The Complete Guide to Rekeying a Lock: DIY Home Security

How To Rekey a Lock: A Comprehensive Guide

Rekeying a lock is an essential skill for homeowners looking to enhance their property’s security without the expense of complete lock replacement. This process involves changing a lock’s internal mechanism so it operates with a new key, rendering old keys useless. Whether you’ve recently moved into a new home, lost your keys, or simply want to upgrade your home’s security, rekeying offers a cost-effective solution that gives you peace of mind.

Unlike replacing entire locks, rekeying preserves your existing hardware while changing only the internal components that determine which key will operate the lock. This guide will walk you through the entire process, from understanding how locks work to completing a successful rekeying project.

Understanding Lock Rekeying

When you rekey a lock, you’re essentially reconfiguring the internal pin tumblers that match a specific key pattern. Most residential locks use a pin tumbler mechanism, which consists of several spring-loaded pins of different lengths. When the correct key is inserted, these pins align perfectly at what’s called the shear line, allowing the lock cylinder to turn and operate the locking mechanism.

Rekeying changes the configuration of these pins so that only a new key with the corresponding cuts will align them properly. The old key will no longer work because the pin heights no longer match its cut pattern. This process doesn’t affect the security level of your lock but rather changes who has access to your home.

Benefits of Rekeying Your Locks

There are several advantages to rekeying rather than replacing your locks:

• Cost-effectiveness: Rekeying typically costs a fraction of what new locks would cost, especially if you do it yourself.
• Convenience: With proper tools and instructions, rekeying can be completed in about 30 minutes per lock.
• Key control: You can rekey multiple locks to work with the same key, reducing the number of keys you need to carry.
• Security: Rekeying invalidates all existing keys, ensuring that previous homeowners, contractors, or anyone who had access can no longer enter your home.

When to Rekey Your Locks

Several situations warrant lock rekeying:

• Moving into a new home: Previous owners, real estate agents, and contractors may have copies of your keys.
• After a break-in: If your home has been compromised, rekeying helps restore security.
• Lost or stolen keys: When keys go missing, rekeying prevents unauthorized access.
• Key consolidation: If you’re tired of carrying multiple keys, rekeying allows you to operate all locks with a single key.
• Tenant turnover: Landlords often rekey between tenants to ensure security.

Tools and Materials Needed for Rekeying a Lock

Before beginning the rekeying process, gather all necessary tools and materials. Having everything at hand will make the process smoother and help prevent mistakes.

• Rekeying kit: Specific to your lock brand (Kwikset, Schlage, etc.)
• Current working key: You’ll need this to remove the cylinder
• New keys: Either pre-cut or to be cut based on the new pin configuration
• Flathead screwdriver: For removing the lock from the door
• Phillips screwdriver: For disassembling the lock
• Needle-nose pliers: For handling small pins and springs
• Key gauge: For determining proper pin sizes (usually included in rekeying kits)
• Plug follower: A cylindrical tool that holds the springs in place (included in most kits)

A standard rekeying kit typically includes new pins, springs, a plug follower tool, and sometimes a key gauge. Make sure to purchase a kit that matches your lock’s brand and model, as pin sizes and configurations vary between manufacturers.

Step-by-Step Process for Rekeying a Lock

Rekeying a lock involves several precise steps. Follow this guide carefully to ensure success.

Step 1: Remove the Lock from the Door

Begin by removing the lock from your door. For most residential doors:

• Locate the mounting screws on the interior side of the door.
• Use a screwdriver to remove these screws.
• Pull apart the exterior and interior knobs or handles.
• Remove any additional hardware that may be securing the lock to the door.

Step 2: Remove Lock Cylinder

Once you’ve removed the lockset from the door:

• Locate the cylinder retainer, which is typically a small clip or retaining ring.
• Use a screwdriver or the specialized tool from your rekeying kit to remove this retainer.
• Carefully slide the cylinder out of the lock housing.

Step 3: Disassemble Lock Cylinder

This step requires precision and care to avoid losing small components:

• Insert the current key into the cylinder and turn it to align the pins at the shear line.
• Insert the plug follower tool against the back of the cylinder plug.
• While maintaining pressure on the plug follower, push the cylinder plug out of the housing.
• Move slowly and carefully, as this step keeps the upper pins and springs contained in the cylinder housing.

Step 4: Remove Old Pins

With the cylinder plug removed:

• Keep the current key inserted in the plug to hold the lower pins in place.
• Carefully turn the plug upside down and remove the key slowly.
• As you remove the key, the lower pins will fall out of their chambers.
• Collect these pins and set them aside (though you won’t need them for reassembly).

Step 5: Determine New Pin Sizes

To fit your new key:

• Insert the new key into the empty cylinder plug.
• Use the key gauge from your rekeying kit to determine the correct pin sizes for each key cut.
• For each chamber position, select the corresponding pin from your kit that matches the depth indicated by the key gauge.

