A smart lock on a flat's front door: is it worth fitting?

How a smart lock differs from a standard cylinder swap

A cylinder swap replaces one part: the barrel that the key turns, inside the mechanism that is already fitted to your door. It takes half an hour, needs no wiring, and works with almost any door as long as the measurements match. A smart lock is a different proposition. Most models either replace the entire lock body, add a motorised unit on the inside face of the door, or fit over the existing cylinder to turn it electronically.

That means more to plan for: a power source, an app or keypad, and usually a bracket or plate that has to match your door's thickness and the position of the existing mortice lock. Some smart locks keep the original mechanical lock as a backup and simply automate it; others replace it outright. The first type is more forgiving of an older door, the second gives more features but demands a door in good condition.

Does your flat's door actually qualify

Many smart locks are designed for Western European door standards and assume a certain distance between the edge of the door and the centre of the lock, a certain door thickness, and a backset that is common in newer builds but not universal in Tallinn's older housing stock. Panel-block flats from the Soviet era, and the timber doors common in Kalamaja or Nõmme, often have narrower doors, different backsets, or mortice locks in positions that do not match the mounting plates supplied.

Before buying anything, measure your door's thickness, the backset of the existing lock, and whether the door has a metal reinforcement plate that a motorised unit would need to clear. If in doubt, photograph the lock area and the door edge and have someone check compatibility before you order — it is far cheaper to find out a model will not fit than to return it after drilling has started.

Battery and connectivity — the practical downsides

Every smart lock runs on batteries, typically lasting somewhere between six months and a year depending on use. Run them flat and you are locked out unless the lock has a backup key cylinder or an external terminal for a portable power bank — a feature worth checking for specifically, not assuming.

Wi-Fi and Bluetooth locks depend on a working connection to unlock remotely or send notifications; in a concrete stairwell, signal from your router may not reach the door reliably, and a dead phone battery defeats a phone-based lock entirely. Firmware updates, app accounts, and the manufacturer staying in business are all things a mechanical lock never asks of you.

• Check battery life claims against real winter use, not the marketing figure
• Confirm there is a physical backup — key cylinder or emergency power terminal
• Test Wi-Fi or Bluetooth signal at the door before committing to a connected model
• Ask whether the app needs an account with the manufacturer's servers to function at all
• Keep a spare set of mechanical keys somewhere accessible in case electronics fail

When your housing association's rules come into play

A front door within a flat is usually your own responsibility, but in many Tallinn apartment buildings the korteriühistu has rules about what can be fitted to entrance doors, particularly where doors are part of a shared stairwell's fire safety plan or where the building's insurance specifies a certain lock standard. Some associations also restrict visible changes to doors that face communal corridors.

If your building has a set of house rules, it is worth a quick check before fitting anything that changes the door's appearance or its locking mechanism, especially in older stock where the entrance door was replaced as part of a renovation and matches to a common design. This is a five-minute question to the board that avoids a dispute later.

When a smart lock is worth it, and when it is not

A smart lock earns its cost when several people need different access without cutting more keys — a short-term rental, a household with a cleaner or dog walker, or a family where teenagers keep losing keys. Being able to grant and revoke a code without changing the whole lock is the genuine advantage over a mechanical cylinder.

It is a poor fit if you live alone, rarely have anyone else needing access, or your door does not match common mounting standards without extra bracketry. In those cases a standard cylinder swap gives you the same security for a fraction of the cost and none of the battery anxiety. Fitting one is a job we already cover separately, and it remains the sensible default for most single-occupant flats.

What fitting involves and what it costs

Fitting a mechanical or backup-cylinder smart lock is close to a standard lock replacement: removing the old cylinder, fitting the new hardware, and testing the mechanism, which we price from 60 € per job depending on the lock and door. A fully motorised or bridge-style smart lock that needs wiring into a smart home hub, a hardwired power supply, or integration with an existing alarm system falls under smart home installation, priced from 90 € per job.

Either way it is worth having someone confirm compatibility with your specific door before the lock is bought, since returns on drilled or part-fitted hardware are rarely straightforward. A short visit to measure the door and check the mechanism costs far less than ordering the wrong lock twice.