Did I really......one of my better comments thenI've built sheds/lean-tos(and trailers(!)) out of garage doors - frames usually 40mm angle.
You don't get much more agricultural than that! ( Or "Soweto" as i believe @TechnicAl described it )
https://www.mig-welding.co.uk/forum/threads/building-a-big-shed.95531/#post-1427841Did I really......one of my better comments then