Rekeying a lock is the process of altering the lock’s internal mechanism so that it will operate with a completely new key, while the existing exterior lock hardware remains in place. This procedure effectively renders all previous keys for that lock useless, which is a significant factor in maintaining security. It serves as an efficient and cost-effective method to update access control to a property without the need to purchase and install an entirely new lockset.
The Internal Mechanism
The rekeying process centers on the lock’s cylinder, which contains a series of small components known as pin stacks and a shear line. Each pin stack consists of two parts: a key pin on the bottom and a driver pin on top, separated by a distinct line called the shear line. When the correct key is inserted, its unique cuts, or bitting, precisely lift the key pins and driver pins so that the shear line aligns perfectly with the edge of the cylinder. This alignment creates a straight, smooth path that allows the cylinder to rotate and unlock the door.
To rekey a lock, a professional carefully disassembles the cylinder and removes the existing key pins. These are then replaced with a new set of key pins that correspond exactly to the pattern of the new key you wish to use. The new key pins are of different sizes and are arranged to align the shear line when the new key is inserted, instantly invalidating the old key’s ability to turn the cylinder.
Practical Reasons to Rekey
Homeowners often choose to rekey their locks for a number of common reasons focused on security and convenience. Moving into a new residence is a prime example, as there is no reliable way to confirm how many copies of the original keys are still circulating among previous owners, tenants, or contractors. Rekeying provides peace of mind by ensuring that only the current occupants have authorized access to the property.
Another frequent scenario is the loss or theft of a key, which immediately compromises the security of the property until the lock is altered. For rental property managers, rekeying is a standard procedure between tenant turnovers to maintain control over access. Additionally, rekeying allows for the practical consolidation of keys, meaning multiple locks on a home, such as the front door and the back door, can be adjusted to operate with a single key.
Rekeying Versus Replacing
The choice between rekeying and completely replacing a lock depends primarily on the lock’s current condition and the homeowner’s security goals. Rekeying is significantly more affordable and faster, typically requiring only the cost of labor and a handful of small internal parts. A professional locksmith can often complete a rekeying service for multiple locks in a single visit, making it an efficient solution when the existing lock hardware is functional and aesthetically pleasing.
However, if the current lock is visibly damaged, heavily worn, or malfunctioning, a full replacement of the entire lockset is necessary. Replacement is also the required course of action when a homeowner wants to upgrade the security level of their door, such as moving from a basic lock to a high-security model with advanced features. Furthermore, a total replacement is needed to install modern hardware like smart locks or electronic keypads, which are fundamentally different from traditional mechanical locks.
Replacing a lock is a more time-consuming and expensive undertaking, as it involves the purchase and installation of new hardware components. While DIY rekeying kits exist, they require a specific understanding of the internal mechanism. Rekeying is the logical choice for updating security when the hardware is sound, while replacement is reserved for necessary repairs or security upgrades.