Roofing the greenhouse

After reading through the threads here, and getting the plans Fivekulps provided a link to (thank you!!!!) we are going to build a greenhouse (6x9 or 8x10) and set it on a portion of our driveway where it'll be about 20' from the house, and 5' from an outdoor GFCI plug.

We're wondering about roofing materials though. I see the threads about the plastic sheeting breaking down, so I'm thinking about using corrugated fiberglass roofing for the roof, and plastic sheeting for the sidewalls. Here are some questions I have:

1. Can a greenhouse made of 1" PVC support the weight from this type of roof?
2. How do we attach it to the frame? (I'm thinking self-tapping screws through pre-drilled holes, and possibly expanding foam sprayed in the gaps to seal it....)
3. What to use to cover the roof peak where the sheets of fiberglass will meet? Flashing, perhaps folded over and screwed down? Other ideas?

Any and all other ideas, suggestions or cautions are welcome. We're just starting (haven't cut the PVC yet), so plenty of time for input.

go-vols, my husband used the corrugated fiberglass as flashing. he cut to fit over the peak, but our greenhouse is built with lumber so that might be easier to do that. he said if the rain gets in a little it will not hurt anything because water will be in it anyway lol. we also used the fiberglass for the walls to. it is almost done has good light and boy is it hot in there. sorry if i'm late with this reply i came in to get ideas for how to build my shelves and tables.
farmgirl21

Farmgirl and go Vols,

That's exactly what my hubby is going to do for me! Use the fiberglass sheets. however we are going to increase the size some. I can't wait! Thanks for the plans!

Donnajo

I have some large plexeglass windows in my roof-but the whole thing is made of wood and windows.

I have a green fiberglass roof and white fiberglass sides. The filtered top is great for fers and other shade loving plant, but it doesn`t work very well for starting seedlings. I have been wanting to remove 4 sheets of the green and replace them with clear near the front just for seeds. I have to keep a gro-lite on them now. It is just something to think about if you are going to start fron seeds.