A master key system is a planned hierarchy: each door gets its own key, sub-master keys open defined groups (a floor, a department), and one master key opens everything. Done right, every person carries exactly the access they need and nothing more.
The design phase is where systems succeed or fail. We map your building — units, common areas, mechanical rooms, offices — and build the keying schedule around real roles, not guesses. Built on restricted keyways, the system cannot be quietly duplicated at a hardware store.
Good systems also plan for change. Tenants move, staff turns over, spaces get reconfigured. We document every key and keep the schedule expandable, so rekeying one unit never disturbs the rest of the hierarchy.