Solar Panel Install with Strut Channel Rails

[DaveTheWave]

I just recently bought a 2019 Thor Ace 27.2. I would like to install solar panels on the roof. However I'm very concerned about how to do this securely.

Short story: 2 questions. 1, does it make sense to screw down on the edge of the roof where the side walls meet the roof? I assume a regular wood screw would work in this case. 2, will the well nuts work for a rail in the middle of the roof, even though there is Styrofoam beneath the plywood?

I like the idea of mounting strut channels on the roof, then bolting the panels to the strut channel. This idea is from RV with Tito and Travel with Trails (YouTube links below). Since it's a TPO roof, I can't do attachment with VHB tape like Brian in the RV with Tito video, but I still like the ease of maintenance with strut channels.

One piece of advice I got from a service center was to mount one of the rails on the edge of the roof, where the wall meets the roof, so there is something solid to screw into. That seems sensible. I was thinking the other rail would be attached with 3 or 4 well nuts, but with the Styrofoam beneath the plywood, will it still work? I assume as long as I keep downward pressure on the nut as I tighten, the nut has to spread on the backside?

Thanks in advance everybody

 

[DaveTheWave]

Well, I lost all motivation to put regular solar panels on the roof of my RV. Returned the solar panels ans wend with thin and light flexible panels that I'll just tape down with Eternabond.

 

[Judge64]

I recently installed Starlink in my coach and when I drilled a hole in the roof to run the cable from the router to the dish, I almost fell over when I saw the wood underlayment on the roof is not plywood. It is some crappy paneling like they use on the walls that is so thin you can put your thumb through it easily. What really provides the backing strength is the very thick styrofoam under the paneling they use as insulation.

I opted for Renogy Flexible Panels for my coach. I used corrugated plastic sheets to act as a heat sink for the panels. I used elevator bolts to hold the solar panels to the corrugated sheets and then used EternaBond tape to secure the corrugated sheets to the roof. It has worked very well for me and gives me an easy way to remove the solar panels if I need to at some point.

I posted this in a thread on the Forum.

 

[DaveTheWave]

I recently installed Starlink in my coach and when I drilled a hole in the roof to run the cable from the router to the dish, I almost fell over when I saw the wood underlayment on the roof is not plywood. It is some crappy paneling like they use on the walls that is so thin you can put your thumb through it easily. What really provides the backing strength is the very thick styrofoam under the paneling they use as insulation.

I opted for Renogy Flexible Panels for my coach. I used corrugated plastic sheets to act as a heat sink for the panels. I used elevator bolts to hold the solar panels to the corrugated sheets and then used EternaBond tape to secure the corrugated sheets to the roof. It has worked very well for me and gives me an easy way to remove the solar panels if I need to at some point.

I posted this in a thread on the Forum.

Interesting. Is heat an issue with the flexible solar panels? I hadn't thought about that at all

 

[Judge64]

Interesting. Is heat an issue with the flexible solar panels? I hadn't thought about that at all

I had them taped right to the roof on my last coach and thay wasn’t an issue.

I wanted an easier way to remove them primarily but having the corrugated sheets as a heat barrier is a bonus.

 

[DaveTheWave]

I had them taped right to the roof on my last coach and thay wasn’t an issue.

I wanted an easier way to remove them primarily but having the corrugated sheets as a heat barrier is a bonus.

I see. I guess keeping them cool does maximize performance.

 

[DaveTheWave]

Bluetti AC300 and 2x B300 under the Sofa
I got the batteries installed under the sofa in my Ace 27.2. Fits great there

 

[Judge64]

Nice..... I went with BigBattery 170Ah LiFePO4 batteries. I have five of them installed.... three under one of the dinette bench seats and two under the other. I also have a central Vac installed under the first seat and a sub-panel under the second seat for the Inverter output plus I used it to rewire the coach so I could run any circuit off my 3000W inverter / charger.

 

[DaveTheWave]

Nice..... I went with BigBattery 170Ah LiFePO4 batteries. I have five of them installed.... three under one of the dinette bench seats and two under the other. I also have a central Vac installed under the first seat and a sub-panel under the second seat for the Inverter output plus I used it to rewire the coach so I could run any circuit off my 3000W inverter / charger.

