Solar panel install

[terryaGJ]

I'm getting ready to install a couple of Renogy solar panels on my EPDM covered 3/8" plywood roof. Because of space required, I have to place them near the front where the wind force will be highest. Their website recommends well nuts (expansion nuts) for use on RV roofs rather than the self tapping screws they actually provide with their mounting brackets. Has anybody used well nuts to attach brackets to the roof? I'm going to use six brackets per panel rather than the usual four, but am still nervous about how well they'll hold. Any suggestions would be appreciated.

[bdb2047]

I mounted 3 panels on front roof.I set panels in place marked location of attachments,drilled pilot holes,1 for each bracket drill running in reverse.Used Dicor under attachments and in holes, 1"x#12 SS screws to attach to roof Dicor to seal around everything.Been across country 2 times no issues as of now.

[terryaGJ]

westend wrote:

terryaGJ wrote:
I might have to rethink this.

An alternative might be to mount them on the sides. There is a member on the Forums, Tom from New Hope, that his modules on the sides. He has a hinge apparatus that allows the modules to be flat or at any angle. A strut is used to prop them up, IIRC. The hinge pins are removable so they can be deployed onto the ground, if necessary.

If it was me and I couldn't find the roof truss under the plywood (I can and did), I'd use a molly bolt just slightly smaller than the bracket hole and through drill the roof, insert bolt, tighten, and they are fastened. Cover the bracket with your sealant of choice.

FWIW, I installed my mounting brackets through a layer of Eternabond tape. This 45 second Video at Eternabond convinced me.

Although could be viable, I think way beyond my capabilities. I'm going to attach my panels today. I laid them out on the roof yesterday after having to modify the Z mounts to make some of them vertically adjustable, and adjustable to fit the roof curves. Instead of using four, I'll go with six mounts. I'll lay down some Eternabond tape down first, then use self tapping screws on some mounts, well nuts on others, then cover with lap seal. Decided not to use the 3M VHB tape in case I need to remove panels at some point.

[terryaGJ]

"I have a solar panel, and will add a second. My question is, why attach to the roof? Are you always going to have the camper in the sun?
I set my panel out usually next to the road, where I'll get the most sun, and move it around as needed. Yeah, more work, but I can camp in the shade and find a spot for the panel/charge controller/battery. I always have one battery on the pup, a second one being charged by the panel and off the pup."

I thought about doing it this way but we move around a bit and don't want to deal with tearing down and storing panels (we're space limited). Also want to be charging when traveling. It certaining would be nice for maximizing your solar harvest though.

[westend]

terryaGJ wrote:
I might have to rethink this.

An alternative might be to mount them on the sides. There is a member on the Forums, Tom from New Hope, that his modules on the sides. He has a hinge apparatus that allows the modules to be flat or at any angle. A strut is used to prop them up, IIRC. The hinge pins are removable so they can be deployed onto the ground, if necessary.

If it was me and I couldn't find the roof truss under the plywood (I can and did), I'd use a molly bolt just slightly smaller than the bracket hole and through drill the roof, insert bolt, tighten, and they are fastened. Cover the bracket with your sealant of choice.

FWIW, I installed my mounting brackets through a layer of Eternabond tape. This 45 second Video at Eternabond convinced me.

[retiredtravele1]

I have a solar panel, and will add a second. My question is, why attach to the roof? Are you always going to have the camper in the sun?
I set my panel out usually next to the road, where I'll get the most sun, and move it around as needed. Yeah, more work, but I can camp in the shade and find a spot for the panel/charge controller/battery. I always have one battery on the pup, a second one being charged by the panel and off the pup.

[terryaGJ]

I might have to rethink this.

[westend]

If you use the well nuts, I'd suggest to epoxy them in place. I haven't had very good luck with well nuts and plywood.

[terryaGJ]

Thanks for the advise and pictures guys. I think I'll use both the well nuts and VHB tape to attach the mounts.

[n3eqf]

I just installed a 100W Renogy panel on my RV roof and used well nuts. I'd never used this type of fastener before, but they are great! Once you tighten them down, they expand and seal inside the holes. I don't think they'll ever come out.

[Golden_HVAC]

I only used rubber roof sealant on my mounts, and they have been up there since 2000, without any problems.

I cut 6" long 2" angle aluminum from Home Depot, and made 4 brackets. My solar panels are about 6" behind the front roof cap, and yes I can hear them inside. I have always been thinking about putting some rubber on the leading edge, to prevent air from getting under the panels while driving.

It is nice that I have 1" of air under all my solar panels. My front pair are 120 watts each, so pretty large.

At least the price has dropped a lot since I bought my 120 watt in 1999 at $429 each. Now you can get 140 watt for $229!

Here are pictures of my roof being recoated, with the solar panels in the pictures.

Golden_HVAC wrote:

rickthescot wrote:
Sounds like a great idea. I guess asking for pictures again is not going to persuade you though. We are visual creatures and I don't think 1000 words will accomplish what one image will. You can do it, just one pic.

More pictures that I took a few days ago to post pictures of my solar panels, and their mounts. Some pictures are really close up pictures of the solar panel mounts, and give a clear picture of howrough the surface is.

Golden_HVAC wrote:
Hi,

This is my front pair of panels. 120 watt mounted on a curved roof, 102" wide.



This is the mount it is held on with three rivets into the frame, and then the bottom half is 6" long aluminum, with nutsert in the upper piece, bolt you can not see from the outside edge pointing inward.









This picture shows the bigfoot panel mount sold by RvSolarElectric for $35 a set back in 1994. I wonder what they cost today?


This picture shows the panels tilted while I was working on the roof.

Fred.

Good luck,

Fred.

[westend]

Either use molly anchors through the plywood or use longer stainless steel screws into the roof trusses. The VHB tape is also very good but that will only anchor to the roof membrane. Added insurance with the tape but I would use a fastener also.

[pianotuna]

I'd add VHB tape (a 3M product) under the mounts