If it is for example, 27 degrees outdoors, and there is any gap between the gasket and the wood siding of the building itself of any kind, it will also necessarily be 27 degrees on the inside of the hose bib protector. There is no escaping that fact. Hoses bib protectors are not magical devices, intended to ward off evil spirits of severe cold. The seal between that black soft neoprene and the building itself must be there, with absolutely no leakage, in order for the hose bib protector to capture the (somewhat reduced) warmth from the exterior wall of the building (at that point, probably 40 degrees at the most), and prevent the water inside the hose bib and the water pipe that it is attached to it from freezing.
