Z bracket panel mount question

Sagecoachdriver wrote:
Fiberglass dimpled roof. Forest River Forester

Ah, those are different. Very few of them are structural fiberglass - Escape, Casita, old Burro and few other. The majority are thin fiberglass over thin plywood, with struts underneath. I don't know if it will hold #10 screw without being anchored to the strut (which may not be always possible). As I recall, people used double-sided 3M VHB tape AND fasteners at the same time. There were few installs here on these roofs, Bigfootford is one of them. Check his photos on The List.

I initially thought of making something like his, but then went for a simpler install, with L-brackets only, no short legs attached to L-brackets, no clevis pins, no play.


Had to be 4" tall bracket to clear plumbing vents under the panel. Can tilt it if I want, but don't have to, plenty of charge when flat. It is tilted on the photo. 6 screws were also meant for wind loads on this 245W big 65"x40" panel when tilted, 3 of them are in the strut. For a lower bracket this is overkill, but - the Big Plan was to have it tiltable to either side, i.e. this bracket - in theory - could be used as tilting arm support. All this ended up being used as flat only, so if I had planned it as flat from the beginning, it would've been 4 screws max. In the panel I put a 1/4 stainless Rivet Nut - aka Nutsert, so I can drive the screw in or remove it from outside, there is no nut on the other side.

This time of the year,if you get out in the desert all around Quartzsite, you'll see thousands of RVs, most solar powered, and most all panels are tilted.

Don't drill more holes in panels because it weakens the frame ??? Never saw such a thing on my ijit sheets. Nor would I ever buy a panel that would be weakened by drilling a 1/4" hole.

In reality those kind of instructions are there for ijits that can't drill a hole w/o breaking the glass

Almot wrote:
About tilting - while it's nice to have this option, you'd better estimate your solar harvest VS your energy needs and think twice before going for tilted design. It's easy enough to install more flat panels. Climbing the roof and working there with tilting you can once or twice a year, but you won't enjoy doing it if you move around often. I've made my panels tilting to the sides, but don't use this feature because 490W flat works well for me.

+1

With the price of panels dropping spend the money on more panels as opposed to a tilting mechanism.

Going up on the roof to change the panel angle gets old real fast. I'm betting most people with tilting panels don't bother after awhile.

Ron W.

Fiberglass dimpled roof. Forest River Forester

Sagecoachdriver wrote:
Last time I was up on the roof, I noticed a blue marks along the side where the roof curves for the side, I bet they are where the roof struts are.

Blue marks, like from a marker? If this is EPDM/rubber over plywood, this is odd. When they roll the EPDM over, the plywood is already nailed to the struts so there is no need to mark anything. I can see my struts under the rubber and plywood when roof is wet. I can also see where they are, by rows of screws (under the rubber) scattered in chaotic manner by $8/hour laborers of the venerable Dutchmen/Thor RV corporation. But I didn't notice any marks.

It can be difficult to locate the struts under plywood accurately. You can locate the screws, by running a small rare earth magnet along (available for $1 at most hobby and carpentry stores). My $70 top of the line stud finder - ultrasonic, not magnetic - could not find the wooden stud under 5/8" particle board and rubber with better than 1 or 2" accuracy - with 1.3/4" stud such an accuracy is useless.

If you decide to try and hit the studs/rafters, after you've located and marked the rafters, it's better to attach the brackets to panel first, and then put it down to see where they are on the roof. Then you mark and drill the holes in the brackets for #10 tapping screws into roof.

BFL13 wrote:
Some (all?) panel instructions say never drill more holes in the frame or it will weaken the frame.

Don't remember such a warning in my panels by REC of Norway. I took my time when choosing brand and frame profile. Some frames are weaker than others.

Besides, after inserting a stainless rivet nut into the panel side, I think this spot is now "at least" as strong as the aluminum profile before.

When panel is installed flat (=tilted 3-5 degrees for water drainage), and sitting low on aluminum brackets a few inches from the roof, there isn't much wind stress on it. Of course you can break anything. Once or twice I almost sat/fell on the panel when walking around, tidying up the wires etc. It's better not to walk up there too often.

Last time I was up on the roof, I noticed a blue marks along the side where the roof curves for the side, I bet they are where the roof struts are. Good Idea to fasten angle irons to them

Some (all?) panel instructions say never drill more holes in the frame or it will weaken the frame.

So if you go the side route, you need more holes. If you line up the bottom holes with the roof struts and you can't, you need new holes.

You can beat all that by having the roof attachments (rails, eg) to the struts and then you can space the existing holes in the panel to anywhere along the rails.

That still leaves how to get the panel off the rails without so much trouble. Depending on your set-up, you can use the two-bracket method or leave the bracket on the panel and undo from the rails

Which saves you from ripping up the Dicored roof attachment the other way with Z brackets.)

"It depends" (as usual).

Right on,
I tilt my panels when setting 2-3 months in Arizona.
I never tilt for 2 or 3 days.

About tilting - while it's nice to have this option, you'd better estimate your solar harvest VS your energy needs and think twice before going for tilted design. It's easy enough to install more flat panels. Climbing the roof and working there with tilting you can once or twice a year, but you won't enjoy doing it if you move around often. I've made my panels tilting to the sides, but don't use this feature because 490W flat works well for me.