Luke insulation is widely used here. Batts of fibre will be layed on the ceiling itself. Rolls of foil-backed fibre are sometimes used directly under the steel sheeting especially in large sheds without a ceiling.Bill, is your climate so mild all year that no insulation is used?
It looks like they are going to put in the ceiling and there is no insulation beneath the roof. I would think that lets a lot of heat in.