When deciding to create a master keying system, whether for padlocks or door cylinders (or both in combination), it is essential to draw up a document – called a lock plan – to define which keys will open exactly which doors. In other words, this document will define the master keys, sub-master keys and independent keys in the entire master keying system for a building or part of a building.

Purpose of a lock plan
• To define the key access levels.
• To serve as a guide when producing the keys and deciding on the internal configuration of the cylinders and/or padlocks.
• To create a master keying history log, which will be essential for any future expansions.

Who creates the lock plans?
First of all, it should be pointed out that lock plans are more often than not produced by the cylinder and padlock manufacturer. This provides the clearly necessary level of security for users of the master keying system by preventing unauthorised access to the plan by third parties. This preventive measure is also aimed at control and consistency in the development of the system over time.

The master keying system may also be produced by a centre authorised by the manufacturer. However, this will always take place under supervision by the brand, which will always have a copy of the lock plan.

How to read a lock plan?
Interpreting a lock plan is very simple. The most common model is very similar to a spreadsheet table. At IFAM, our lock plans look like this:
– The keys that comprise the master keying system are shown in the rows of the table. They normally indicate the code etched into the key once the master keying system manufacture order is issued. They also include a name to facilitate identification, which usually matches the type of door or access level they open.
– The cylinders or padlocks are shown in the columns of the table. The upper cells in the columns contain cylinder or padlock models included in the master keying system and the door or access where they will be installed.
– The cells where the rows and columns intersect, indicate which key opens a certain cylinder or padlock. This shows which are the master keys, the sub-master keys and the independent keys for the whole system.

The next step
Once the lock plan has been produced and with the help of some specialised software, the algorithmic calculations are performed to determine key manufacture and the pin layouts for the cylinders and padlocks.

In a future post, we will tell you how the elements comprising a master keying system are manufactured.