Planning a Master Key System for High-Rise Buildings

High-rise buildings present unique challenges for master key system design. With hundreds of units spread across dozens of floors, plus common areas, mechanical rooms, and amenity spaces, the complexity can quickly become overwhelming. This case study walks through a systematic approach we used for a 45-story residential tower in Miami.

The building had 400 residential units, 4 floors of parking, retail space on the ground floor, a rooftop amenity deck, and numerous mechanical and utility rooms. The client needed clear access separation between residents, staff, retail tenants, and management.

We started by mapping every door that required a lock. This inventory is crucial—missing a single door can compromise the entire system's security logic. We documented 847 cylinders total, including unit doors, common area doors, utility closets, elevator machine rooms, and emergency exits.

Next, we established the access hierarchy. At the top was the Grand Master, held only by the property manager. Below that, we created sub-masters for different functional areas: Residential (all unit doors), Common Areas (lobbies, gyms, pools), Mechanical (HVAC, electrical rooms), and Retail (ground floor commercial spaces).

For the residential floors, we implemented floor masters. The building engineer could carry a single key that opened all mechanical and common area doors, but not individual units. Maintenance staff had keys that opened common areas on their assigned floors only.

One critical decision was how to handle the parking garage. We created a separate sub-system where resident keys opened their assigned parking level but not others. This prevented residents from accessing floors where they didn't belong while still allowing convenient garage access.

The planning phase took three weeks using MCKS. We mapped every cylinder, assigned access levels, and generated documentation showing exactly which keys opened which doors. When the locksmith arrived to install the system, they had a complete blueprint—no guesswork, no site visits to figure things out.

The result was a system that was installed in half the typical time and came in under budget. More importantly, the building management has clear documentation they can reference for years to come when issuing new keys or modifying access.