Mortice Locks & Yale Nightlatches

These four terms are often used interchangeably, but they mean different things and lead to different costs. A lock replacement means removing the existing lock body entirely and fitting a new one — this is typically needed when a mortice deadlock case or a nightlatch rim lock is damaged beyond service, corroded, or simply obsolete. A new installation is what happens when a lock position is being added to a door that did not previously have one — for example, adding a second mortice deadlock higher up the door to satisfy a home insurance requirement. A lock change, by contrast, means swapping out only the cylinder or the follower so that old keys no longer work — commonly requested after a tenancy ends, a break-in, or a lost key. A repair covers adjustments to a sticking bolt, a misaligned striker plate, or a loose nightlatch mechanism that still has serviceable life left in it.

Understanding which category your situation falls into helps you give our team the right information when you call, and means we can bring the correct parts first time. The factors that shape your final quote include the type and grade of lock involved, any parts that need sourcing, the time of day — including evenings, weekends, and bank holidays — and travel distance to your address. We confirm that figure on the phone before anyone sets off, so there are no surprises on the doorstep.

A 5-lever mortice deadlock sits inside the door itself, with the bolt passing through the door edge into a keep fitted to the frame. The BS3621 standard — which many home insurers across the DA6 and DA7 areas now specify as a minimum — sets requirements for bolt throw, anti-pick levers, anti-drill hardened inserts, and overall resistance to manipulation. If your policy mentions BS3621 and your existing lock does not carry that kite-mark, our team can supply and fit a compliant replacement, usually within the same visit. We work damage-free where the door condition allows, carefully chiselling out the old case, checking the mortice pocket dimensions, and fitting the new lock so the bolt aligns cleanly with the keep.

A sash lock combines the same mortice deadlock mechanism with a sprung latch — commonly found on back doors, internal communal doors in blocks of flats, and older Bexleyheath terraced properties. Both types are well within our scope. When we replace a mortice lock we also check the door frame, the keep, and any anti-thrust plates, because a high-grade lock fitted to a weak frame still leaves the door vulnerable. Where we spot any concern, we tell you plainly and quote for any additional work separately — you decide whether to proceed.

A Yale-type nightlatch is a rim-mounted lock — the case sits on the inside face of the door rather than inside the door itself, and the cylinder passes through the door so the key operates it from outside. They are fast to operate, self-latching, and found on the vast majority of timber front doors in Bexleyheath. The weakness is that most standard nightlatches can be opened from the inside without a key, which is by design for fire safety, but it also means that if a burglar reaches through a letterbox or breaks an adjacent pane of glass, they can simply turn the knob and walk in. Upgrading to a double-cylinder nightlatch, or pairing the existing nightlatch with a properly rated mortice deadlock, removes that vulnerability entirely.

Rim cylinder replacement is one of the most common lock change jobs we carry out — it is straightforward, requires no structural work to the door, and immediately renders any outstanding keys useless. If you are a landlord in Bexleyheath whose tenant has just moved out, or a homeowner who has had keys go missing, this is usually the quickest and most cost-effective resolution. Our technicians carry a range of rim cylinders to suit standard British nightlatch cases, and we can advise on whether your existing nightlatch body is worth keeping or whether a full replacement of the rim lock case makes more sense at the same time. If you need this done urgently, call 020 3757 5689 — we answer 24/7 and send a locksmith straight away, usually reaching you within about 30 minutes.

A complete door lock replacement goes beyond swapping the lock itself. When our mobile locksmiths attend a property in Bexleyheath for a full replacement, the job typically includes: removing the existing mortice deadlock or nightlatch; inspecting the door edge, frame, and keep for damage or rot; sizing the new lock to fit the existing mortice pocket or drilling a fresh one where needed; fitting the new lock case or rim body; aligning and securing the striker plate or keep; testing the bolt throw and latch action through multiple cycles; and handing over the new keys with any relevant documentation for insurance purposes. Where the existing door furniture — handles, escutcheons, letterbox — needs to be temporarily removed and refitted, we do that as part of the same visit.

Bexleyheath has a wide mix of property types: Victorian and Edwardian terraces near the town centre, post-war semis out towards Barnehurst, and more recent flat developments closer to the Broadway. Timber doors on older properties often need a little more care — frames can have shifted over the years, and mortice pockets that were routed decades ago may not match modern lock case dimensions exactly. Our technicians are experienced in adapting to these variations and carry a selection of packing pieces and filler plates so the finished job is both secure and clean-looking. For uPVC doors, the cylinder is the primary serviceable component; if you are dealing with a uPVC door lock issue in Bexleyheath, we handle euro cylinder replacements on those doors too, including anti-snap cylinders that protect against a known forced-entry method common on that door type.

If you have been locked out in Bexleyheath, or if you are dealing with a lock that has failed and cannot wait, our 24 hour locksmith service means you will not be standing on your own doorstep for long. Before calling, it is worth checking whether a family member holds a spare key, whether a back or side door is accessible, or whether a letting agent or managing agent holds a copy — but if none of those options apply, our team is the right next call. We verify ownership or occupancy as standard before beginning any work, which protects you as much as it protects the property. Call 020 3757 5689 and we will send someone out straight away.

We know that lock problems rarely happen at convenient times, and we want you to understand exactly how our pricing works before you commit to anything. When you call us, we ask about the lock type, the door type, the job required, and your location within Bexleyheath or the surrounding area. Using that information, we calculate a quote that reflects the parts likely needed, the time of day — standard hours versus evenings, weekends, and bank holidays — and the travel involved. That quote is confirmed verbally before we set off. There are no additional charges revealed on arrival.

What we will never do is give you a vague figure on the phone and then adjust it at the door. The call-out charge is factored into the quote from the start. If, on inspection, the job turns out to be more involved than the initial description suggested, we stop, explain what we have found, and give you a revised figure before continuing. You are always in control of the decision.

A forced door rarely just needs the lock replacing. When a door has been kicked or shouldered, the frame, keep, and hinges absorb enormous force, and damage to these is not always obvious from the inside. Our approach after a break-in is to assess the whole door assembly before recommending a lock. Fitting a high-grade mortice deadlock into a split frame gives you a false sense of security, so we check and report on the frame condition honestly. Where frame reinforcement or a keep upgrade is needed, we quote for it at the same time.

For the lock itself, a break-in is a reasonable trigger to upgrade. If the existing lock was not BS3621-rated, this is the moment to fit one that is. If the door had only a nightlatch and no mortice deadlock, adding both is worth serious consideration for the insurance compliance angle alone. Our door lock replacement service in Bexleyheath covers both elements in a single visit wherever the door condition permits.