how to mount some solar panels on a corrugated roof?

[julianf]

I assumed there would be an off the shelf fixing for this job, but now im not so sure!

I have a number of these -

https://www.solartradesales.co.uk/Cache ... BMC-39.pdf

The 355w panels, IIRC (they're in my friends barn at present). Datasheet says they're 35mm thick and 21kg in weight.

And id like to mount them on this type of roof -


Trapezoidal box section or something?

The pitch of the roof is minimal. 12.5 degrees ish. OSB and purlins under the metal.


All the fixings ive seen sit on top of the ridges of the roof, which seems not so good?


Im currently wondering about using 4040 (40mm x 40mm) t-slot extrusion running up the gullies, fixing through the roof to the purlins, and then some horizontal mounting rails off this. But the extrusion etc is looking like more than i paid for the panels!


Or...

I could get extrusions just over the length of the panels (ie a bit more than 2m, which is also not cheap) and just mount the panels on the top and bottom edge.

I still think there must be a better way than either of these though. Hence wanting to use your brain also!

Thank you

 

[Edward Teach]

Option 1
Horizontal,
Then vertical fitted, to suit your panels.

edit: The roof sheets are plenty strong enough,
There is no need to fit to the purlins.

 

[mike os]

Unistrut?

Needs fixing into purlins not the sheets so will be a pita

 

[morssdn]

When I mounted a small panel on a corrugated roof I screwed the Ali frame to two wooden battens which sat in the roof valleys, which were then bolted through with nuts on underside.
The panel was about 800 x 500 and the battens spaced accordingly.

 

[gaz1]

 

[fizzy]

Just leave them in the barn

 

[Gareth J]

I used renusol metasole brackets and clamps;

https://www.renusol.com/files/content/Produkte/MS%2B/Var-MS_P.png

They span a few ridges and are holding the panels on a steep roof nicely. Less aluminium to buy than full length bars but a bit of thought when laying out needed

 

[Gareth J]

 

[minimutly]

The cowboys that did my daughters used purlin brackets that screw through the roof into the wooden purlins, with a gob of silicon (ct10 they called it) and flat washer to seal. Problem was the “purlins” were 3 by 1.5 pre made trusses....
Effin’ cowboys...

 

[julianf]

View attachment 313880

Thank you. If theyre good for the job, which i assume they must be, they look like my simplest option.

I think these are the bars -

Renusol 420420 MS+ Portrait Rail Set 0.4-1.33mm

<p>Renusol are a leading manufacturer of solar panels worldwide and are led by the motto ‘Solid, Simple Service’. Renusol’s commitment to developing versatile, innovative products have led them to worldwide success, offering unique, easy-to-install products to suit a wide range of applications...

www.tradesparky.com

and these are the mid and end clips -

Renusol 420082 Mid Clamp (G)

<p>Renusol are a leading manufacturer of solar panels worldwide and are led by the motto ‘Solid, Simple Service’. Renusol’s commitment to developing versatile, innovative products have led them to worldwide success, offering unique, easy-to-install products to suit a wide range of applications...

www.tradesparky.com

Renusol 420081 End Clamp (G) Silver

<p>Renusol are a leading manufacturer of solar panels worldwide and are led by the motto ‘Solid, Simple Service’. Renusol’s commitment to developing versatile, innovative products have led them to worldwide success, offering unique, easy-to-install products to suit a wide range of applications...

www.tradesparky.com

installation guide seems to confirm the numbers -

https://www.renusol.com/files/content/Downloads/Installationsanleitungen/20210608_AllLanguages_MS%2B_P_InstallationGuide.pdf

I initially got these bookmarked -

Renusol 420402 Metsole+ Roof Adaptor 0.5-1.5mm

<p>Renusol are a leading manufacturer of solar panels worldwide and are led by the motto ‘Solid, Simple Service’. Renusol’s commitment to developing versatile, innovative products have led them to worldwide success, offering unique, easy-to-install products to suit a wide range of applications...

www.tradesparky.com

but i cant work out what they actually are. The install guide certainly has 420420.

