Metal building condensation

Yup. All this works exactly like a cold beer. The beer can is the inside walls of your shop, and it also represents the tools in your shop. The place you are in with the beer represents the inside air of your shop.

The warm air in your shop is humid, and it condenses on the cold walls of the shop (beer can) as well as the cold tools / parts (beer can)

I think down there you would need a double vapor barrier (inside and out) to do things right.

Not insulating the ceiling would be a mistake.