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What Unistrut Rail to use to mount panels on roof of an bus/RV?

TedH

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I am visiting a local unistrut dealer in Tampa area and will be sourcing two rails and associated hardware to mount 4-6, 250wall panels on the roof of my 1989 MCI 102AW3 (converted) bus. I plan to attach two rails running the length of the bus between the two top hatches; approximately 20-30' total length. Granted, I may have to pick the rails up with my bus as my pickup truck may be too short.

What type of rail and hardware are recommended for an RV roof mounted Unistrut assembly to attach solar panels?

The panels will be mounted flat and across the width of the bus (they will be mounted widthwise, not lengthwise on the bus). I will be running the cable into the bus near my refrigerator/power wall that is inside the bus.
 
I've been doing just this.

I decided to use the short - 1" deep superstrut from lowes (hd has the same).
The struts are mounted to my roof with lag bolts which are sealed with self leveling lap sealant.

I use a pair of struts for three panels.
Each panel has a pair of brackets that are side mounted to allow the panel to be tilted upward.
Each panel has a pair of brackets along one side that bolt directly down.

For tilt brackets, I used 3/8 hardware going through a 3/8 to 1/2 bushing.
For lock down brackets, I just used 1/2 inch bolts for both unistrut bolting and bracket to panel mounts.

Drilling is easy, I use a bracket as a drilling guide, with one of the bushings to center a 3/8 bit to mark the drill point.
Then I used a pilot bit to drill the hole and then widen to the 3/8 or 1/2 size.

For my setup, I like the tilt system. I can unbolt the lock downs and tilt panels up for access to wiring.
The tilt system is a milt pain to install - mostly because I'm sharing L brackets between panels along the tilt side.
 
I used the deep hot dipped galvanized, but cut it up as I'd need to have bought the 6m lengths to accommodate the 3 solar panels, whereas cutting it let me do all panels with 1 x 3m length. I then used the shallow channel bolted to each panel to raise them up enough to get access to underneath to secure them, and also allow me to still open my sunroof. Mine are purely glued on with a Soudal product, if done correctly, ie remove all paint and glue direct metal to metal then you can consider the strength the same as welding the unistrut to the roof.

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I'm going with Grainger aluminum, 1-5/8" x 1-5/8", 10ft. And stainless hardware/ spring nuts/ bolts 1/4-20
 

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I'm going with Grainger aluminum, 1-5/8" x 1-5/8", 10ft. And stainless hardware/ spring nuts/ bolts 1/4-20

Check out Zoro. I purchased qnty 8 10ft aluminum 13/16th height for around $200. They come in batches of 4. Really great quality and arrived in 2 days. Very pleasantly surprised.
 
I did almost 160 feet of regular P1000 galvanized strut on mine. You can see the link to my build thread in my sig.
 
I did almost 160 feet of regular P1000 galvanized strut on mine. You can see the link to my build thread in my sig.

Your install is what convinced me to go strut channel versus z brackets on this current install.
 
I checked out Zoro. Unfortunately, I can't buy qty 4 of 10' aluminum, which is what I need if I adopt the strut approach. Minimum purchase is qty 8.
 
No idea, but pretty light. All 8 cellophane wrapped I could cary on my own without issues. Maybe 100 lbs for the 8?

Hmm... I looked at regular slot because it was cheaper but I had to buy 8, making the total purchase more costly and wasteful. The long slotted type costs more but is sold individually. I'll reconsider.
 
For a van, which is more or less a short bus, I used 8020 Al L brackets to fasten to the roof mounts.

EPDM from mcmaster for pads in between the L bracket and the van.

Then ran 1515 rail the length of it. Attached the panels to the 1515.

It isn't the cheapest method but it helps lift the panels high enough up so that they will clear the crown of the roof. Also provides for things being out of alignment.
 
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