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“What is a masterkey system?”

A masterkey system is used to regulate the security of different doors. First of all, it involves keeping track of keys that open a door through the use of codes imprinted onto the key. Then, cylinders are pinned in a specific way that allows one key to work many doors, many keys to work one door, or a mixture of the two. The concept is better visualized, as seen below.

“What different types of key system products are available?”

There are 3 types of Key System Products:

1. Unrestricted
   • Advantages: Least Expensive, Easy to get same day keys/rekeys
   • Disadvantages: Keys can be duplicated by anyone anytime. This means even if a
     key is handed in upon employee’s resignation, you will still have to rekey the
     space/suite/building.
2. Restricted
   • Advantages: Keys cannot be copied without ordering from vendor. Rekeying
     space/suite/building not necessary if key is handed in.
   • Disadvantages: More expensive. Cylinders needed may not immediately be in
     stock.
3. Proprietary
   • Advantages: Keys cannot be copied without ordering from vendor. Rekeying
     space/suite/building not necessary if key is handed in. No other vendors can get
     your blanks without permission.
   • Disadvantages: Most Expensive. Cylinders needed may not immediately be in
     stock. Very difficult to switch vendors.

“What typically justifies rekeying an entire building?”

• Fortunately, our most common reason to rekey the whole building is that the master key system has matured. Master Key systems generally are only expected to last 10 years. If you limit the number of keys given out, these systems can largely outlive this life expectancy- but, in many cases, the number of tenants moving in and out of a building will eat the available change keys, resulting in the need for a rekey.
• Another reason a building may be rekeyed is if it changes owners. Some restricted masterkey systems will have multiple buildings on a block- but if one building is sold, the new owner will need to rekey the building on to their own restricted system.
• A worst-case scenario for rekeying a building is when the Great Grand Master Key is lost- either by the building owner or staff. This is the main reason why locksmiths will try to restrict GGMKs to 3 or 4 copies. It is better to hand out a lower-level key (like a floor master) than it is to hand out one with access to the entire building.

“How do you pick the correct necessary size keying systems?”

Often a locksmith will make a recommendation based on the size of your building, but you can see a few examples below:

• A 5-pin Keyway will allow around 1000* Change Keys and is good for small shopping centers and two floor buildings- however, there are fewer restricted keyways with only 5 pins.
• A 6-pin keyway will allow around 3000* Change Keys, and are often used for buildings up to about 15 floors. This is our most common size.
• A 7-pin keyway will allow around 13,000* Change Keys, and are great for properties that have multiple buildings several stories high.
• There are also keying systems with a linear growth in which there is a master keyway that works many different keyways. These can allow upwards of 30,000* Change Keys, and are really useful if you have more than 5 buildings under one Master Key System.

*The number of bittings/individual door keys will vary depending on the GGMK used.

“What are the best practice to manage key systems once you own them?”

• Limit the number of GGMK keys you give out.
• Get keys back from employees that have resigned/been dismissed.
• Store/Secure all keys in a single location, and implement a check in/ check out procedure for temporarily used keys.
• If you have any concerns about a key request or key management, contact your locksmith/vendor promptly.

“How often are the same bitting numbers (key cuts) used in the locksmith world?”

Unfortunately, this question does not have a straight answer. Variables such as number of pins
or restrictions on keyways greatly decrease these chances.

• A small 4-pin desk key’s bittings have probably been used thousands of times. Depending on the key type there can be around 30 to 400* bittings for this key, but those cam locks are used in so many types of drawers and containers, it is impossible to say how many times those bittings get reused.
• Fortunately, this is a huge benefit to a Restricted or Proprietary System. As mentioned, a 6-pin key may have around 3000* different bitting combinations- BUT this doesn’t matter if you are on a different keyway to your neighbor. You may have the same master key bittings as another user; but if you have a different keyway, their key will not fit into your lock.
• There are also several other methods used by companies to ensure that no one will have the same restricted key which we have not discussed:
• Some keyways use angled cuts on the keys. A pin must then be rotated correctly in order to open the lock.
• Some keyways used dimples on the keys. Ball bearings within the lock then must be settles in a dimple in order to open the lock.

In conclusion, if you have questions, don’t be afraid to ask your locksmith or vendor about your concerns. There
is a vast amount of knowledge available, especially when it comes to restricted keyways; and we are happy to
clarify or expound upon this topic.