A long time ago, before central air became the norm, ventilation was attained by opening a transom window above the door. This allowed ventilation in bedrooms with the door closed.
Even with central air and heat, a transom will help with air circulation in Rome with the door closed.
So after a night not warm enough to for AC, I wondered if maybe there was a way to provide transom ventilation to a bedroom.
So I got out the tools and started hacking away at the space above the bedroom door.
It has made a huge difference in the comfort of the room with the door closed, wether the AC is on, or the windows are open, we have great circulation in the room with the door closed.