Super fun fact time! Do you know why revolving doors were invented? Not because they look cool, but as a way to open the doors in a building with pressurization issues. Have you ever been a building where doors slammed by themselves, or you noticed a door that seemed hard to open, or would not stay shut? Well, those events are actually symptoms of pressure issues. Airflow is not moving through the building correctly and creating pressurization issues. The trickiest of these issues is doors not opening. If the building is tall enough and the pressurization issue is severe enough, the doors were just hard to open. You want your building to have proper airflow. It is important for the health of your building and it is important for the efficiency of your HVAC system. The Revolving door is way to enter and exit without the impact of pressurization. If you want a quick “cheat” when evaluating a building to see what the airflow is like, go through the side doors. If you have trouble opening the door (or getting it to shut), this will be a clue of what type of work you may want to invest in.