Strength of Roof and Solar Install question

It seems to me if you walked on the roof it has to be stronger than 1/8 inch luan with supports 4 feet apart.

Our MH has a metal roof, less than 1/8 inch I think. I did go up on it when we first got it and I think I broke one of the supports. The metal drooped so a puddle formed when wet. I fixed it by opening the ceiling and putting a piece of wood on top of the too low support oriented front to back and extending from 1 crosspiece forward of the bad one back to the one behind it.. After that when I went on the roof I put a couple of 2x6 planks across the width of the roof and scooted out on a sheet of plywood on the planks.

I meant to work inside the ceiling and run metal joists on each side of that crosspiece but never got around to it.

When installing our one solar panel, I discovered that the rear portion of the roof was stronger built with heavy plywood over the wood crosspiece supports. I ran two of the panel frame screws into that and another two into another cross piece support forward of the plywood. The four good sized screws are adequate - no sign of movement or looseness. I don’t go over 60 mph and go at 55 if traffic permits. I can accommodate another panel the same way but don’t need it - 100 watts is perfectly adequate for our small MH and two of us.

Newbiecampers wrote:
Any thoughts or real-world experiences with that thin of a roof along with a solar panel set-up?

I have a Chevy based Coachmen Freelander and helped a friend who also has a Freelander mount solar panels on his rig.

Using 1" X 1" angle iron, we welded up a framework in which the side-to-side rails overhung the width of the RV and turned down. After power coating white, the rails were bolted through the sidewalls into the studs.

All of the framework and solar panels are rearward of the awning.

The electrical wiring was run down the outside backwall (by the ladder) in a wire moulding and forward under the RV. The wiring was then brought up into the RV through the floor.

The frame was 1" above the roof (NO weight on the roof) and there were NO roof penetrations, so no leaks.

The electrical panel was mounted in the storage area under the bed near the water tank.

4 years later, it still works well. For occasional cleaning, he climbs the ladder with a Swiffer in hand.

If doing it again, we would design the framework so that it would tilt to track the sun.

Tim

No problem with ours, I used a sealing adhesive for the screws and Dicor over that.

That's what I have and 4 brackets with 2 lag screws each work fine. Whether you can walk on it is largely a function of your weight.

Your roof does seem thin but don’t over estimate the wind forces on solar panels. Passing over and under reduces the force significantly. However, I’d screw to the aluminum supports and install 300 watts but wire for four. I wouldn’t walk on your roof at all.

You’ll love solar. My batteries are almost always full by 1 pm.