Upgrade advice for flat roof solar

ilikesleeves · 20-11-2025 11:30AM #1

Last year we renovated in Cork City and had the one-stop-shop treatment, including solar and battery install.

I'm disappointed with the low number of panels for the flat roof (aspect is east/south) and want to fit more in to boost production. Five panels on the pitched roof at the front, west facing.

What would you recommend? Panels are jinco and the existing mount system is K2 I believe. I want to raise the setup to try minimise shading from the roof ledge, considering could portrait mounting be better - or just keep it simple and accept that best case is fitting two more at the back?

bullit_dodger · 20-11-2025 07:38PM

Couple of things to be aware of if you haven't already thought of them.

The panels closer to sun will tend to shade the panels behind them, esp in the winter months where the sun is lower.
The panels will catch the wind if exposed.
You'll ideally need 15 deg or higher to get the rainwater off the panels. Flat panels (i.e. ones less than 10deg slope) tend to accumulated dirt/grim on the over time. This can of course be physically cleaned off with a bit of water, but if the slope is 15 or higher, usually rain will do the job for you.

You can mitigate some of the #2 issue if you create a baffle on the vertical (like what they have in your photo)

If if was me, I'd see if you could fit two more on the back (probably by sliding the existing two forward a little), and then see if you can fit another on in there in portrait nearest the camera view point. You might even be able to get two in portait bringing you to 8?

ted1 · 22-11-2025 11:54PM

gave you any panels on the main roof ?

ilikesleeves · 25-11-2025 11:46AM

https://www.boards.ie/discussion/comment/124010911#Comment_124010911

None on the pitch roof at the rear - see the roof setup - 5 on the west facing pitch at the front of the house

ilikesleeves · 25-11-2025 11:48AM

https://www.boards.ie/discussion/comment/124004424#Comment_124004424

Thanks for the feedback - your last comment is probably where I will land, might start with adding two panels at the rear and see if I can manoeuvre things around to mitigate shading between panels and from the roof ledge.

perryboy · 25-11-2025 11:44PM

I had a similar setup with a flat roof. I slightly raised the tilt and added two more panels on the south side. The difference is noticeable, especially in winter when the sun is lower.

...Ghost... · 28-11-2025 09:39PM

If you raise the rear panels higher, like tired seating, you could bring them closer to the front ones and may be able to fit a third row on a higher tier. Changing orientation could allow even more panels depending on available space.

Upgrade advice for flat roof solar

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