An embodiment of a closed-cell polymeric rigid foam may be made using a one-shot method and a reaction system that includes a hydrofluoroalkene physical blowing agent and a polyol mixture having an aminic polyol. The hydrofluoroalkene blowing agent has 3 to 5 carbon atoms and a boiling point between 10° C. and 40° C. at 1 atmosphere pressure. Embodiments of rigid foams may have high closed cell content and are particularly well suited for thermal insulation.