Mortice Locks & Yale Nightlatches
Two lock types dominate the front doors of Eltham homes: the Yale-type nightlatch that lets you pull the door shut behind you, and the 5-lever mortice deadlock that your insurer almost certainly asks about by name. Whether you live on a Victorian terrace off Well Hall Road, in a purpose-built flat near Eltham High Street, or in one of the newer builds around the SE9 postcode district, the combination of these two locks is still the benchmark for a properly secured front door — and when either one fails, is damaged, or needs upgrading to meet BS3621, that is where our team comes in.
Open 24 hours, 7 days a week · Fully insured
Eltham Locksmith is a fully insured, mobile locksmith service operating 24 hours a day, seven days a week, including evenings, weekends and bank holidays. Our trained technicians come to you — there is no workshop to visit and no waiting days for an appointment. We carry a comprehensive stock of parts in the van, so the large majority of mortice deadlock and Yale nightlatch jobs are completed on the same visit, with an exact, up-front quote agreed before any work begins.
What we do
Available 24/7
Day, night, weekends and bank holidays — a real local locksmith answers and sends a fully-stocked van.
We come straight away
Based in Eltham, we send a locksmith straight away — we're usually with you in about 30 minutes.
Fully insured
Vetted locksmiths, a clear price on the phone, and no surprise add-ons when we arrive.
Damage-free entry
We pick and bypass locks the right way, so most lockouts are solved without drilling anything.
Why Mortice Locks and Yale Nightlatches Work Best Together
A Yale-type nightlatch — the spring-loaded latch that snaps shut when you close the door — is convenient but on its own offers limited security. The bolt can sometimes be slipped with a card or thin tool, and the fixing screws are exposed on the edge of the door. A 5-lever mortice deadlock fitted below it changes the picture entirely. The bolt throws deep into the door frame, the levers must align precisely before it will move, and a British Standard BS3621 version adds anti-pick, anti-drill and anti-saw features that most household insurance policies treat as a minimum requirement. If your policy mentions BS3621 and you do not have one fitted, you could find a claim refused after a break-in — something we see the consequences of fairly regularly in this part of south-east London.
The two locks complement each other because they address different threats. The nightlatch handles day-to-day convenience; the mortice deadlock provides the structural resistance that matters when a door is under real attack. Fitting or replacing either type correctly — with the right backset, case size and forend to suit your door thickness and frame — is a skilled job. A poorly fitted mortice lock with a loose box strike or an incorrectly centred keyhole can be almost as easy to defeat as no lock at all.
Fitting and Replacing 5-Lever Mortice Deadlocks — BS3621 for Insurance Compliance
When one of our technicians assesses a mortice deadlock job, the first thing they check is whether the existing mortice pocket in the door is the right size for the replacement lock case. Timber doors in Eltham's older housing stock vary considerably — some have thick solid hardwood stiles, others have thinner stiles that limit which lock cases will fit safely without weakening the door. We measure the stile width, the existing case dimensions, the distance from the door edge to the centre of the keyhole (the backset), and the condition of the box strike in the frame before recommending a lock. Where a BS3621 upgrade is needed for insurance purposes, we fit a certified 5-lever deadlock and ensure the box strike is recessed and secured with the correct fixings, because a strong lock with a flimsy strike plate offers very little real protection.
If the door has been forced previously — something that does happen on residential streets in this area — the frame around the mortice pocket sometimes needs reinforcing before the new lock is fitted. We carry frame repair kits in the van for exactly this reason. Our aim throughout is to work damage-free where possible: we do not simply attack a seized or jammed mortice lock with a drill unless every other option has been exhausted. When drilling is unavoidable, we keep it precise and confined to the minimum needed, leaving the door and frame in the best possible condition for the replacement fitting.
Yale Nightlatch Replacement — Emergency Locksmith London Calls and Planned Upgrades
Yale-type nightlatches fail in several ways: the latch mechanism wears and stops springing back, the cylinder develops play and the key turns without fully engaging, or the mounting rim becomes loose and the screwfitting pulls away from the door. In a lockout situation — which is the most common reason people ring us at short notice — the latch has often jammed in the locked position or the key has broken in the cylinder. As a 24 hour locksmith London residents can reach at any time of day, we respond to these calls throughout the SE9, SE12 and surrounding postcode districts and are usually with you in about 30 minutes of calling 020 3757 5833.
