[Arthur2020]

affixing solar panel brackets to motor home roof , can they be glued on with say Simpsons 170 -3 with out screws or do they require screws and if so is their a particular type of screw . Existing roof difficult to detect framing underneath . Any advice appreciated. Arthur

[Mark]

Hi Arthur
I have fixed a 315watt panel to my fibreglass roof just using the Simpson ISR 70-03 adhesive.
I used a set of 6 ABS blocks and two aluminium angle brackets half-way down each of the long edges.
Some ABS blocks have a greater glueable area than others.
Need to prepare both surfaces carefully.

I've also used the same adhesive to fix a pair of kayak racks to the roof as well.

[scubadoo]

Arthur

Two of our solar panels have survived 6 years of fulltime travel attached solely with Sikaflex 11 FC adhesive/sealant to our fibreglass roof.
Last check this morning while cleaning the panels. They are not parting company anytime soon.

A few previous posts of mine.
https://nzmotorhome.co.nz/Forum/viewtop ... 53#p134853
https://nzmotorhome.co.nz/Forum/viewtop ... 273#p97273
https://nzmotorhome.co.nz/Forum/viewtop ... 47#p110247
https://nzmotorhome.co.nz/Forum/viewtop ... 46#p100146

The third panel was attached about 3 years ago with Selleys ArmourFlex adhesive/sealant as a test and comparison. Perfect so far.

[mattn]

Another one on here... https://nzmotorhome.co.nz/forum/viewtop ... 0&p=161759

One posts made a prediction, that unfortunately came true in Australia. https://www.thegreynomads.com.au/solar/
And its not the only time panels have come loose... https://www.caravanersforum.com/viewtopic.php?t=31446

Use the right stuff - Sikaflex 252, not the cheaper versions that are not as strong. Do it properly, proper prep work using Sika cleaners and follow instructions to the letter. The correct stuff is not cheap to buy, and there are cheaper products that appear to do the same job, but they are a lot cheaper buy than doing it a second time, defending a ticket for unsafe loading or worst case, a manslaughter charge.

[scubadoo]

I am guessing that we have no idea how either of those panels were attached and the preparation or lack of involved
Screwed and glued panels have come to grief as well.
I'm also guessing that our gelcoat will detach from the fibre-reinforced substrate long before the adhesive/sealant decides to separate.

252 will not be going on our roof. Without near perfect cleaning and priming of all carefully selected surfaces it will not perform as well as 11 FC for our use.
Achieve that much stronger perfect attachment and replacing a panel later could prove interesting.

[mattn]

No one is certain of anything around the materials and prep work done, too soon for the coroners report in the accident that killed 3 people. However I stand by my staementy about doing the prep work right and not skimping by using cheap products.

As far as the argument around 11FC or 252 - I was only going off the manufacturer recommendations and have no expertise to dispute your assertion 11FC is better for the task.

https://www.caravanersforum.com/viewtopic.php?t=55989

[scubadoo]

I totally agree Matt. Preparation is the key. I have seen some atrocious workmanship and not just from amateurs.
Sikaflex 11 FC is not cheap.

https://nzmotorhome.co.nz/forum/viewtop ... 32#p161632
I will be replacing the other hatch next fine spell. I do not expect to find any more than 20 cents worth of sealant applied in this one either.

[Arthur2020]

many thanks Guys , Arthur