Step 6: Install New Pins

Now it’s time to reconfigure the lock with your new key pattern:

• Insert your new key into the cylinder plug.
• Drop the appropriate pins into each chamber, starting from the back.
• Ensure each pin sits flush with the top of the plug when the key is inserted.
• Double-check that you’ve installed the correct pins in the correct order.

Step 7: Reassemble the Lock

Put everything back together with care:

• With the new key still in the plug, align the plug with the cylinder housing.
• Use the plug follower to guide the plug back into the housing, pushing the follower out as the plug enters.
• This process ensures the upper pins and springs remain properly positioned.
• Once the plug is fully inserted, remove the plug follower.

Step 8: Test and Reinstall

Before reinstalling the lock in your door:

• Test the new key to ensure it turns smoothly in the cylinder.
• Verify that the old key no longer works.
• Reattach any retaining clips or rings to secure the cylinder in the lock housing.
• Reassemble the complete lockset and reinstall it on your door.
• Test the operation several times to confirm everything works properly.

Rekeying Special Lock Types

Kwikset SmartKey Locks

Kwikset SmartKey locks are designed specifically for easy rekeying without disassembly. The process is much simpler:

1. Insert the current working key and turn it 90 degrees clockwise.
2. Insert the SmartKey tool into the small hole on the face of the lock.
3. Remove the SmartKey tool and then the current key.
4. Insert the new key fully and rotate it 180 degrees counterclockwise to complete the rekeying.
5. Test both keys to confirm the change.

Deadbolt Locks

Deadbolts follow essentially the same rekeying process as doorknobs, with minor differences:

• Ensure the bolt is extended before removing the lock from the door.
• Remove the interior thumb-turn assembly by unscrewing the mounting screws.
• The cylinder can then be accessed and rekeyed following the standard process.

When to Call a Professional

While rekeying is a manageable DIY project, certain situations call for professional assistance:

• High-security locks: Specialized locks often have additional security features that make DIY rekeying difficult or impossible.
• Electronic or smart locks: These typically require professional programming in addition to mechanical rekeying.
• Antique or unusual locks: Vintage hardware may have non-standard mechanisms that require expertise.
• No working key: Without the current key, the lock must be picked open first, which requires specialized skills.
• Multiple locks: If you have many locks to rekey, a locksmith may be more efficient and cost-effective.

Cost Comparison: DIY vs. Professional Rekeying

Understanding the cost difference can help you decide whether to tackle this project yourself:

• DIY rekeying: A standard rekeying kit costs between $12-$25, depending on the brand and quality. This kit can typically rekey 5-6 locks of the same brand.
• Professional rekeying: A locksmith typically charges $40-$100 per lock, with potential service call fees of $50-$100.
• New locks: Replacing locks entirely costs $20-$200 per lock (depending on quality), plus installation if you hire a professional.

For a typical home with 3-5 locks, DIY rekeying could save $100-$400 compared to hiring a professional.

Frequently Asked Questions (FAQs)

Q: Can I rekey a lock without the original key?

A: It’s possible but more difficult. Without the original key, you’ll need to pick the lock open or remove it entirely and disassemble it, which requires additional tools and skills. In most cases, it’s easier to call a locksmith if you don’t have the original key.

Q: Can I rekey different brands of locks to use the same key?

A: Generally, no. Different lock manufacturers use different key and pin systems that aren’t compatible with each other. However, if all your locks are from the same manufacturer, they can typically be keyed alike.

Q: How often should locks be rekeyed?

A: There’s no set schedule for rekeying locks. Instead, rekey when circumstances change, such as moving into a new home, after losing keys, or when you want to revoke someone’s access to your property.

Q: Will rekeying make my locks more secure?

A: Rekeying doesn’t inherently change the security level of your locks. It simply changes who has access. If you want improved security, consider upgrading to higher-security lock models.

Q: Can electronic or smart locks be rekeyed?

A: Most electronic and smart locks still have a mechanical cylinder for backup key access, which can be rekeyed. However, the electronic access codes or credentials are typically changed through programming rather than mechanical rekeying.

Maintenance Tips for Longer Lock Life

After rekeying your locks, these maintenance practices will help extend their lifespan:

• Lubrication: Apply a graphite-based lubricant annually to keep the mechanism moving smoothly.
• Cleaning: Remove dirt and debris from the keyway using compressed air.
• Avoid excessive force: Never force a key that doesn’t turn easily, as this can damage pins.
• Weather protection: For exterior locks, ensure they’re protected from direct exposure to rain and extreme elements.

By understanding the rekeying process and following these detailed steps, you can effectively manage your home’s security without the expense of replacing entire locksets. This DIY skill not only saves money but also gives you greater control over who has access to your home.

Author

Srija Burman

 

Srija holds an MA in English Literature from the University of Calcutta and a PG diploma in Editing and Publishing from Jadavpur University. Her interest in writing and editing ranges across niches, including academics, sports, and human psychology.

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