John wrote:
I just wondered why Yale locks were always fitted at eye level but
mortise locks were fitted half way up the door (traditionally)

You can't fit a mortice lock at or near a mortice & tennon joint in the door
cos it weakens it, so it has to go above or below. You can fit a Yale
almost anywhere.

So for max security on a door with a M&T joint halfway ish up it makes sense
to have one lock below & one above the halfway ish point. Since the Yale is
used more frequently it makes sense to have in in the top half.


--
Dave - The Medway Handyman
www.medwayhandyman.co.uk