In article , Roger Mills
writes
In an earlier contribution to this discussion,
Dave Baker wrote:

"Roger Mills" wrote in message
...

Does yours look anything like this?
http://www.idealhomeaccessories.co.u...r_Mortise_Lock.
html

It's that kind of thing yes. Mortice at the bottom, latch at the top.
My key has only 3 prongs on it though and I've just had a measure and
it's exactly 45mm from the edge of the door to the centre of the
keyhole. So it's looking like a standard 67mm lock then? Every
dimension will be the same in a new lock?

That's a good start, but there are other dimensions which might vary - like
the vertical distance between keyhole and latch. They're all shown in the
link posted by 'Geo'.

I think the strike side will almost certainly need opening up, the
deadbolt width increased a bit with the 2004 revision of BS3621 so
things had to move to accommodate it. At least the strike side is the
easier one to modify. The strike box will be deeper to take the longer
throw too.
--
fred
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