof are kids throwing rocks off freeway overpasses... and we try our best to avoid freeways when possible.

I'm no structural engineer, but I figure as tightly adhered as my panels are to the TPO, nothing's moving... OR leaking. There is a patch of Eternabond on the roof... the panel bracket is screwed (with a dollop of Dicor) through that... then covered with another patch of Eternabond.

After three years and no issues with the old panels, no reason to change my install method. The old holes are covered with Eternabond.

Next up... Give the roof a good scrubbing, and finish covering every drop of Dicor with Eternabond. AKA: "The Judge Eternabond challenge".

[taylorbob1]

Originally Posted by BASSMAN

Go with the glue down mounts from Renogy, you can buy them cheap on Amazon and no screws needed, I have 6, 100 watt panels on my roof and they have been there since 2017, as long as you get the right adhesive and the primer they will never come loose

Me too, Renogy glue mounts.
You can also add one screw in the two front mounts of each panel if it makes you feel better. That is, screws would add strength from coming off when driving down the highway at 60 mph.

Although I currently have 3 solid panels, I’m now a proponent of going with the flex panels for ease of install and limited weight.
Sure, they only last 10yrs in the sun (vs 25 years for solid panels), but who really cares.
If you still have this RV in 10 years, you can always replace.

[Ejohn2317]

The previous person made a very valid point that you have your attaching them to let's say a membrane roof or phylon roof you would probably be better off using something with a screw but if you have a fiberglass roof the renergy ones or I use the piece of aluminum channel which was not cheap for me worked fine.. if you do use the 3M industrial tape it's one and done so you don't mess up.

[Chateau_Nomad]

For those curious what your Thor TPO roof is composed of, here's a cross section. It's 5" of styrofoam sandwiched between 1/4" luan with various cross members for support. Lightweight, yet pretty strong for what it is.

I installed a couple MaxxAir fans, and took a pic of the fan hole. Of course there's metal supports for the fan, but you get the idea. The TPO is glued to the top luan, which is glued to the styrofoam. Then the ceiling luan is glued underneath... which has a textured vinyl glued to it.

Basically anything sufficiently glued to the TPO isn't going anywhere without taking the roof with it. My "glue of choice" is Eternabond tape... reinforced with "feel good" self tapping screws.