Nice

 

[Chateau_Nomad]

A lot of overthinking this. Mounting kits with lightweight aluminum L brackets have been used for several years to mount standard solar panels. I currently have two 100 watt panels on my roof mounted that way... one has lasted two seasons, the other going on three. No issues whatsoever. Bracket feet and screws are covered with Eternabond tape and Dicor self leveling.

The only minor complaint is leaves/pine needles tend to collect underneath, so it takes a little attention spraying underneath them when cleaning the roof.

I've seen RVs with the roof nearly covered in panels mounted this way. I used the screws that came with the brackets... maybe I just got lucky and all 16 screws bit into something solid? :ermm:

 

[Judge64]

A lot of overthinking this. Mounting kits with lightweight aluminum L brackets have been used for several years to mount standard solar panels. I currently have two 100 watt panels on my roof mounted that way... one has lasted two seasons, the other going on three. No issues whatsoever. Bracket feet and screws are covered with Eternabond tape and Dicor self leveling.

The only minor complaint is leaves/pine needles tend to collect underneath, so it takes a little attention spraying underneath them when cleaning the roof.

I've seen RVs with the roof nearly covered in panels mounted this way. I used the screws that came with the brackets... maybe I just got lucky and all 16 screws bit into something solid? :ermm:

If you saw the thin paneling ised as Thor’s excuse for plywood under the TPO, it would scare the crap out of you! [emoji33]

You might have hit some studs along the way but this is one case when I would rather not be more lucky than good.

Other non-Thor coaches may have a better wood underlayment but after I saw the wood in my roof thetrnis no way I would trust anchoring anything substantial to it.

Besides all that the flexible panels are very lightweight and easy to mount. I’m also not going to be crawl around on the roof to angle them towards the sun as some people do.

 

[LarryD-THOR]

If you saw the thin paneling ised as Thor’s excuse for plywood under the TPO, it would scare the crap out of you! [emoji33]

You might have hit some studs along the way but this is one case when I would rather not be more lucky than good.

Other non-Thor coaches may have a better wood underlayment but after I saw the wood in my roof thetrnis no way I would trust anchoring anything substantial to it.

Besides all that the flexible panels are very lightweight and easy to mount. I’m also not going to be crawl around on the roof to angle them towards the sun as some people do.

Judge, why'd you stop at only 1 panel? I have the single 100watt panel which I know yours didnt come with, I wonder how difficult it is to splice in a few more. Can the wiring handle it etc...I'd love to throw 4 or 5 flex panels up there.

 

[Judge64]

Judge, why'd you stop at only 1 panel? I have the single 100watt panel which I know yours didnt come with, I wonder how difficult it is to splice in a few more. Can the wiring handle it etc...I'd love to throw 4 or 5 flex panels up there.

I have 3 panels installed. I first installed the two 160W flexible panels I had on my Outlaw. Then after switching to LiFePO4’s last year worh 850Ah, I added a 175W flexible panel.

There are room for more but i am trying to allow room if I need it to clean the A/C’s or do any repairs that may pop up in the future.

 

[LarryD-THOR]

I have 3 panels installed. I first installed the two 160W flexible panels I had on my Outlaw. Then after switching to LiFePO4’s last year worh 850Ah, I added a 175W flexible panel.

There are room for more but i am trying to allow room if I need it to clean the A/C’s or do any repairs that may pop up in the future.

didnt know that, so nearly 500 watt's, thats great! I was up on mine today replacing my failed back up camera and I took a look at the 100w. I'd love to swap that one out for a larger and then add a couple more. I dont know that gauge wire they ran and what it'll support. wondering if anyones done the same.

 

[Judge64]

didnt know that, so nearly 500 watt's, thats great! I was up on mine today replacing my failed back up camera and I took a look at the 100w. I'd love to swap that one out for a larger and then add a couple more. I dont know that gauge wire they ran and what it'll support. wondering if anyones done the same.

They run 10 gauge for the solar run. I originally installed my panels in parallel but I changed them to series. The current is relatively low in series and should be within the spec.