What a rekey changes
Inside many common cylinders, small components correspond to the cuts on a key. Rekeying changes that combination so a new key operates the cylinder and the previous key does not. The exterior lock may look unchanged. That is the point: when the hardware is compatible and in good condition, access can change without replacing every visible piece.
Rekeying does not repair every problem. A cracked housing, badly worn cylinder, corroded mechanism, missing part, incompatible keyway, or door that will not align may need another solution. The locksmith should inspect the condition first and explain whether rekeying, repair, adjustment, or replacement addresses the actual concern.
Plan the doors before the keys
Walk the property and list each keyed opening: front door, side door, rear door, detached garage, storage room, office, or common area. Count cylinders, not just doors, because one door may have a keyed knob and separate deadbolt. Note which ones currently use the same key.
Then decide the desired relationship. A homeowner may want one key for all exterior doors while keeping a detached workspace separate. A business may need an owner key and different staff access. More complex hierarchies require careful system planning and compatible hardware. A written door list is better than making those decisions while standing in a hallway.
After a move or tenant change
New occupants rarely know how many copies of an old key exist. Previous residents, contractors, cleaners, pet sitters, relatives, and property staff may have held legitimate copies at different times. Rekeying supported locks establishes a new starting point without implying that anyone misused a key.
In an apartment, condo, or leased business, confirm who controls the cylinder and whether the opening participates in a building system. Management may need continued access or may prohibit unapproved changes. Get written or direct authorization where appropriate and keep the property contact available during the appointment.
Lost keys and access changes
A lost key does not always require immediate rekeying, but context matters. Was the key labeled? Was it lost with identification or an address? Does it open only one exterior door or several properties? Who else still needs access? These questions help the owner decide how urgently the old key should be disabled.
For a business, combine the rekey with a key inventory. Record who receives each new key and recover older copies where possible, even though they will no longer work in the changed cylinders. For a household, label keys discreetly and choose a spare-key plan that does not advertise the address.
Test the system, not just one lock
After rekeying, test every new key in every intended cylinder with the doors open and closed. Check that the bolt or latch moves without pushing, pulling, or lifting the door. If the key turns smoothly while open but binds when closed, the door alignment needs attention; changing the cylinder combination does not solve that mechanical pressure.
Confirm that old keys no longer operate the rekeyed cylinders and that any building, owner, or emergency access that was meant to remain has been preserved. Count the new keys, decide who holds them, and store the plan securely. The value of a rekey is clear access control, not simply receiving a fresh-looking key.