A keyed-alike request solves one access convenience question. A master-key system solves a hierarchy question. A locally supplied cylinder solves an interface and service question. None alone defines security, egress or responsibility.
A hotel package has guest-room doors, service rooms, plant access, common doors and a sales office. The export window-and-door supplier is asked to ‘make all keys the same’. Weeks later, local installers need cylinders compatible with local keys, management wants a hierarchy, an egress consultant raises life-safety questions, and nobody knows who may reproduce master keys. The error was not choosing the wrong key. It was treating lock selection, cylinder interface, key hierarchy, access authority, egress and local service as one informal instruction. This article gives a project-control framework before procurement and at handover; it does not design a security system or interpret any destination law.
1. Separate the five decisions hidden inside ‘keyed alike’
A locking plan starts by separating access convenience from the other decisions. Keyed alike means identified cylinders accept the same change key. A master-key system creates a controlled hierarchy in which different keys can open defined sets of cylinders. A local-cylinder route may retain the imported door and lock preparation while using cylinders/keying supplied and managed locally. Electronic access, key control, emergency egress and security resistance are additional decisions—not automatic results of any mechanical keying label.
BHMA’s A156.28 recommended practices for mechanical keying systems are aimed at owners and security professionals who design, implement and maintain keying systems. Its public summary highlights a keying conference, key management and the ability to extend a system over time. This is useful evidence that keying is a managed system rather than a factory line item. BHMA’s cylinder standard also notes that laboratory tests occur under laboratory conditions and actual use varies with installation, maintenance and environmental conditions.
For every door group, state the role first: public entry, guest room, service, plant, administration, escape route, temporary construction access or another approved role. Then record who enters, under what authority, whether the door is normally locked, how emergency operation is handled by the project route, and who owns later key issue/revocation. Do not share a master-key chart in general tender emails; it is controlled security information.
| Decision | Question to close | Evidence owner | Do not assume |
|---|---|---|---|
| Keyed alike | Which named cylinders may accept the same authorised key? | Controlled door/key schedule | That all doors should share access |
| Master keying | Which authorised hierarchy and future expansion are required? | Owner/security professional keying plan | That a supplier can infer roles from room names |
| Local cylinder | What cylinder format/interface and local service route are approved? | Door/hardware schedule plus local specialist | That every cylinder fits every imported lock preparation |
| Egress/fire | Which doors have separate life-safety operation requirements? | Destination code/professional review | That a locking convenience choice satisfies egress |
| Security/key control | Who may issue, reproduce, revoke and audit credentials? | Authorised owner/security process | That a cylinder test equals a complete security system |
2. Build a door-and-cylinder schedule before keying is cut
The controlled schedule should be based on opening marks, not on verbal groups such as ‘all bedrooms’. Record door location and function, leaf/handing, lock and cylinder preparation, current hardware revision, intended lock function, user group, desired keying relationship, egress/fire/accessibility review status, local-cylinder option, spare/replacement route and authority for each decision. The schedule is not a key-bitting chart; keep sensitive keying data under restricted access and show only the identifiers needed for coordination.
Identify all interfaces before ordering. Cylinder shape, length, cam or tailpiece, lock case, handle/escutcheon, door thickness and lock function can be system-specific. A product photograph or a phrase such as ‘Euro cylinder’ or ‘standard key’ is not adequate project evidence. Ask the named hardware manufacturer or responsible local specialist to confirm the exact approved interface against the complete door configuration.
Use a change-control rule. A revised door thickness, trim, lock case, electronic access option, finish, local cylinder or egress function can change the locking package. Freeze affected lines, record the technical and commercial impact, and issue an authorised revised schedule. Do not let cylinder substitution occur at installation because a local distributor has stock.
