I kept my R22 in a cow barn together with the cows for a couple of winters and never had any condensation problems. The barn was made of breeze blocks for the first 10 feet then wooden slats with holes between them up to the steel sheet roof. When the farmer sold his barn, I moved it to a shed with steel side and a steel roof. This gave me condensation for about 2 weeks in the winter.
I have just had a new steel framed shed put up at my house. This has shiplap boarding on the sides and a steel roof. There are small gaps in the sides which will certainly allow it to ventilate and I am debating whether to line it internally with plywood and loft insulation fibreglass.
I would welcome any opinions.