 

[frank horton]

have to do the same on my barn next spring.....but solar water panels with a 250 ltr tank as well....
so it all depends on how thick the steel is....mines very thin and 40mm insulated...
mine will get a hard wood frame sitting in the valleys of the roof panels, to spead the load out....
then make the frames fit the wood.....

 

[Gareth J]

Can't help with the part numbers but the brackets you posted look like what I had.

Am sure there are others and maybe cheaper or more reliable systems too. No complaints yet though!

I would say though, get the proper "mole" type Tec screws (maybe they come with them anyway?) It's an odd job, boring through relatively thick Ali into relatively thin sheet steel. The screws they came with did a decent job of creating an elongated and decent thread in the sheet steel, which a normal one wouldn't have.

 

[knighty]

I'd use unistrut, the hot dip galvanised stuff

using the unistrut type nuts (the rectangle ones with springs on that I don't know the right name of) should make fixing the panels down and lining them up right etc. much easier

held down with tech screws through the ridges

 

[julianf]

I'd use unistrut, the hot dip galvanised stuff

using the unistrut type nuts (the rectangle ones with springs on that I don't know the right name of) should make fixing the panels down and lining them up right etc. much easier

held down with tech screws through the ridges

I think unistrut probably looks like a better plan for the rails, but the other stuff has the panel mounting clips that match up with the rail things.

I could possibly use the same clip things, and attach them to the Unistrut, but without seeing them both in the flesh, its not clear to me.

 

[julianf]

Scrap that, this is the part for the unistrut, right?

Page Not Found - Aliexpress.com

I cant find the end ones though (the above being a middle of the panels clip)

 

[GKQ]

lag bolts.
screw through ridge into purlin. Run support across and fix solar panels to support.

just finished my new solar this week, only water but same idea.
remember to allow for wind lift, recommended here is 130kg per 1m2 of surface area.
graham

 

[knighty]

Scrap that, this is the part for the unistrut, right?

Page Not Found - Aliexpress.com

I cant find the end ones though (the above being a middle of the panels clip)

it looks right... sih... I'm not sure those nuts fit inside unistrut... but the right nuts are pennies, so you could use the top clip bit and the cap head bolt with a unistrut nut underneath

you'll want the unistrut running left to right so those slips are at 90' to them when they're fitted (which is the way I'd assume you'd do it anyway?)

I've never fitted solar so a bit unsure on the right clips etc. wow it's a shame the navitron forum disappeared :-(


got a 3d printer? you could print blocks to use as clips? same as those ali ones but make them solid instead of gap in the middle, use a longer bolt?

 

[Agroshield]

Someone asked on here a few months ago about aluminium Unistrut. It is available and seems geared up towards solar panel and solar hot water uses.

Aluminium Channel. - Blocks - Brackets ,Guards and Blocks. - Product Range

<div><strong><span style="text-decoration: underline;">Features</span></strong></div> <ul> <li><strong>Low-profile, aluminium strut/ channel.</strong></li> <li><strong>Ideal for mounting all sizes of Cushion Clamps/ Hydrozorbs.</strong></li> <li><stro

www.tfsolutions.co.uk

 

[julianf]

Someone asked on here a few months ago about aluminium Unistrut. It is available and seems geared up towards solar panel and solar hot water uses.

Aluminium Channel. - Blocks - Brackets ,Guards and Blocks. - Product Range

<div><strong><span style="text-decoration: underline;">Features</span></strong></div> <ul> <li><strong>Low-profile, aluminium strut/ channel.</strong></li> <li><strong>Ideal for mounting all sizes of Cushion Clamps/ Hydrozorbs.</strong></li> <li><stro

www.tfsolutions.co.uk

One of those companies who cant be bothered to add pricing to their website : (

 

[sparkysy]

I used run through bolts on ours as we have wooden perlins, drove them into the ridges of the sheets as there is less chance of leaking but they were sealed with sikaflex and a rubber cap, I used slotted galvanized unistrut for the rails and the brackets Julianf linked to hold the panels down. They have been up for 12 years so far with no issues or leaks!
Sy