Have you recently moved home or business premises, and not sure how may keys are in circulation?
Firstly you probably want to check that they are of a reasonable quality. If you check the forend of the lock it should be stamped with a BS kite mark. This will normally include what revision the lock is. The British Standard for mortice locks is 3621: the next four digits tell you the revision eg 1998. So if it’s stamped BS3621:1998 this indicates that the lock conforms to the British Standard as at year 1998, the latest revision was 2007 so BS3621:2007.
Most insurers now specify British Standard locks on their policies, this is a change from older policies that just asked for a five lever lock. On some of the newer policies I’ve seen they are also now specifying the year of revision. It is important to check your own policy, especially when renewing. If you’ve used the same insurers for years you may find the specification for the policy has changed.
If you have a lock that will satisfy your policy requirements you won’t necessarily need to go to the expense of buying a new lock. It is possible to change the lever pack in most locks and this will ensure any old keys will no longer operate the lock. If lever packs are not available a locksmith should be able to change the position of the levers in the existing lock and make new keys to suit, thus achieving the same result i.e. the old keys no longer work.
On occasion this option may not be viable due to excessive wear of the lock. I recently changed over an old Chubb lock that had been manufactured in 1984 (the year of manufacture is stamped on a moving part in the lock) for a new one as the wear was so bad, I could not get it working smoothly without jamming. The replacement lock has a retail price of £157.31 + VAT. This is expensive when you can get a mortice deadlock that conforms to BS3621:2007 for £25.06 + VAT, but I doubt the cheaper one is going to last 34 years. If the original lock had not been as worn, a new lever pack would have been £41.26 + VAT which as you can see is a considerable saving. If you are going to go this route I would advise changing the bolt thrower (curtain) at the same time as this is the part that wears most often as it is constructed of a softer metal than the harder case it is located and runs in. Bolt thrower for the above example is £10.19 + VAT RRP.
If you Do have this type of lock and are going to speak to your locksmiths about it, it is a good idea to have some basic information for them, for instance is it a sashlock or a deadlock? A mortice sashlock will have a latch incorporated that is normally operated by a pair of handles and as keyway. If the handles are set further back on the door (normally a knob) from the keyway this is an “horizontal mortice sashlock”. If the handle is above the keyway it is normally just described as a “mortice sashlock”, in both cases their are various backsets, this is the distance from the front edge to back of lock. Standard sizes are normally 65mm or 77.5mm, the easiest way to determine what size you have is to measure from the front edge of the door to the centre of the keyway. If it’s either 2 1/2″ or 3″ (65 or 77.5mm) the measurement will be approximately 44.5mm or 57mm,see above picture. Don’t be too daunted, if it’s about either of those measurements you’ll be close enough. If you tell me you have a 42mm or 47mm measurement I’m going to take it as a 2 1/2″ (65mm) backset lock anyway. These measurements also apply to “mortice deadlocks”. A deadlock has no handles and will not hold the door shut without locking it with the use of the key. If you have a deadlock you’ll normally have a second lock on the door, most probably a nightlatch. If you look at the forend of the lock with the door open it will normally tell you what make you have, generally above the kite mark. Remember not all nightlatches are Yale and not all mortice locks are Chubb. In actual fact Chubb have not made the locks for years, and most Chubb marked locks in use now were made by Assa Abloy, and in recent years have been re branded as Union. This applies to all ex Chubb door locks, the Chubb window locks etc. are now branded Yale.