A vehicle door assembly includes a door inner panel that has a header portion that at least partially defines a window opening. A reinforcement panel is configured to abut the door inner panel along the header portion and further defines the window opening. The door inner panel and the reinforcement panel each have a respective first flange extending at least partially outboard and a respective second flange extending at least partially inboard. The first flange of the door inner panel abuts the first flange of the reinforcement panel and the second flange of the door inner panel abuts the second flange of the reinforcement panel. A trim member is secured to the reinforcement panel and to the header portion to cover the second flanges without contacting the second flanges and has an inboard-facing planar portion as a furthest inboard extent of the trim member.