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Rekeying and Master Keys
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Rekeying, Master Key Systems, and
Key Duplication Services in Roseville, MI

As a business owner, it's your responsibility to manage and monitor who goes in and out of your buildings. If a key falls into the wrong hands, security is compromised.

Key management is an extensive process that can involve hundreds of lock systems throughout your building. Over the last four decades, Great Lakes Security Hardware has helped thousands of organizations re-key their facilities and implement master key systems that keep their properties safe while providing employees access to authorized areas. Our experts can help you plan your access management strategies in great detail and deliver key systems that fit your day-to-day activities and security needs.

The team at Great Lakes Security Hardware is made up of seasoned Roseville locksmiths and door installation experts. Our team has the experience to handle any sized job and develop the correct solution for any building, including large facilities with multiple mixed-use entryways.

We help local business owners stay prepared. With our thorough security inspections, our experts will confirm everything about your building is safe and in line with city, county, and state regulations. Read on below for more information about rekeying and other key services we offer. To receive a free consultation, contact us today!

Contact us today for a FREE CONSULTATION.

Rekeying Service and Master Keys

At Great Lakes Security Hardware, our lock rekeying services begin with a site survey to take every entryway into consideration. At your location, we record notes about the existing doorframe, door locks, and other hardware as well as details like how many cylinders and locking mechanisms each door has.

For rekeying services and locksmiths in Roseville, MI, contact us now.

Key Duplication

Have you recently expanded your workforce and want to have more keyholders, but there aren't enough keys? Maybe you need to keep a spare key for supervisory or emergency access. Whatever your situation may be, Great Lakes Security Hardware can create the duplicate keys required.

Swing by our showroom in Roseville for quick and easy key duplication.

Rekeying, Master Key, & Key Duplication Services in Roseville MI - AdobeStock_53471440

What Is Rekeying?

Rekeying refers to the process of changing the key of a lock while keeping the same lock. The lock is taken apart and some internal parts (such as the key pins and/or tumblers) are replaced. Often, you don't need an entire lock changed.

The reasons for rekeying locks or rekeying a door are numerous: personnel changes, security threats, renovations, etc. But one thing is for sure: if a key gets into the wrong hands, you’ve got a serious safety hazard afoot.

Contact us today for a FREE CONSULTATION.



What Is A Master Key System?

To ensure your building has the level of security you desire, you need a good key system. Below are the names for keys in a typical key system, from least access to most access.

  • Change Key: A change key is sometimes called a "sub-master key." It is intended for use with only one lock or door in your building.
  • Master Key (MK): A master key opens several different locks or doors. In some key systems, this will be the highest-ranking key.
  • Grand Master Key (GMK): A grand master key grants access to multiple master key systems.
  • Great Grand Master Key: A great grand master key will open all the grand master key systems and master key systems under it, as well as the doors with a change key.

When it comes to rekeying, there are multiple "levels" of security. However, contrary to popular belief, more complexity doesn't mean more security.

  • 1-Level System: There is no master key in a 1-level key system. Each door has a unique key, meaning cylinders are operated by individual keys only. This type of keying offers the highest level of security. Examples: Residential homes, small stores.
  • 2-Level System: Features only change keys and master key. Lock cylinders are operated by a change key and a master key. Examples: Elementary schools, apartments, industrial buildings.
  • 3-Level System: Lock cylinders are operated by a change key, a master key, and a grand master key. Examples: Office buildings, large schools, hospitals.
  • 4-Level System: In the most complex system, lock cylinders are operated by a change key, a master key, a grand master key, and a great grand master key. This level of keying offers the least amount of security, since there are many different shear lines for all these different keys to unlock the lock. This opens up the opportunity for keys not meant for that lock to unlock it. Examples: Universities, large government complexes.

When planning your key system, don't overlook your building's core maintenance areas like mechanical rooms, server rooms, stairwells, and enclosed HVAC areas. These spaces can share one key, but they should not have the same key as entrances or offices. This will prevent the need to issue master keys to maintenance personnel.

During a security inspection or consultation, we'll go over some important questions with you. For example, who is authorized to carry the master key? Does every employee receive their own key? Where are spare keys stored?

Get Your Free Quote for Door Rekeying Services in Roseville, MI

For professional rekeying services, put your trust in Great Lakes Security Hardware. It is our goal to help you control access to your space, creating a safe environment for your valued employees and customers. We assist in planning for master key systems for facilities of all kinds, and our comprehensive security inspections pinpoint weaknesses to discourage — and prevent — burglary and other catastrophes. Plus, we provide ongoing technical support for every job we complete!

In addition to rekeying, key duplication, and other locksmith services, Great Lakes Security Hardware also performs the following:

Since 1990, Great Lakes Security Hardware has been a trusted commercial door installation contractor, industrial door supplier, and provider of other door hardware in the Roseville area. Our employees are specialists in the service and installation of commercial doors, locks, security hardware, emergency exit devices, and entry systems. Over the decades, we’ve worked with a number of respected clients including schools, banks, restaurants, police stations, offices, and many others on a variety of projects, all while staying in compliance with Michigan building codes. We invite you to explore our other commercial door products online.

For increased security and peace of mind, call the licensed and insured technicians at Great Lakes Security Hardware. Whether you need help developing complete hardware security solutions for your business or just need a duplicate key cut, we're here for you.

To learn more about rekeying and master key systems, contact us today for a free consultation!

Contact us today for a FREE CONSULTATION.

We Have Provided Exceptional Security Services to
Thousands of Macomb & Oakland County Businesses & Residential Customers
I needed my business door lock cylinder rekeyed as the tumblers had worn out with 20+ years of use. They took care of me while I waited. What great service! I got six new keys and a smooth operating lock cylinder! I am super happy with their service. Need door locks, keys, door parts, pad locks - this is the place to go.'s Rating
I needed my business door lock cylinder rekeyed as the tumblers had worn out with 20+ years of use. They took care of me while I waited. What great service! I got six new keys and a smooth operating lock cylinder! I am super happy with their service. Need door locks, keys, door parts, pad locks - this is the place to go. - David Barker
These guys are awesome. They’ve got some good, knowledgeable people behind the counter and I get excellent service every time. They’ve also come out to service locks for us and we were really happy with that as well. Great prices and I won’t use any one else. Keep up the good work!'s Rating
These guys are awesome. They’ve got some good, knowledgeable people behind the counter and I get excellent service every time. They’ve also come out to service locks for us and we were really happy with that as well. Great prices and I won’t use any one else. Keep up the good work! - April R.