Some time ago I found an image of a very unusual arrangement at 20 Union Square, New York City. Originally the Union Square Savings Bank (1907) and now the Daryl Roth Theatre at 101 East 15 Street.

What’s very odd is, first the “vault” looks about the size of a broom closet. Then on the right is what appears to be an emergency door (another image also shows a day gate). This just didn’t make any sense to me. The most likely explanation, to me, is:
- This is not the main door. The main door is a double (or “vestibule”) door located nearby.
- The bank also wanted an emergency door which of course means it has to be as fire/burglar proof as the main door. A standard emergency door wouldn’t be adequate, at least not in 1907.
- So the vault engineer (Holmes) used a standard outer door. To save a little money, instead of a standard second door, he put an emergency door inside a tiny vault behind the “emergency main” door. At least, I hope the very small room is hard to break into if a bad guy tries to go around the big door, and if he does get into the tiny room it has to be hard to go around the emergency door.
As I said, this is unusual. I don’t believe I’ve ever seen this arrangement elsewhere.
I have no idea what the current building is like. I’d like to think all the doors are still there but it’s just a hope.
Comments or other theories are welcome.