Master Key Systems

Master key systems, when implemented by the wrong company, can be extremely complex, confusing and frustrating. For example, we recently worked on a church in Cartersville, and I could kind of see the early signs of what I call the master key system haze. Confusion had set in. But most importantly she had at least figured out what employees were going to be given access to what areas at the church. Which is extremely untypical by the way.

Master keyed lock setup

Master key setup is the most crucial part of a Master key system. You have to build in a lot of forethought and anticipate growth. It’s pretty easy to simplify most systems. Master systems control who will have access to where. And then you have to remember but you can only really have so many sheer lines in one lock, and one shear line equals one key. If you add four Shearlines you have added for keys. It’s important to remember that every key that you add the less secure the lock becomes so as a result, I don’t typically like to go beyond 4 keys per lock. This is an example of a simplified Master key system.

Complex Master system diagram
A diagram of a fairly complex master key system.
Simplified master system
A small system where one key will operate all doors and then another key will fit two doors and the master and then lastly the other three doors operate with just the master key and their individual keys.

Are Master keyed locks less secure?

In short, yes. The more complex you make a master system the more shear lines you add. The more shear lines that are present consequently the more likely the lock can be picked. How much less secure does it make your locks to have the master keyed? With a simple Master keyed lock not very.