diy solar

diy solar

Spacing between panel rows

Tulex

Solar Addict
Joined
Mar 30, 2023
Messages
837
Location
Western NY
Putting up 3 separate panel batches on 3 different roofs, each will have 2 rows of 7. Using Unirac system. The clamps to mount the panels are U shaped, one inch wide with about a 3/16" lip on each side.
Unirac-Mid-Clamp-302030M_300x.jpg

So, side to side spacing is fixed to the clamp. I assume expansion isn't an issue, as the rails will expand just the same.
But, when searching for how much gap to leave between rows, there are multiple sites that say 4-7 inches for expansion. That makes no sense, at least not for expansion, as nothing expands that much, and most images of installs have nowhere near that much space.

So, what is the minimum gap I should have between rows? Being in NY, snow is an issue. My thought is that the larger the gap, the more room for snow to gather/get a foot hold. Maybe that isn't the issue I think it will be?
 
I used two 3/8 inch bolts for row spacers. When the upper row was clamped down, I removed the spacer bolts
 
Do you want to be able to walk between the rows to do maintenance?
I have kind of a unique roof. Porch with a shallow roof right at the bottom of the panels, so will be easy to work on the bottom row, and the back of the roof also has a shallow pitch, the panels will be near the peak, so also easy to work on the top row.
 
What mounts are you using for your roof? Have my panels, but haven't figured out how or what system I want to mount them with yet.
 
What mounts are you using for your roof? Have my panels, but haven't figured out how or what system I want to mount them with yet.
I went with all Unirac mounts are Unirac Flashloc. In fact, installing them right now, It is hot up on the roof....... So far, very easy to install. I found them on Ebay, seller had 9 boxes of 20 at the time, just checked, unfortunately, he is sold out. I went with the regular racking, not the light. Got the rails (and wire while at it) at City Electric Supply, by far the cheapest I could find for the rails, and no shipping fee, which was a killer from other places. If you do go with the Unirac Flashloc, they do come with the bolts to mount the rails. Got the rest of the hardware at RES Supply, again, no shipping.

Oh, and if you do with either Unirac or Ironridge, they both have config sites to build your parts list. Matched to your panels and conditions.
 
Last edited:
I went with all Unirac mounts are Unirac Flashloc. In fact, installing them right now, It is hot up on the roof....... So far, very easy to install. I found them on Ebay, seller had 9 boxes of 20 at the time, just checked, unfortunately, he is sold out. I went with the regular racking, not the light. Got the rails (and wire while at it) at City Electric Supply, by far the cheapest I could find for the rails, and no shipping fee, which was a killer from other places. If you do go with the Unirac Flashloc, they do come with the bolts to mount the rails. Got the rest of the hardware at RES Supply, again, no shipping.

Oh, and if you do with either Unirac or Ironridge, they both have config sites to build your parts list. Matched to your panels and conditions.

What was your total racking cost? Looking at Unirac now.
 
What was your total racking cost? Looking at Unirac now.
Flashloc mounts $300 Got lucky finding these, would have been over $600
Mid clamps, end clamps, and ground lugs $328
Rails and bonding splice bars $1222. Ended up buying 24 14 footers, was still cheaper than buying shorter ones that would have worked.

So, $1850, which I don't think is bad, considering this will do 3 sets of 14 panels.

Don't forget to buy wire clips if you want to keep you wires off the roof. I made my own, would have been much easier to buy them.
 
Flashloc mounts $300 Got lucky finding these, would have been over $600
Mid clamps, end clamps, and ground lugs $328
Rails and bonding splice bars $1222. Ended up buying 24 14 footers, was still cheaper than buying shorter ones that would have worked.

So, $1850, which I don't think is bad, considering this will do 3 sets of 14 panels.

Don't forget to buy wire clips if you want to keep you wires off the roof. I made my own, would have been much easier to buy them.
Thanks for the tips. My first round will be 10, 250w panels. So, not nearly as much needed as you there. I have to make a decision this week. We’re the roof mounts easy to install? I have a new roof, architectural shingles. Worried about the install there.
 
Thanks for the tips. My first round will be 10, 250w panels. So, not nearly as much needed as you there. I have to make a decision this week. We’re the roof mounts easy to install? I have a new roof, architectural shingles. Worried about the install there.
Very easy to install. Snap a line, find the rafter. I was able to find the rafters just by tapping the roof, listening for the solid sound. Put in 20, only missed 2 times, and that isn't a problem because the mount covered up the bad hole. Simple as legging it down and filling with provided sealant. If it lands on an uneven shingle, like where it's doubled, you can just cut that part of the shingle off where the mount sits. They say you can have one layer difference but not 2. I didn't like any uneven, so I trimmed a few shingles. Map it all out first, because you don't want to land on the overlap of rows. Most likely you can shift it, because the panels have multiple mounting holes that you won't be using, so if you are in the general area, you will be fine. If you use the end clamps, they are awesome. Just slide it all the way in, rail should be even with the end of the rail, and tighten it up. The unit will slide to the panel, then clamp down. There are youtube videos of all the install parts.
 
Back
Top