Mounting Kyocera panels on metal roof

sundownr
sundownr Solar Expert Posts: 25
roof.jpg

Given this metal rood what would be my best mounting option for eight 245 watt Kyocera solar panels.

Thanks.

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,422 admin
    Re: Mounting Kyocera panels on metal roof

    Hope it is not as shaded as it looks in the photograph.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • rollandelliott
    rollandelliott Solar Expert Posts: 834 ✭✭
    Re: Mounting Kyocera panels on metal roof

    how much $$$ do you have to spend on it?

    cheapest solution would be to throw a couple of treated 2x6's up there.
    Use angle brackets and some lag bolts to attach 2x6's to trusses
    silicon it good
    then use angle brackets to attach solar panels to the wood.
    never have done that, but it should work. there's a guy on youtube that did something similar.

    next step up is to call up an aluminum extrusion company
    http://www.zycon.com/Products/US-NM-New-Mexico/Aluminum-Extrusions.html
    has a list of them close to you and order some 1.5" x 1.5" x 1/8" aluminum angle
    4 pices 12' in lenght would probably work. You could drill that directly to your trusses or get fancy and raise it 4 to 6" off the roof.

    highest cost is a dedicated system like unirac, jackrack, schletter, etc, etc.
  • sundownr
    sundownr Solar Expert Posts: 25
    Re: Mounting Kyocera panels on metal roof

    This is only sample of roof... shade is not an issue.

    I guess it does boil down to using wood or aluminum. I would prefer aluminum if I could find right sort of rail (brackets).

    I had planned on using a wood spacers (pressure treated 2x4) between the roof ridges to provide an even, sturdy base.

    Thanks for the input.
  • solarix
    solarix Solar Expert Posts: 713 ✭✭
    Re: Mounting Kyocera panels on metal roof

    Use what is called saddle blocks (buy or make from aluminum channel) to straddle the corrugation bumps so that your lag bolts can go through the high points of the corrugations to ensure against leaks and won't block the drainage.
    I use stock aluminum 2" angle as mounting rails, then drill&tap 1/4-20 holes at the edge of each module and top clamp them with S.S. bolts and fender washers. Simple and fast. Can either have the rail stick out at the row ends and use the common end clamps or I make a custom clip (out of the same rail material) that grabs the underneath flange of the module and also hides the rail end. Much nicer.
    I know - its not the anodized expensive preengineered mounting system that the AHJ's like to see, so what - better, cheaper, faster.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,422 admin
    Re: Mounting Kyocera panels on metal roof

    Wood is going to be tough... If you use pressure treated lumber, the chemicals/metals typically used to treat the wood can be very corrosive to any touching metal hardware (need to use pressure treated rated strong ties and screws/bolts). I would worry how it would react with your metal roof.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Mounting Kyocera panels on metal roof
    BB. wrote: »
    Wood is going to be tough... If you use pressure treated lumber, the chemicals/metals typically used to treat the wood can be very corrosive to any touching metal hardware (need to use pressure treated rated strong ties and screws/bolts). I would worry how it would react with your metal roof.

    -Bill

    I'll tell you how it will react: PT lumber is full of copper-based chemical. Place on top of zinc galvanized steel roofing. Add rain water. Watch the roof dissolve. :cry:

    Aluminium and galvanized will not play nicely together either. Some insulative material between will be needed, as well as stainless steel hardware.

    Check the structure underneath to make sure there's something to bolt the panel mounts to. This type of roof is very often light weight, consisting of 2x4 trusses an 1x3 furring strips that the corrugated metal is fastened to with small nut-head screws & rubber sealing washers. In other words it's not meant to have a few hundred pounds of solar panel added on and some structural re-enforcement made be necessary. Just because it doesn't sag now doesn't mean it won't sag later.
  • Solar Guppy
    Solar Guppy Solar Expert Posts: 1,989 ✭✭✭
    Re: Mounting Kyocera panels on metal roof

    Never ever use PT lumber, it will warp like a pretzel and shatter the PV's in the process

    The lowest cost option I use is 2x4 aluminum screen enclosure rails and home depot gutter clips. Just replace the lag screw with a grommet screw used for the metal roofing?

    The 2x4 is used as it is shared between rows in my case 5 rails for 4 rows, a big cost savings. I buy from a wholesalers local, not HD or Lowes on the aluminum rails and Capri clips and self tapping hardware.
  • waynefromnscanada
    waynefromnscanada Solar Expert Posts: 3,009 ✭✭✭✭
    Re: Mounting Kyocera panels on metal roof

    I've used PT wood to reinforce the aluminum rack that my panels are mounted on. Warping was definitely not a problem with mine, (perhaps a different climate?) or any PT I've used, HOWEVER, as mentioned, will result in corrosion if up against the aluminum, BUT that is easily cured with a strip of plastic construction tape between the PT wood and the aluminum. Been there, done that with great results.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Mounting Kyocera panels on metal roof

    A little info on PT lumber.

    There are different grades of the stuff, ranging from "high humidity" to "marine use" (numbers 1 through 5, with letter annotations). Most of what you get out of the big lumber yards is #3, suitable for ground contact. If you've ever cut it you will notice the green doesn't go all the way through, and they sell you cans of "cut seal" just for that.
    What's more, the pressure-injected chemicals don't last forever. They do leach out over time, and as that happens the quality rating of the PT drops. If you sprinkle water on it the water should bead. If it goes flat and soaks in, the wood needs some new preservative applied (standard waterproofing seal, stain, or paint). At that point it isn't much different than regular lumber, aside from retaining a certain unpalatable-to-bugs quality.

    The more severe the climate, the faster it ages. I should imagine Florida's combination of dousing rain and searing heat would ring the preservative out of #3 in fairly short order. After that it will warp, check, crack, et cetera. No doubt this is what Solar Guppy has experienced.

    You could use cedar for this same application, but I wouldn't recommend that either. More expensive than PT and you don't get the quality anymore. Once its natural oils have leached it too becomes as ordinary wood. The younger processed trees you get these days don't last as long as the old milled stuff did. In the meantime you'd be watching the brown stain ooze down your zinc-coated roof, which wouldn't be pretty. Also some people (like me) are allergic to it, which makes handling problematic. PT dust should be avoided too, for that matter, as it is toxic.
  • DavidOH
    DavidOH Solar Expert Posts: 112 ✭✭✭
    Re: Mounting Kyocera panels on metal roof

    I went ahead a bought the brackets for mine:
    http://www.solar-electric.com/uni-gr-02.html

    I have only four panels, so you might want another selection.
    That roof looks like mine in my picture.
    Now how will I mount the brackets to the roof?

    I think solarix has the method I will use.

    I'll check back here for the others comments.


    Kyocera 135 watt x4
  • Jburgess
    Jburgess Solar Expert Posts: 130 ✭✭✭
    Re: Mounting Kyocera panels on metal roof

    I used stand offs and boots.

    PICT0582.jpg

    Here’s photos with and without the boots.


    0427111848a.jpg

    0427111847.jpg