I have had conflicting advice regarding fitting locks to an office door in a multi-tenanted commercial building. The door opens onto a common-area stairwell which is the primary escape route.
I have been told that I must have a BS8621 rim-lock so that exit is always possible without the need for a key. This seems fair enough and I accept that.
However, for security, I want a good mortice lock in addition. This needs to be a BS3621 (keyed from both sides) so that an intruder who may have gained access through a window can't then carry his loot out through the door.
I have been told that, if I have this mortice lock, then it must have a thumb-turn on the inside because it's on the escape route, but I have read elsewhere that additional locks may be used whilst the property is unoccupied and fixed unlocked when the premises is occupied (remember this is a commercial property not a dwelling).
I am also of the understanding that the door lock should be EN179 compliant (ie opened from inside using a handle) and that the door should be "operable without requiring people to manipulate more than one mechanism" (Approved Document B para:5.7 iv). So, if I was to have a thumb-turn on the second lock, then the door would no longer meet Building Regs as there would be two locks to manipulate.
Am I right in my understanding that, whilst unoccupied, I can secure the door any way I choose? And, if so, where can I find this written?
Many thanks for any input.
