I thought I'd give a follow up on this project.
It's taken me on and off all summer working on this thing. I gave up on it for awhile. I just can't work in this 95+ degree heat and humidity like I used to. And the rain.
I got some sawmill lumber. 16 foot long poplar 2X4s for about $4.50 a piece.
I acquired some galvanized roofing tin that came from an old tobacco warehouse for $300 and I still have plenty left over for another project. Most of it was 17 feet long and some pieces were shorter. So I just overlapped the shorter pieces over the long pieces pointed down hill. I only had to cut a couple of pieces.
Here is where I made my mistake. My father who has built a barn told me to run some 2X6s across the 2X4s to nail the tin to. I thought my measurements were spot on so I placed these 2X4s 36" apart. Well that didn't line up too well. Some of it was due to the fact this lumber is not kiln dried so it warped.
However the roof structure is sturdy enough for me to walk on top of it so it should be OK in case we get a snowstorm.
I covered up any prior nail holes with aluminum tape from the inside then sprayed some expandable foam between the gaps where the tin overlap on the inside and sprayed rubberized undercoating over top of it.
I used some landscape edging to make a skirt to go around where the 2X4s, tin and fiberglass panels meet. This was not worth the effort but may help some of the rain from blowing in.
Now to wait for a hard rain and check for leaks. I'm sure there are going to be some leaks but I'm going to try to shoot some more expandable foam wherever I see a leak. I may have to resort to laying some plastic over my lawnmowers and toys but I think it should be 99% leak free.
The only three things left to do is fabricate a door, run a power cord for some lights and outlet so I can connect my trickle chargers too it and "round off" the tin. Using a reciprocating saw proved too difficult so I'm going to see about getting a metal cutting blade that will go on my Skill saw.
If I had to do it all over again, I'd probably would have had a building built but I got probably $600 in this structure and it's about 400 square feet.
It doesn't look as nice as I had hoped but this was my first structure I ever built. I'm used to working this metal and cars and stuff.
Here's some photos:
https://drive.google.com/open?id=1AVox6kIMd0vYIXHJ9WYe_P9ikLbDm1sH