Replace a front door lock.

In the UK, the type of lock you need depends heavily on your door material. Timber doors usually require mortice locks or night latches, while uPVC and composite doors rely on multipoint locking systems and euro cylinders. Choosing the right hardware is essential not just for security, but for complying with your home insurance policy.

What Does the Work Involve?

• Security Assessment: The locksmith inspects the door material, current lock type, and frame condition to recommend the most secure replacement.
• Old Lock Removal: Careful extraction of the existing cylinder, mortice box, or multipoint gearbox without damaging the door leaf.
• Component Matching: Sourcing a replacement that matches the existing apertures to avoid unnecessary drilling or "botched" patches.
• Installation and Alignment: Fitting the new hardware and adjusting the strike plates or keeps to ensure the door closes and locks smoothly.
• Testing: Verifying the lock operates perfectly from both sides and ensuring the key turns without resistance.
• Waste Disposal: Removing old metal components for recycling and providing a set of new, sealed keys.

Typical Costs

Prices vary based on the complexity of the lock and whether you require an emergency out-of-hours visit. High-security "3-star" cylinders and British Standard mortice locks carry a premium but are often required by insurers.

Factors affecting the final price include your location (London rates are typically 20-30% higher), the brand of hardware chosen (e.g., Yale, ERA, or Brisant Ultion), and whether the door frame requires repair work.

How Long Does It Take?

• Standard Euro Cylinder Swap: 20–40 minutes. A straightforward job if the door is already aligned.
• Mortice Lock Installation: 45–90 minutes. Requires manual chiselling of timber doors.
• Multipoint Mechanism Replacement: 1–2 hours. Involves removing the entire strip from the side of a uPVC or composite door.
• Fresh Fit (New Hole): 1.5–2.5 hours. Installing a lock where one didn't exist before requires precision cutting and drilling.

DIY or Professional?

While swapping a basic euro cylinder is a common DIY task, it is fraught with risks. If you measure the cylinder incorrectly and it protrudes more than 3mm from the handle, it is vulnerable to "lock snapping"—a technique used in the majority of UK burglaries.

For mortice locks and multipoint systems, professional installation is highly recommended. Incorrect DIY fitting can void your home insurance if a break-in occurs. A professional locksmith ensures the hardware meets British Standard BS3621, which is a mandatory requirement for many UK insurers.

Choosing the Right Tradesperson

• Check Qualifications: Look for locksmiths vetted by the Master Locksmiths Association (MLA).
• Verify Insurance: Ensure they hold public liability insurance (minimum £1m–£2m).
• Request a Quote: Ask for a total price including VAT and parts before they start work.
• DBS Check: Since they are handling your home security, ask if they have a clear, recent DBS check.

Always ask the locksmith if the hardware they are installing is "insurance approved" and meets the current British Standards.

UK Regulations

• BS3621: The standard for thief-resistant locks on timber doors. Look for the Kitemark symbol on the faceplate.
• TS007 3-Star: The highest security rating for cylinders on uPVC and composite doors.
• Fire Safety (Part B): For flats or HMOs, front door locks must often be "keyless egress" (e.g., a thumb-turn) to allow exit without a key in an emergency.
• Minimum Standards: Most UK insurers specify that all ground floor exits must have a 5-lever mortice deadlock or a multi-point locking system.

Common Problems

• Door Dropping: If the door has sagged, the lock won't line up with the strike plate. Forcing the key in this scenario will eventually snap the internal mechanism.
• Lock Snapping: Cheap, standard cylinders can be snapped in seconds. Always upgrade to an "Anti-Snap" 3-star cylinder for uPVC doors.
• Incorrect Measurements: Buying a lock that is too long or too short for the door thickness leads to security vulnerabilities and poor aesthetics.
• Cheap Imports: Non-branded locks often lack the internal hardened steel pins required to resist drilling.

Frequently Asked Questions