We would like to get cellular blinds to reduce the cold and heat loss through our drafty windows; however, the molding/frame around our windows is shallow so cellular blinds will not fit inside the frame. They will have to be “Outside” mounted to the frame. Will this have the same insulating qualities as if they were installed inside the frame? The ends of the cellular blinds will be open since it is outside mounted and it seems that since the air is not trapped in the cell perhaps the insulating properties will not be as great? Is it worth getting cellular binds for insulation even when the ends of the cells will be open?