Guide
Master Key Systems Explained: How Buildings Control Every Door
How does one key open a whole building while tenants open only their doors? A plain-English guide to master key systems.
A master key system is a designed hierarchy: each door gets its own key, and higher-level keys open groups of doors. Tenants open only their apartments; the super's master opens the whole building; the owner's grand master opens everything across multiple buildings. The hierarchy is drawn up on a keying schedule before a single pin is cut.
The security of the whole system rests on key control. Every cylinder in a proper system uses a restricted keyway — blanks available only through authorized dealers, duplicates cut only with authorization. Without that, anyone copies a key and the hierarchy is fiction.
Systems need maintenance: rekeying when staff leave, new cylinders for renovated spaces, and accurate records of who holds what. We design, install, and service master key systems for co-ops, condos, offices, and brownstone conversions across the Upper West Side — call (646) 469-7112 for a survey.
Frequently asked questions
What is the difference between a master key and a regular key?
A master key is pinned to open multiple locks in its group; a change key opens only its own door. Both are part of one designed system.
Can tenants copy their keys at a hardware store?
Not in a proper system — restricted keyways make unauthorized duplication impossible.
What happens when an employee leaves?
Rekey the affected doors. Their key stops working everywhere, and restricted keyways mean no secret copies.
How do we keep track of all the keys?
With a keying schedule and issuance records — we provide both and maintain them as the system grows.