If you manage a small apartment building, an office with several rooms, or a few rental units, you probably carry too many keys. A master key system fixes that: each door keeps its own key, and one key opens them all.
Here is how it works, who it suits, and how to set one up so it stays under control.
How a master key system works
Each lock is pinned so that two different keys can open it: its own key, called the change key, and the master key. A tenant's key opens only their unit; the owner's master key opens every unit.
Larger systems add levels. A grand master opens everything, a master opens one floor or one group of doors, and each change key opens one door.
Who it suits
- Small apartment buildings and rentals, where the owner needs access to every unit.
- Offices with several rooms, where managers need every door and staff need only their own.
- Buildings with shared spaces: storage, utility rooms, mailrooms, back doors.
- Any property where the key ring has become a problem of its own.
Plan it before anyone touches a cylinder
A master key system is only as good as its plan. Before any lock is rekeyed, it is worth writing down:
- Every door that should be in the system, including the ones you rarely use.
- Who needs to open which doors, now and in the likely future.
- Doors that should stay outside the system altogether.
- How many keys of each kind will be issued, and to whom.
How master key systems go wrong
- Doors are added one at a time over the years, with no overall plan, until the keys open doors nobody meant them to.
- Master keys are copied at a hardware store and nobody knows how many exist.
- Nobody keeps a record of which key goes to which door.
- A master key is lost and the locks are not rekeyed.
Keeping it secure
- Keep a key log: who has which key, and when they got it.
- Ask about high-security cylinders with keys that ordinary key shops can't copy.
- If a master key is lost, rekey the system. A lost master opens every door.
- Rekey a unit's lock when a tenant moves out, so the old tenant's key stops working.
What to expect when we set one up
We walk the building with you, list the doors and who needs what, and plan the system before rekeying anything. Then we rekey the cylinders on site, cut the keys, and test every key in every lock it should open, and in the ones it shouldn't.
