In relation to insulating a skillion roof, there are a number of insulation products available. These contain rigid foam board insulation, for instance EXPOL polystyrene and Mammoth skillion sections; and batt or blanket insulation, for instance Jet Stream® MAX and GreenStuf array. Super-tender Earthwool® glasswool insulation is likewise an option. https://directory-store.com/listings13029328/how-to-insulate-roofs-options