Most smart-lock comparisons are written by people selling smart locks, and it shows: long on app screenshots, silent on the question that decides everything for a British home — will it work with your door at all? The majority of UK front doors are uPVC or composite with multipoint locking, and the majority of smart locks you will see advertised were designed for a different kind of door entirely. As locksmiths, we fit smart locks, we like good ones — and we also attend the failures. This is the comparison we give customers at the kitchen table.
Start here: the compatibility question nobody leads with
The famous deadbolt-style smart locks come from North America, where doors take a single round deadbolt. A British multipoint door has no deadbolt to replace — it has a strip of hooks driven by a euro cylinder, engaged by lifting the handle. For these doors, realistic smart options are: a smart euro cylinder (replacing the cylinder itself), a handle-mounted unit that turns the cylinder for you, or a full smart multipoint conversion. Each still depends on the door's mechanics: a smart motor cannot lift a stiff handle, and a dropped door that needs a shoulder will defeat a gadget that a service visit would have saved.
Timber doors are more permissive — smart nightlatches and retrofit units fit more readily — but the rule stands either way: the door must work flawlessly by hand before anything smart goes near it.
Security: the honest comparison
Where traditional wins. A mechanical lock cannot run flat, crash, or be phished. Its certifications are mature and insurer-recognised: Kitemarked BS3621 on timber, TS007 three-star or SS312 Diamond cylinders on multipoint doors. A burglar facing good mechanical hardware needs noise, time and risk — the three things they hate.
Where smart locks win. They remove the human errors that cause real burglaries: doors left unlocked (auto-locking closes them), keys under plant pots (revocable codes replace them), keys with cleaners and trades (time-limited access instead), and the lost-keys problem (revoke, not re-key).
Where smart locks lose, in practice. Our call-outs tell the story: flat batteries on units without a decent mechanical override; apps that update badly at midnight; motors straining against misaligned doors until something gives; and cheap imports whose underlying cylinder is the snappable kind our anti-snap guide warns about — a computer bolted to a weak lock is a weak lock with notifications.
The insurance angle
Policy wording was written for keys: "key-operated locks", "five-lever mortice deadlock", "multi-point locking". A keyless installation can drift outside that wording without anyone noticing until claim time. Two protections: choose smart hardware whose mechanical core is itself certified (smart cylinders with TS007 ratings exist, and BSI now assesses smart locks under TS621), and tell your insurer in writing what is fitted. Boring, five minutes, decisive.
Who each suits
- Strong smart-lock cases: Airbnb and holiday lets (codes per guest), HMOs and house-shares (revocable fobs), carers and cleaners on schedules, anyone who keeps losing keys, and households who want the "did I lock it?" question answered from the sofa.
- Strong traditional cases: exposed coastal or hard-weather doors, properties left empty for long stretches, anyone uneasy about batteries and apps guarding the family home, and budgets where the same money buys top-tier mechanical hardware for every door instead of electronics for one.
- Renters: the lock usually belongs to the landlord — written permission first, and favour units that leave the original hardware intact.
The configuration we actually recommend
This is rarely an either/or. The setup that earns its keep in real homes is smart convenience layered over certified mechanical security: a rated anti-snap cylinder (or Kitemarked mortice lock) doing the resisting, with the smart layer handling access — and always, always a physical key override that lives outside the house. Smart features expire with batteries and firmware; a three-star cylinder is as strong in ten years as the day it was fitted.
The five-question buying checklist
- Does it physically suit a UK multipoint/euro-cylinder door — not just "fits most doors"?
- Is the mechanical core certified (TS007 stars, SS312, BS3621/TS621) rather than just the electronics?
- Is there a proper key override, with the spare kept off the premises?
- How does it behave when the battery dies — warning, external power option, override?
- Has the door itself been serviced so the mechanism moves freely by hand?
Answer those five honestly and either choice — smart, traditional or the hybrid — will serve you well. Skip them and no amount of technology, old or new, will compensate.
