Attaching solar panels to my 2011 Rockwood Roo 21SS

[rojeck]

Hey gang:

I'd prefer not to drill holes in my roof. I have seen that some people go with either special adhesive or tape to attach their solar panels. Does anyone have any suggestions? Specifically, I will be attaching three tilt brackets for my 3-100 watt panels.

Dave

[wharfrat48]

For tilt brackets I think you would need to find studs and use screws sealed with Dicor and Eternabond. I would only trust adhesive or tape with flexible panels secured directly to the roof.

[hobienick]

The roof membrane is not bonded to the roof decking. Do not use adhesive. I ssf suggest avoiding flexible panels as well. Follow the advice above and screw into rafters.

[Underthedog]

I used well nuts from HD to secure 1 rigid Renology 100w panel with the z brackets also from Renology. I used 6 brackets. nuts secured with glue, then tightening bolt swells the nut. It does not meet your no hole requirement. Not sure I'd trust these with an adjustable mount though. It would seem like a lot of effort to climb up and down to adjust the tilt through the day, unless I misunderstand.

[chriscowles]

Originally Posted by rojeck

… I'd prefer not to drill holes in my roof. I have seen that some people go with either special adhesive or tape to attach their solar panels. Does anyone have any suggestions? …

I understand your hesitation but would be very skeptical about the ability for any adhesive to hold solar panels on a membrane roof securely. You result might be the roof material flapping in the breeze behind the trailer while you're driving at 60 MPH.

With Dicor and 1/4 lag screws directly into plywood, I think you needn't be as concerned about leaks as some people suggest. Yes, leaks are a horrible problem but they're avoidable. Even if you need to move the panel with the result being an unfilled hole, a small square of aluminum covered with Eternabond should be more than secure.

Originally Posted by Underthedog

I used well nuts from HD …

I used well nuts, too, but couldn't find a decent choice at Big Box. I ended up with these from McMaster-Carr. They are the antithesis of "I don't want to drill a hole in my roof." If you use well nuts, make sure they have a 1" long barrel. The first ones I used were too short and pulled out easily. (The description sounded right for the material thickness.)

In retrospect, I regret using well nuts as they're unnecessary and require bigger holes and more work. I learned that because I ran out of them when my plan required unanticipated revisions. I adapted by using 1" x 1/4" stainless lag bolts screwed directly into the plywood. That's what I could find at Big Box on short notice. I think they're actually more secure than the well nuts. Well nuts also make it hard to seal the underside of the bracket with Dicor because the nuts spin, making it hard to tighten them down.

Be aware that Rockwood trailers have NO studs in the roof. It's 1/4" luaun plywood laminated onto polystyrene foam. The only extra bracing is an aluminum frame supporting the A/C. There is, however, 1" square aluminum tubing around the edges. If mounting near the edge, self-drilling screws through the outboard brackets and into that frame make for a secure connection. I used #10 self-drilling stainless screws coated for aluminum. (Another gauge would work but I already had #10 washers.)

NB: McMaster-Carr is a good source for an exact type of fastener delivered on short notice but they're pricey, shipping is half the cost, and you have no choice about that.

[PhilFromMaine]

Originally Posted by chriscowles

...............

Be aware that Rockwood trailers have NO studs in the roof. It's 1/4" luaun plywood laminated onto polystyrene foam. The only extra bracing is an aluminum frame supporting the A/C.

I bought a new to me 2018 Freedom Express last Fall and I haven't been up on the roof yet. Can you generally tell from a visual inspection where your aluminum studs are on a generic trailer? The manufacturer says, from memory, that my roof is "walkable" although they did not supply a ladder. Is the latter statement a strong indication that the sub-roof is 3/4" plywood?

[chriscowles]

Originally Posted by PhilFromMaine

I bought a new to me 2018 Freedom Express last Fall and I haven't been up on the roof yet. Can you generally tell from a visual inspection where your aluminum studs are on a generic trailer? The manufacturer says, from memory, that my roof is "walkable" although they did not supply a ladder. Is the latter statement a strong indication that the sub-roof is 3/4" plywood?

My comments about studs and decking are limited to Rockwood trailers, which is what I and the OP have. (Note "Rockwood" in the subject.) I know for a fact they have 1" aluminum frames and no studs because the manufacturer uses that as part of their promotional information. I confirmed that in personal correspondence with factory reps.

