You might keep your eyes open for old rusty metal grain bins.
The cylindrical ones.
If you can find a farmer that has an old one that is rusted enough that the bolts don't hold it together very well, those old grain bins become unusable. The grain pressure splits the seams and the grain falls out.
Those old grain bins are made like a tank.
The edges of the metal sections and the holes won't have galvanizing on them, so that is where the rust will form, and that is where the bins will fail. However, most of the metal is in great shape.
If you were to consider a barrel vault roof, by using sections of an old grain bin, you might have a nearly indestructible roof for ... well maybe for free.
You might be able to convince a farmer to give you an old rusted falling about grain bin, if you volunteer to take it down and haul it away.
This is super heavy duty guage metal. Not the thin stuff typically used for roofing.
In any case, if you see an old grain bin that's falling apart, take a close look and consider what you might be able to do with most of the metal.
Something like this:
http://s3.hubimg.com/u/1009014_f520.jpg
The upper roof of the bins will rust faster than the walls. When the walls fail, it's at the seams. Think about using the wall panels as a roof, and cutting off the rusty seams or just painting them over with rust inhibitor. There are no rules that say a gable roof cannot have an arc to it.
--- In papercreters@yahoogroups.com, cloud wall <windwalkerwill@...> wrote:
>
> https://picasaweb.google.com/106060429030466659564/20112012BuildingTheShedrow?authkey=Gv1sRgCOPwvOKwz6DkEgÂ
>
> I almost forgot; for all my whining about that billboard roof, it has withstood 70mph winds without a hitch.