I'd be careful about hangare beside a mob of cows, uric acid etc. same re a shed that has been used to store fertilizer in.
Seriously,there is a bloke over there Nigelh I think his name is. He is an ace on hangar construction, its a wonder he hasn't come along with a bit if friendly advice by now. As a tip don't tell him it's for an R22. That should get him talking. Tell him all of us R22 mob miss him.
tet