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Berlin Key

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Re: Berlin Key

#41

Post by IshKebab »

Someone wrote: post #17

The English description on that page doesn’t make it easy to understand what this key does. ”Its name comes from the fact that it has two key blades (the part which activates the bolt) at each end of the key, rather than the usual single blade” How does that lead to the name “Berlin key” or either of the German names? I would guess “Berlin key” comes from the fact that it predominantly is used in Berlin. ”After unloc…

I agree it is really hard to parse. I think you're almost right. I'm pretty sure it's like this:

1. You can only remove the key if it is locked. 2. You can't lock it unless the door is closed.

That ensures that when you have the key then the door must be locked and closed.

The think about pushing the key through they door is just because otherwise you have no way to start inside the room, unlock and open the door, and then lock it behind you. Remember while the door is unlocked you can't remove the key. So if you just go outside and shut the door the key is now inside... and the only solution is to pull (or push) the key through to the door to the outside. Then you can lock the door and remove the key.

Re: Berlin Key

#42

Post by atoav »

_jal wrote: post #22
decebalus1 wrote: post #15

Earlier quoted context omitted.

Don't know about Switzerland, but as an European living in the US, I think the American fire safety rules are what they are mainly because most houses here are basically matchstick houses built from prefab low quality wood which would get devoured by flames in minutes. And the fire-resistant building materials are super toxic when they actually burn. So fire is a very big deal... Anecdotal, we had a fire in my buildi…

I stayed in a house in Germany in which the walls were filled with dried-straw for insulation. It was several hundred years old. There was a no-smoking rule.

> There was a no-smoking rule.

Which to be honest says not a lot about anything, because this isn't that unusual in Central Europe.

Also: a lot of the old wooden houses are far better in terms of fire resistance than you'd suspect on first glance, wood often outperforms concrete and steel when it comes to structural integrity in a fire.

I don't know about the straw thing, I only know it mixed with clay.

Re: Berlin Key

#43

Post by wazoox »

School-Cotton wrote: post #26
chrisseaton wrote: post #25

Earlier quoted context omitted.

> As it's impossible to leave the building without a key in case of a fire. Isn't that the case for most doors that lock? You can't leave through my (brand new, to-code) front door from inside without a key to unlock it first. It wouldn't be secure if you could open it without a key - isn't that the whole point of a lock with a key?

What country do you live in? In the US, almost every door I’ve ever seen can be unlocked from the inside (but not the outside) without a key.

I've never seen that outside the US. Keyholes both sides of the door, everywhere. When it's closed, you need a key or you don't get out.

Re: Berlin Key

#44

Post by [deleted] »

cj wrote: post #30
chrisseaton wrote: post #25

Earlier quoted context omitted.

> As it's impossible to leave the building without a key in case of a fire. Isn't that the case for most doors that lock? You can't leave through my (brand new, to-code) front door from inside without a key to unlock it first. It wouldn't be secure if you could open it without a key - isn't that the whole point of a lock with a key?

> You can't leave through my (brand new, to-code) front door from inside without a key Just to clarify, after you lock your front door with the key, it’s impossible to unlock the door from the inside without a physical key? The vast majority of locks have a physical unlocking mechanism on one side (one side is unprotected, usually the inside)

[deleted]

Re: Berlin Key

#45

Post by School-Cotton »

chrisseaton wrote: post #35
School-Cotton wrote: post #26

Earlier quoted context omitted.

What country do you live in? In the US, almost every door I’ve ever seen can be unlocked from the inside (but not the outside) without a key.

The UK. What stops someone breaking glass or a panel and reaching through and unlocking to get in quickly if you can open without a key?

> What stops someone breaking glass or a panel and reaching through and unlocking to get in quickly if you can open without a key?

I suppose this can be avoided by not having any windows close enough to your doorknob that you could reach the lock from them. But people could just break a window and climb through into your house, anyway.

Re: Berlin Key

#46

Post by School-Cotton »

wazoox wrote: post #43
School-Cotton wrote: post #26

Earlier quoted context omitted.

What country do you live in? In the US, almost every door I’ve ever seen can be unlocked from the inside (but not the outside) without a key.

I've never seen that outside the US. Keyholes both sides of the door, everywhere. When it's closed, you need a key or you don't get out.

Well, TIL. Never realized this was a US-specific thing.

Re: Berlin Key

#47

Post by jwilk »

Someone wrote: post #17

The English description on that page doesn’t make it easy to understand what this key does. ”Its name comes from the fact that it has two key blades (the part which activates the bolt) at each end of the key, rather than the usual single blade” How does that lead to the name “Berlin key” or either of the German names? I would guess “Berlin key” comes from the fact that it predominantly is used in Berlin. ”After unloc…

> Its name comes from the fact that it has two key blades …

Until recently, this sentence used to be “Its particularity comes from the fact …”:

https://en.wikipedia.org/w/index.php?title=Berlin_key&diff=9...

Re: Berlin Key

#48

Post by mpweiher »

My house in Berlin, the Corbusierhaus[1][2], used to have this type of key for the front (car) gate.

The gate was usually open, and then couldn't be locked with the key. If the gate was closed, it could only be left again in the closed state.

The house is next to the Olympic Stadium, so the gates are closed when there's a football game, concert or other event.

[1] http://www.corbusierhaus-berlin.de

[2] https://en.wikipedia.org/wiki/Unité_d'Habitation_of_Berlin

Re: Berlin Key

#49

Post by ghshephard »

chrisseaton wrote: post #35
School-Cotton wrote: post #26

Earlier quoted context omitted.

What country do you live in? In the US, almost every door I’ve ever seen can be unlocked from the inside (but not the outside) without a key.

The UK. What stops someone breaking glass or a panel and reaching through and unlocking to get in quickly if you can open without a key?

You either have strong or no glass on or near your front door.

I have never seen an exit door in Canada, or the United States, that could not be opened from the inside. I'm reasonably confident that is super illegal in those countries.

Re: Berlin Key

#50

Post by zaarn »

odiroot wrote: post #10

I'm surprised some houses still use this. As it's impossible to leave the building without a key in case of a fire. I suspect it may even be illegal today.

Fire control rules are somewhat different between the US and Europe. In Germany, such a system would be fine. Depending on the door even encouraged.

A large part of German Fire Code is to prevent the spread of the fire and contain it in the rooms where it started for as long as feasible. The lowest rating a fire location can have is E30, meaning the fire takes 30 minutes to "break out" and spread further. The building owners likely also benefit from grandfathering (ie, special building fire code, which depends on federal state in germany).

It also depends on the fire load, ie, how much flammable material the house contains. A concrete or stone house that contains only flammable material as part of furniture isn't a huge fire load and you don't need heavy doors to prevent fire from spreading out of a single flat, a normal door will likely already prevent spread.

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