Mortice Locks & Yale Nightlatches

A 5-lever mortice deadlock is a single integrated unit: the bolt mechanism, the levers, and the keyhole all sit inside the lock case that is morticed into the door edge. There is no separate cylinder to swap as there is with a euro-profile lock. If your existing mortice lock is not BS3621 compliant, the whole case needs to be replaced. Our technicians will check whether your current lock carries the BS3621 kitemark — it is usually stamped on the faceplate or the case — and advise you accordingly before any work begins.

If the latch operates smoothly but the key has been lost or copied without your knowledge, changing the cylinder alone is usually sufficient and avoids disturbing the case mounting on the door. If the latch is stiff, the spring is weak, or the case has been damaged in a break-in attempt, replacing the whole case is the better option. When we attend, we assess both before recommending anything, and we explain the reasoning so you can make an informed decision.

In most tenancy agreements, changing the locks without the landlord's consent is a breach of the tenancy terms, because the landlord retains a right of access for inspections and emergencies. The practical and legally safer route is to contact your letting agent or managing agent first and ask them to arrange the lock change, or to get written permission before instructing us. We are happy to speak with managing agents directly if that helps move things along. In an emergency — for example if you have genuine safety concerns — please call us and explain the situation; we will advise on the most appropriate steps.

Purchasing a BS3621 lock from a hardware shop is straightforward enough, but correct fitting requires the right tools, the right mortice dimensions, and experience reading a door's condition. A poorly fitted lock — one where the bolt does not engage fully in the keep, where the pocket is too shallow, or where the door frame has not been assessed — can fail under relatively modest force even if the lock itself is a quality unit. A trained technician will also spot secondary issues such as a misaligned door frame or a weakened door edge that you would not necessarily notice, and address them so the lock performs as the standard intends.

We operate 24 hours a day, every day of the year — evenings, weekends, and bank holidays included. When you call 020 7871 7825, we send a locksmith straight away and are usually with you in about 30 minutes, though we cannot guarantee an exact arrival time as it depends on where our nearest operative is at that moment. We will give you a realistic expectation when you call and keep you updated if anything changes.

This is more common than people expect on the older timber doors found throughout Kentish Town's Victorian terraces. If the mortice pocket is enlarged from a previous break-in, or if the door edge is split or soft, we assess the extent of the damage on site and explain the options. In many cases we can carry out or advise on reinforcement work at the same time as the lock fitting. Where damage is severe enough to require a joiner, we will tell you clearly and not proceed in a way that leaves the lock inadequately supported. Our aim is always a genuinely secure outcome, not just a completed job.