Rekeying and lock replacement, although often envisioned to be the same, are much different processes and should be used in different circumstances. Here I will outline the differences in each of these processes, and explain a situation where each one would work.
Rekeying is a matter of completely reconfiguring the tumbler, which is the internal structure of the lock. Locks work through a network of internal pins and openings; only a set and very specific aligning of these will cause the tumbler to decompress and unlock. Rekeying is done without having to replace the existing lock. The pins and openings of the lock structure are placed in a new order specific to a new key, while maintining the appearance of your door. Old keys will be useless, and only the new key provided to you will work.
Lock replacement is done by completely removing the entire lock structure and replacing it with a new one. There is a large variety of different lock types to choose from, including electronic options. Replacing a lock needs to be done precisely, and so is best handled by a professional.
WHICH TO CHOOSE
You should rekey your locks when:
It is a common, inexpensive process that greatly increases the security of your home or office.
Replacing a lock should be done when:
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