Revolving Door

Why was the Revolving Door Invented?

Theophilus Van Kannel invented the revolving door in 1888 because he was annoyed with opening doors for others and the cold air that came in each time. He wanted a solution that would let people enter and exit a building at the same time without having to hold a door open for someone else, while also preventing drafts, snow, rain, and street noise from getting inside. The invention also served as an early airlock, which helped with energy efficiency by minimizing heat loss.  

• Creator: Theophilus Van Kannel, an American inventor. 
• Invention date: He received U.S. patent 387,571 for his “Storm-Door Structure” in 1888. 
• Motivation:
  • Social: He disliked the social custom of men opening doors for women and the awkwardness of “door-holding standoffs” with other men. 
  • Practical: He wanted to prevent the inconvenience of cold air, snow, rain, and street noise from entering a building. 
• Early use: The first revolving door was installed at a restaurant in Philadelphia, where Van Kannel lived. 
• Benefits: The design allowed people to pass through at their own pace and simultaneously without collision, while also serving as an energy-efficient airlock that kept the elements out.