| Record | Required entry | Review question |
|---|---|---|
| Opening identity | Door mark, location, function and current drawing revision | Does this record match the installed door? |
| Lock/cylinder interface | Exact lock body, cylinder preparation, trim and relevant dimensions from approved documents | Has compatibility been confirmed for the complete assembly? |
| Access role | Authorised user group and keying relationship identifier | Is access convenience being confused with security authority? |
| Life-safety review | Destination/project reviewer and status | Is a separate egress/fire/accessibility decision still open? |
| Local service | Approved source, replacement and emergency service contact | Can the owner actually maintain the system locally? |
| Change record | Old/new item, affected openings, approver and date | Has an informal site substitution been prevented? |
3. Treat keys and key data as controlled assets
A hierarchy can fail through uncontrolled issue, copying, loss, temporary access or weak handover even when every cylinder is genuine. Establish an owner-side key-control procedure before delivery: authorised issuer; named recipients; handover identity check; record of issue/return/loss; treatment of construction keys and temporary access; storage; incident escalation; and decision authority for rekeying or replacement. Keep physical keys, codes, charts and digital access data out of ordinary shipment correspondence and general photo records.
BHMA A156.28’s focus on key-management practices supports this governance approach, but it does not write a project’s security policy. The project must decide privacy, staffing, emergency access, local law and insurance requirements. A factory or exporter should not retain an unapproved master key, distribute duplicate keys or claim post-handover control unless the contract and owner’s security process explicitly authorise it.
At handover, reconcile what was ordered, what was supplied and what was issued. Record sealed package identifiers rather than key codes in broadly shared documents. If loss or compromise is reported, preserve the event record and route the response to the authorised security decision-maker; do not promise that changing one cylinder resolves a hierarchy-wide risk.
| Stage | Controlled record | Authority | Boundary |
|---|---|---|---|
| Design release | Approved door/keying identifiers and restricted-data owner | Owner/security authority | Not a public bitting schedule |
| Production/packing | Package identities and delivery custody | Authorised supplier/owner contact | Not proof of access authorisation |
| Issue | Recipient, date, identity check and asset status | Named key issuer | Not a transfer of master-key design authority |
| Return/loss | Event, keys affected and escalation | Security authority | Not an automatic rekey instruction |
| Replacement | Approved component/source and revised register | Authorised project process | Not a visually similar local substitute |
4. Release only after local interfaces and special doors are resolved
Before release, reconcile the hardware schedule, door configuration, cylinder interface, keying relationship identifiers, local service route, egress/fire/accessibility holds and handover custody plan. Mark lines as ‘approved for the stated locking scope’, ‘difference awaiting authorised review’ or ‘not released’. That is more useful than saying a package is ‘master-key ready’ when important doors or cylinder interfaces remain unconfirmed.
This article deliberately does not state which doors must be free egress, which locks are permitted, how master levels should be structured, or what security performance is adequate. Those conclusions depend on destination regulations, use, fire strategy, access policy and qualified professional design. The commercial scope should identify who supplies and installs the physical components, who owns keying decisions, and who is responsible for the final legal and operational approval.
FAQ
Is keyed alike the same as a master-key system?
No. Keyed alike is a shared-key relationship among identified cylinders. A master-key system is a controlled hierarchy with broader governance and key-control requirements.
Can local cylinders be selected after imported doors arrive?
Only through an approved compatibility and change-control route. Cylinder interface, lock function, trim, door configuration and local rules must be checked.
Does a cylinder laboratory test prove whole-door security?
No. BHMA notes laboratory conditions and its material distinguishes component standards. Door, frame, installation, access control and project threats remain separate questions.
Can a master key chart be sent with all shipping documents?
Avoid broad distribution. Treat keying data as controlled security information and use the owner’s approved custody process.
Does a locking plan decide egress requirements?
No. Egress and fire requirements depend on destination regulations and approved professional design; do not infer them from a keying label.
Continue the project review
Connect this guide with the proposed window and door systems, then review how Cavorlen approaches manufacturing and quality control. When your schedule is ready, send it through the project review form.
Official sources used
BHMA A156.28-2023 — recommended practices for mechanical keying systems ↗BHMA A156.5 — cylinders and input devices for locks ↗BHMA — lock and keying standards overview ↗ICC — international sale model-contract scope ↗Related buyer guides
This guide does not select lock functions, cylinders, keyways, master-key hierarchy, security grade, egress hardware, electronic access system, local code path or installation detail. It does not determine legal responsibility, fire/egress compliance, burglary resistance, key-copy rights or insurance acceptability. Destination regulations, the responsible security/fire/accessibility professionals, approved door schedules, hardware manufacturer documents and the signed contract govern the actual solution.