19/02/2026
Master-Key System design, installation and management is a structured process, ensuring security, integrity and access in an organised and scalable way.
The goal is to let different people open different doors with the minimum number of keys, while maintaining security.
What is Master keying?
Master-keying is a method used in pin tumbler locks to allow multiple different keys to open the same lock, each with different levels of access.
It’s commonly used in places like offices, hotels, schools, and large buildings where individual key holders require different levels of access.
How it works (a simple explanation)
A pin tumbler cylinder can only be turned (opened) when a shear line is created, the shear line being the point where the bottom and top pins align so the cylinder can turn.
A master-keyed pin-tumbler cylinder has additional master pins between the top and bottom pins, allowing for the creation of multiple shear-lines.
The Change-Key aligns the pins at one shear-line.
The Master-Key aligns the pins at another shear-line.
Both keys can turn the lock, but they do so using different pin alignments.
Essentially, the lock is engineered to recognise more than one correct pin pattern.
Why Use Master-Keying?
It allows for structured access control such as:
• A tenant key that only opens one flat or room
• A sub master key that opens all rooms in a department or floor
• A grand master key that opens everything
The Advantages Of Master-Keying
• Cost effective compared with electronic access systems
• Easy to integrate into existing mechanical locks
• Very flexible access hierarchies
for more information, give our office a call on (07)32527872 or email [email protected]
