Residential doors open in, while public doors open out. There's a reason for that.

Have you ever wondered why the door to your house opens in – while public doors usually open out?

Hopefully, the doors to your house open in. Residential doors are designed that way because doors are relatively easy to take off the hinges. That’s really convenient if you have a refrigerator to get into the house. If your door were hung the other way around, it would be really convenient for robbers.

Public buildings, on the other hand, have other factors to consider when installing doors. It’s assumed there could be a lot of people in there at any given time – and effective emergency exits must have doors opening outwards for a more efficient mass exit. Most public doors have elaborately concealed or protected hinges to prevent removal, which are much more costly than the simple pin-hinges on our own doors.