Many manufacturers use different construction methods with a variety of materials, with and without joists. I have no knowledge about Freedom Express trailers but I seriously doubt the roof deck is 3/4" plywood. I've never heard of even floors being that thick. Some roofs are only 3/16" Luaun, the same stuff they use for interior wall paneling. It's little more than a veneer.

[rojeck]

Hello again:

Thanks for the advice. I will be drilling the holes in the roof, according to your suggestions. Now, I need to figure out a wiring plan. I saw one guy wire from the panels to the converter:

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

. Others I believe go straight to the battery. I really want to get this right the first time. It would be nice to see a customized plan for the Rockwood Roo. Does anyone have suggestions?

[Larry-NC]

Originally Posted by hobienick

The roof membrane is not bonded to the roof decking. Do not use adhesive. I ssf suggest avoiding flexible panels as well. Follow the advice above and screw into rafters.

That's very unusual. Roof membranes are usually bonded to the roof decking with contact cement. If they weren't (or if the bond fails) the membrane will form a huge bubble at highway speed due to the vacuum formed--similar to lift on an airplane wing.

That said, I've peeled membrane back. It takes some strength, but not that much.

[rsdata]

Does anyone have any suggestions? Specifically, I will be attaching three tilt brackets for my 3-100 watt panels.

Would you not rather have your panels mobile? If camping under trees ( preferable)? Maybe one permanently mounted for when you are driving...

[mnoland30]

I had the same fear. I glued my flexible 100 watt panel to the roof with silicone caulking. I did that on my last camper and could not remove it when I sold the camper. Because they are plastic and not glass, the sun degrades the panel in a few years. If I had it to do over again, I believe I would do what is suggested above. Drill the holes to mount your panels and seal them with dicor or silicone caulk. Mounting a flat panel lessens it output, but here in the southwest, that hasn't been a huge problem for us. I did buy a portable 100 watt panel and made an extension cord for it so I could aim it at the sun. We don't carry a generator anymore. I also replaced the marine batteries with two 6v golf cart batteries from Costco (wired in series). They are true deep cycle and much better than the hybrid marine batteries. I love the roof panel because it keeps the batteries charged while in storage.

[Matthuck88]

I would be leary of screwing things to the roof on these campers. As stated above, the only rafters are in front and behind the ac unit and the rest of the roof is 3/16” plywood. I rebuilt my roof last year, it required a bit of ingenuity to do it due to no framing support in it. I would not want to trust a lag into thin plywood at highway speed. I would consider thru bolting it if I could find a way to conceal the washers and nuts.

[Larry-NC]

Originally Posted by Matthuck88

I would be leary of screwing things to the roof on these campers. As stated above, the only rafters are in front and behind the ac unit and the rest of the roof is 3/16” plywood. I rebuilt my roof last year, it required a bit of ingenuity to do it due to no framing support in it. I would not want to trust a lag into thin plywood at highway speed. I would consider thru bolting it if I could find a way to conceal the washers and nuts.

Well, you'd be going through the roof, not the interior ceiling, right? That means you could use toggle bolts or Molly bolts through the roof deck and they would not be visible from the interior.

[chriscowles]

Originally Posted by Matthuck88

… As stated above, the only rafters are in front and behind the ac unit and the rest of the roof is 3/16” plywood. …

Plywood used on a Rockwood roof is 1/4". Not a lot when thought of in terms of 16ths of an inch, but it's 33% thicker than 3/16" plywood.

Many people screw things directly to it without failures. An adequate number and size of screws is required.

[lablover]

We bought a solar suitcase so we can move it around to follow the sun

[mrcotton73]

I recently installed 4 100w solar panels on my 2013 Shamrock 21ss. I installed two sets of aluminum strut channel (very light weight) - vhb tape on tune underside of the channel and screwed into the roof well using 1 1/4" S.S. lag bolts (5mm). All holes covered with lots of sealant. Made custom brackets (just 3/16" aluminum plates bolted to the solar panels using 1/4-20 bolts and bolted to the struts using cone nuts). This way I can remove / replace panels in the future without having to remove the strut channel.

Two panels are connected in series each and connected to the other set in parallel using "Y" mc4 connectors. The final wires from the Y-connectors are bright down the side of the awning arm (which also contains the power cord for the awning and use the same hole to bring them into the camper - just next to the front storage compartment door).

Pics attached.