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In our last post we talked about the Doors of Dublin, the world’s largest door and oldest doors. In this post we shall take a look at some other interesting and otherwise unknown facts about doors.

Revolving doors

Rumour has it that the revolving door was invented in a protest against chivalry! In the late 1800s a Philadelphia inventor, Theophilus van Kannel, was affected by phobias, one of which was the ‘etiquette’ of door management (i.e. who should enter or exit first and the expectancy of having to open doors for women).

In 1888 he was granted a patent for the basis of a revolving door called a ‘storm-door structure’ which would eliminate the necessary ‘dance off’ at conventional doors. Ironically, although revolving doors aided one phobia it actually brought about a whole new one which affects many people and leaves them unable to use revolving doors: claustrophobia. In New York the building regulations state that a revolving door should not exceed a speed of 15 rotations a minute.

Door locks

Most doors are fitted with pin tumbler locks that offer substantial security with simplicity of use, and it may interest you to know that this smart idea has been around for 4,000 years. There is historical evidence that ancient Egyptians invented a prototype lock that seems to be the basis of the pin tumbler lock. It wasn’t until 1861 that a locksmith by the name of Linus Yale Jr was granted a patent for the Yale lock that still retains popularity today..

Automatic doors

Although the first automatic doors were invented by a couple of Americans, Lew Hewitt and Dee Horton, historians discovered the basis of the design dating back to 70 AD. The Alexandrian inventor Hero designed, amongst many things, a set of temple doors that would swing open via a system of steam powered weights. This idea of automatically operated doors eventually found its way to the Americans, who produced automatically operated sliding doors to counteract the troublesome habit of swing doors blowing open in the wind. The company was founded in 1960 and still operates today.

Which way should a door open?

Have you ever noticed that the majority of residential front doors open inwards, but public front doors open outwards. Why? On researching this topic, the following fun facts were found. In all Scandinavian countries, all modern front doors open outwards. This is to generate more space inside the hallway or living area if the front door leads directly into the front room. You will find however that older houses have doors opening inside so that people didn’t find themselves trapped inside during heavy snowfall.

In the UK residential front doors open inwards for a few reasons:

  • A front door is a fairly simple design, a panelled board attached to a frame by a few hinges. Removing the hinges allows you to remove the door, which means keeping the hinges out of reach to intruders!
  • People standing outside the door would be an obstruction or at risk of being hit.
  • In narrow streets and blocks of flats there is little room for outward opening doors.

Public buildings door open outwards for security reasons:

  • In the case of a fire evacuating a building would be a logistical nightmare with an inwardly opening door.
  • Intruders would find it much more difficult to force entry through an outward opening door.

So take a  moment to look at your front, patio, interior door and really appreciate it for the little gem it is.

[Photo by tpsdave]