Flashing detail for combiner box on a standing seam metal roof

[texassun888]

Hello there. Long-time reader here! I have an 18 panel 2-string 4.5 kW solar array on my asphalt shingle roof. As you can see from the picture, the combiner box is properly flashed for this roof type. I will be replacing my roof soon with a standing seam metal roof (24 gauge, kynar coated, 16 in wide panels with 1.5 in seam height). My roofing contractor does not know much about solar panel installation, thus I will be removing and re-installing the panels myself. I've narrowed down the proper S-5 clamps to attach the racking to the metal roof. That part is clear to me now.

I need to figure out how to replace the combiner box on a standing seam metal roof. How would the flashing be done in this case? Anyone familiar with the proper details?
Many thanks!

[emartin00]

I believe you will have to switch out the box to something rail mounted, and then run the conduit through a standard pipe boot made for metal roofing.
I'm not aware of any boxes made to mount directly to a metal roof.

[solarix]

ditto.

[texassun888]

Thanks for your tips. I wonder if in this case - going with a traditional metal roof boot, it would be better to bring the wires through the roof and then combine them in a box mounted to the underside of the roof?

I also found this video, using a standard flashed box installed with the half sheet technique. What do you think about this? I haven't discussed yet with my metal roof installer if they're willing to do it this way.

https://www.youtube.com/watch?v=0czDmL5mBSE

[bob-n]

I'm not qualified to judge, but to my eye, the video's method looks like a great approach. As long as the roofing material supports overlapping like that, it could be even better than a standard pipe rubber boot.

Before doing it, I would check whether Soladeck approves/supports this installation method. You want support in case something does go wrong.