Replacement nightlatches come in standard rim sizes, but the choice of cylinder quality matters enormously. A basic cylinder can be drilled out in seconds with widely available tools; a cylinder with anti-drill pins, anti-pick serrations and a hardened steel anti-snap line takes significantly longer and may deter a burglar entirely. We discuss these options with you plainly and without pressure, explaining what each level of cylinder offers so you can make an informed decision. For landlords and letting agents managing properties in the Eltham area, we can also change the cylinder in an existing nightlatch case without replacing the whole unit — a straightforward way to withdraw access after a tenancy ends.
Lock Change London — What Determines Your Quote
Residents sometimes ask why a lock change London quote cannot simply be given as a flat rate online. The honest answer is that the variables genuinely affect what is involved in the job. The type and condition of the existing lock, whether the door is timber, uPVC or composite, the time of day (our technicians work through the night and on bank holidays, and that is reflected in the pricing), the distance within our service area, and whether replacement parts need to be sourced from van stock or ordered all play a part. What we commit to without exception is that your exact price is confirmed over the phone before anyone leaves to attend — there are no surprises on the doorstep. If you are a tenant, we will also talk you through what your landlord or letting agent may need to know before we proceed, since changing a lock on a rented property without the right permission can create complications. Call 020 3757 5833 and one of our team will walk you through the options and confirm the quote straight away — we answer 24 hours a day, every day of the year.
Frequently asked questions
Does my home insurance really require a BS3621 mortice deadlock?
Many standard household policies in the UK do specify that external doors must be fitted with a 5-lever mortice deadlock to BS3621 as a condition of cover. The exact wording varies between insurers, so it is worth checking your policy documents carefully. If yours does include that requirement and you currently have only a Yale nightlatch or an older 2-lever mortice lock, upgrading is straightforward — we can supply and fit a compliant BS3621 lock and confirm the British Standard kite mark is on the lock case so you have clear evidence for your insurer.
My front door has a Yale nightlatch but no mortice lock at all — can you fit one on the same visit?
Yes, in most cases. Fitting a mortice deadlock into a door that has never had one requires cutting a new mortice pocket, which our technicians carry the tools to do on site. We will check the stile width of your door first to confirm it can accommodate a full lock case safely. For timber doors of the type common in Eltham's older terraced and semi-detached housing, this is usually very achievable in a single visit. We will also fit the box strike into the frame at the same time and test the full throw of the bolt before we leave.
I have locked myself out — what should I do before I call a locksmith?
Before calling us, it is worth quickly checking whether any other entrance to the property is accessible — a back door through the garden, for instance — and whether a trusted neighbour, family member or your letting agent holds a spare key. If neither of those options is available and you have confirmed the property is yours, ring 020 3757 5833 and we will send a technician straight away. Please do not attempt to force entry yourself, as this can cause costly damage to the door or frame and may also raise concerns with neighbours. We will ask you to confirm ownership or tenancy when we arrive, which is standard practice.
How is the price for a mortice lock or nightlatch job worked out?
The final quote depends on a number of factors: the type of lock being fitted or replaced, whether any repair work to the door or frame is needed, the time of day (evening, overnight and bank holiday calls involve different costs), and the parts required. We confirm the exact price with you on the phone before we come out, so there is nothing unexpected when the job is done. We do not quote vague ranges and then add charges on arrival.
Can you replace just the cylinder in my Yale nightlatch without changing the whole lock?
Yes. In many cases the rim case — the body of the nightlatch that is screwed to the door — is perfectly sound, and only the cylinder needs changing. This is a quicker job and is a practical option when, for example, a tenancy has ended and you want to withdraw access, or when only the cylinder has worn or been damaged. We carry a range of cylinder grades in the van, including higher-security options with anti-snap and anti-pick features, and we will explain the differences so you can choose what suits your door and your circumstances.
Do you work in the evenings, at weekends and on bank holidays in Eltham?
Yes — we operate 24 hours a day, seven days a week, including weekends and bank holidays. There is no time of day or day of the year when we are not taking calls. If you are dealing with a lock problem late at night on a bank holiday weekend, ring 020 3757 5833 and we will arrange for a technician to come to you. We will confirm the exact quote for that time of day before anyone sets off, so you know what to expect.