Drilling holes in trailer roof to install solar: worth it?

[OregonMan]

Hi guys, so for a while now I've been wanting to install solar on my travel trailer. Problem is I'm not very handy, a little on the heavy side and drilling holes through my trailer roof just doesn't sound great.

Do you think it's possible to get the same amount of power generated from solar using the flexible foldout panels? Would it be possible to just use these during the day as we need them, then stow them away, without having to install a bunch of panels on the roof?

I feel like solar tech is improving quickly. Don't want to screw up my trailer and spend a full day working on this if in 2 years Tesla comes out with some amazing portable solar generator. Thanks for any feedback.

[Tom_M1]

Here's my solution. The panels can tilted up in place or removed and set out in the sun using extension cables:

[StirCrazy]

I had no issues drilling to mount the pannels, especialy when you do it yourself as you know how good you sealed it up. I put a little bit of Geocell to fill the hole and forced some between the substrate and the roof membrane then I put a good bead of it between the roof membrane and the solar mount. then after it was all mounted I did a good hit of dicore over and around the foot. nothing is getting in that hole.

Steve

[ktmrfs]

travisc wrote:
check out amsolar.com in Eugene they did our install 10 years ago, and friends are going down in a few weeks to have another install there.

even if you do the install yourself, amsolar is a great source of parts for a great solar install.

[travisc]

check out amsolar.com in Eugene they did our install 10 years ago, and friends are going down in a few weeks to have another install there.

[dave17352]

Putting a couple screws in your roof is no big deal. Think about it all you have to do is waterproof the area of a couple screw heads. Fill the hole with caulk screw in and as others have said a little dicor on top for frosting! Piece of cake!

[ktmrfs]

Ed_Gee wrote:
One consideration - portable solar panels can 'disappear' sometimes if you're not around..... not to mention the hassle of setting up or putting away everytime you come and go. 3M VHS tape is proven to be a good way to mount solar panels on roof. However, if you're not physically or skillfully up to it then maybe you should either use portable panels or drive over to Springfield Oregon and visit AM Solar.

yes, portables can be a hassle, and can disappear, but also let you park in the shade, and tilt the panels for optimal output. But then roof mounted ones will charge while your driving down the road.

I have three 160W on the roof and three 200W portables. I Dig out the portables if needed, otherwise I rely on the roof.

[pianotuna]

Hi,

Fixed solar charges when RV is in storage. Portable doesn't.

Dicor is your friend.

[time2roll]

Your roof is already full of holes. Do you think the RV manufacturer makes any effort to have fewer holes?

Drill and Dicor and get the solar working for you.

[rlw999]

agesilaus wrote:
Some folks are using super strong 3M tape and say it works as well as screws

That would depend on the type of roof, tape may hold on a solid fiberglass roof, but if you have a rubber roof membrane, you may find that your solar panels ripped off half your roof membrane when they were blown off after driving on the freeway. Even if the membrane is glued down that glue isn't meant to be structural.

[Lwiddis]

Taping is a proven method of attaching solar panels to an RV but not those with a rubber roof, OP. My panels and routing of the wire to the controller required 13 holes...no leaks!

Yes, portable panels can be better aimed at the sun...or you can just buy another panel for the roof.

[Ed_Gee]

One consideration - portable solar panels can 'disappear' sometimes if you're not around..... not to mention the hassle of setting up or putting away everytime you come and go. 3M VHS tape is proven to be a good way to mount solar panels on roof. However, if you're not physically or skillfully up to it then maybe you should either use portable panels or drive over to Springfield Oregon and visit AM Solar.

[SpeakEasy]

Look at it this way concerning the holes in the roof: If you drill a hole that is narrower in diameter than the screw you're using, the hole will be completely filled with the screw. I've been putting screws into boat decks for most of my life for one reason or another. You drill the right-sized hole, fill it with appropriate caulk or sealant, drive the screw in, cover it with sealant, and you're good to go. On a trailer roof, the last step is Dicor self-leveling sealant. I did my solar panel on my trailer roof that way. (On two of the four brackets I made sure to drill into a framing member of the roof. The other two brackets there was no framing member where I needed to be.)

Make sure you know the way your roof is constructed so that you don't go deeper than you should and so that you don't use screws longer than you should. If you can't be 100% certain of this part, then don't do it.

There is no way I'd be willing to drive down the highway at 65MPH with a solar panel attached to my roof without screws.

Concerning the portable ones - If you're anything like me you will hate the inconvenience of having to set them up all the time. With a roof-mounted panel they are up there working for you all the time without you having to even think about it.

-Speak

[ktmrfs]

OregonMan wrote:
Hi guys, so for a while now I've been wanting to install solar on my travel trailer. Problem is I'm not very handy, a little on the heavy side and drilling holes through my trailer roof just doesn't sound great.

Do you think it's possible to get the same amount of power generated from solar using the flexible foldout panels? Would it be possible to just use these during the day as we need them, then stow them away, without having to install a bunch of panels on the roof?

I feel like solar tech is improving quickly. Don't want to screw up my trailer and spend a full day working on this if in 2 years Tesla comes out with some amazing portable solar generator. Thanks for any feedback.

Second question first. In reality portable panels tilted to reasonably align with the sun will outperform flat panels on the roof by a noticeable margin. I have 3 160W panels on the roof and 3 200W portable panels. Even Two of the Portables always outperform the roof.

Now flexible panels that can't be tilted, laying flat on the ground are likely to give the same performance as fixed roof panels.

Downside it portables need to be stored, don't work when driving down the road, take time to set up, and can grow legs.

Upside is you can park in the shade and put the panels in the sun. Roof panels mean parking in sun.

Now for the roof question. I used brackets to attach the panels to the roof. brackets are screwed into the roof. for installation I drilled for the screws, then put dicor in the screw holes, placed the brackets on top, screwed them in and then covered the base of the bracket and screw head with dicor. basically how other roof items are attached. Then ran the cable down through the fridge vents, attaching the cable to the roof with cable clamps using VHB to the roof.

[Lwiddis]

Sure, the foldout panels will produce the same amount of power. Early morning, set up panels, move as necessary for sun. Take panels in for trip to town for lunch to prevent theft. Return from town, set up panels a second time, move as necessary for sun. Late afternoon, put panels away for a second time that day. Not fun. My roof panels were working earlier than your’s and later than your’s with no effort.

[TurnThePage]

I mounted panels to my plywood roof with screws over 15 years ago. No leaks ever. I'm not all that handy either. I ensured that I was hitting the cross members and not just the thin plywood. I squeezed a little caulk in each hole before screwing into it and left a layer of caulk between the brackets and the roof, and then used good self leveling caulk over the top of the whole thing.