What Is Maison Keying?
Maison keying is a specific keying arrangement used in multi-unit residential buildings where every tenant's unit key also opens the common entry doors of the building — vestibule, lobby, laundry room, mail room, and similar shared spaces — but does not open any other tenant's unit. The building entry functions as a shared common denominator across all change keys in the system, while each apartment lock remains individually keyed.
The term comes from the French word for “house” and has been a standard residential property keying convention for decades. If you manage or specify hardware for apartment buildings, senior living communities, or mixed-use residential properties, understanding maison keying is essential before the first lock gets ordered.
How Maison Keying Differs From a Standard Master Key System
This distinction matters more than most property managers realize at the outset.
- Standard master key system: A master key opens every lock in the hierarchy. Change keys open only their assigned lock. The master key holder (management, maintenance) has total access.
- Maison keying: There is no single key that opens every unit. Instead, the common-area cylinders are combinated to respond to every tenant change key in the building. The management master key still exists separately and opens everything — but the novelty of maison is that the tenant key itself carries common-area access without elevating the tenant to a master key holder.
In mechanical terms, the common-entry cylinders are cross-keyed to accept all the individual tenant change keys. This requires careful pin tumbler planning at the factory level. It is not something to sort out in the field.
Where Maison Keying Makes Sense
Maison keying is well suited to the following applications:
- Garden-style and mid-rise apartment communities with controlled building entries
- Senior living and independent living facilities where residents carry one key
- Mixed-use buildings where residential tenants share a lobby with retail or office space
- Properties with multiple common amenity doors: fitness room, package room, pool gate, parking structure pedestrian entry
- Any building where management wants to eliminate a separate building-entry key and simplify the tenant key package
It is less appropriate for high-security applications, large campus environments with many building clusters, or anywhere the number of common-area cylinders and unique change keys makes the mechanical cross-keying relationship too complex to hold without sacrificing security.
The Core Hardware: What Gets Specified
Maison keying is a cylinder-level decision, but it touches several hardware categories across the project.
Common Entry Doors
Building entry doors typically carry a heavy-duty mortise lockset or a cylindrical lockset with an exterior cylinder. The cylinder at the building entry must be factory-combinated to accept every change key in the tenant roster. Preferred brands for this application include Corbin Russwin, Sargent, and Hager, all of which offer robust mortise and cylindrical platforms with well-supported keying programs.
In jurisdictions like New York City, local building codes add requirements on top of basic keying: heavy-duty locksets with auxiliary latch bolts, stopwork provisions, and intercom release systems at main entrances. The outside cylinder of the main entry must be operable by the tenant key, but that tenant key must not also open the tenant's apartment door — a direct contradiction of maison keying as typically applied. Know your local jurisdiction before finalizing the keying specification.
Unit Entry Doors
Each apartment door gets its own change key — the same key that opens the common entries under a maison arrangement. Unit doors in residential applications must also meet applicable fire-door hardware requirements if the corridor is a rated assembly. A properly rated cylindrical or mortise lockset with the correct UL listing is required; the keying arrangement does not change the fire-rating obligation.
Amenity and Service Doors
Mail rooms, package lockers, fitness rooms, bike storage, and mechanical chases each represent a decision point: does this door get pulled into the maison cross-key, or is it restricted to management only? Define this scope before the keying schedule is submitted to the factory. Changing it after cylinders are combinated adds cost and lead time.
Interchangeable Core Cylinders: The Smart Choice for Tenant Turnover
Apartment buildings rekey constantly. Every vacancy is a potential security event. Interchangeable core (IC) cylinders address this directly: a control key removes the core and a new pre-keyed core drops in — no locksmith, no lock removal, no downtime on the door.
For a 50-unit building, the math is straightforward. IC rekeying runs a fraction of the cost of conventional cylinder repinning or full lock replacement. Over a five-year management cycle, the savings are substantial. Brands such as Corbin Russwin and Sargent offer SFIC-compatible platforms that allow mixing hardware families while maintaining a single key system — a practical advantage on renovation projects where not every door gets replaced at once.
Common Mistakes in Maison Keying Specifications
- Treating it like a standard master key system: The factory combinating logic is fundamentally different. Submitting a keying schedule that simply says “master key all common doors” will not produce a true maison arrangement.
- Not defining the scope of common areas upfront: Every door added to the cross-key pool after combinating is an exception order. Define the full list before the schedule ships to the factory.
- Overlooking local code requirements: Some jurisdictions impose specific requirements on building entry cylinders — stopwork, auxiliary latching, or intercom integration — that interact with how the cylinder is specified. Coordinate with the authority having jurisdiction early.
- Skipping IC cylinders on high-turnover properties: Conventional cylinders work, but the total cost of ownership over years of tenant changes argues strongly for IC on any property with regular vacancies.
- Ordering too few change keys per unit: A standard allocation is two change keys per tenant plus one retained by management. Budget accordingly when placing the initial order.
Getting the Keying Schedule Right
A complete maison keying schedule submitted to the factory should include:
- Total number of unique change keys (one per unit, sequentially numbered)
- List of all common-area doors to be cross-keyed to all change keys
- List of restricted doors (management-only, maintenance, mechanical) that are not in the maison pool
- Master key quantity and holders
- Control key quantity (IC systems)
- Keyway designation — confirm availability and serviceability in your market
- Stamp or stamping preference (unit number on key bow, do-not-duplicate, etc.)
DoorwaysPlus works with property managers, general contractors, and architects to develop and review keying schedules before the order is placed. Getting the schedule right the first time avoids costly re-combinating and field corrections after installation.
Ready to Spec Maison Keying for Your Property?
Whether you are speccing a new apartment community, retrofitting an existing building, or simply trying to sort out why your current keying arrangement is not working the way it should, DoorwaysPlus carries the cylindrical locksets, mortise locksets, and IC cylinder systems suited to residential and mixed-use keying programs. Contact our team to review your keying schedule or request a quote on the hardware you need.