Magnetic vs Electric Locks: Which Is Right for Your Property?

If you are considering an access control upgrade for a commercial property, a block of flats or a secured gate, you will quickly encounter two main electrical locking options: magnetic locks (maglocks) and electric strikes. Both can do the job well in the right context. They work differently, fail differently, suit different applications, and carry different installation requirements. This guide is for property managers, business owners and landlords in South London who want to understand the practical differences before commissioning any work.

How Magnetic Locks Work

A magnetic lock uses an electromagnet mounted on the door frame and a steel armature plate mounted on the door itself. When current flows through the electromagnet, it generates a holding force that keeps the door shut. Commercial-grade maglocks typically produce a holding force of 600 to 1,200 pounds (272 to 544 kilograms) — more than sufficient for most residential and commercial applications.

The most important characteristic of a maglock is that it is fail-safe by nature. When power is cut, the magnet releases and the door opens. This is not a flaw — it is a deliberate design choice. In a fire emergency, power to the maglock is cut automatically via the fire alarm panel, and all magnetically locked doors open immediately. UK fire safety legislation generally requires that electrically locked doors on means of escape fail to the open position. Maglocks have no moving parts, giving them a long service life with minimal maintenance.

How Electric Strikes Work

An electric strike replaces the conventional strike plate in the door frame. When power is applied or removed (depending on configuration), the strike's keeper pivots to allow the latch or bolt to pass through without a key or handle turn. The door can then be pulled open from outside, while retaining the physical lock mechanism for normal operation.

Electric strikes can be configured as either fail-safe (door opens on power loss) or fail-secure (door remains locked on power loss). This choice is fundamental and depends on the application. A door on a fire escape route must be fail-safe. A server room or secure storage area might legitimately be fail-secure, provided occupants can always exit freely. Unlike a maglock, an electric strike works alongside the door's existing lock hardware — you keep the physical latch or mortice bolt and simply add electrical control over the strike.

Where Each Type Is Typically Used

Maglocks are most common on glass doors in office receptions, gate entrances, communal doors in blocks of flats, and any door where a completely flush finish is preferred. Because there are no mechanical components in the door leaf itself, they work well on lightweight aluminium-framed glass doors.

Electric strikes are preferred where a door is already fitted with a physical mortice lock or latch and the requirement is simply to add remote or keypad access. They integrate naturally with intercom systems on residential blocks and are often the better option in smaller commercial premises where a single entry point needs to be buzz-operable from a reception desk.

For some installations, getting an initial assessment from a security locksmith before commissioning electrical work is worthwhile. Our locksmith service can confirm whether the door is in suitable condition to accept either type of fitting. The Metropolitan Police crime prevention guidance also offers practical advice on physical security for business premises.

Power Requirements and Infrastructure

Both maglocks and electric strikes require a 12V or 24V DC power supply. A standard maglock draws around 250 to 500 milliamps continuously while active — a real but modest power draw over a 24-hour period. For both systems, cabling from the power supply to the door frame needs to be routed to current wiring standards.

A rough budget for supplying and fitting a single maglock with power supply and a basic keypad access reader in South London is £300 to £600, depending on the cable run length and the specification of the card reader or keypad.

Power Failure Behaviour and Fire Safety

Power failure behaviour is one of the most consequential differences between the two systems and connects directly to legal obligations around fire safety. A fail-safe maglock releases on power loss, so locked doors open automatically — correct for doors on escape routes but unsuitable for secure storage. Most commercial installations pair a maglock with an uninterruptible power supply (UPS) to provide short-term continuity during brief power interruptions.

A fail-secure electric strike remains locked during power loss. This is acceptable on certain internal secure areas but is not permitted on any door that forms part of a means of escape. Almost every door which staff or members of the public might use as an exit needs either a fail-safe strike or a mechanical override such as a push-bar, a green break-glass key switch, or a dedicated manual release button.

Pros, Cons and Cost of Installation

Maglocks: No moving parts, long service life, high holding force, inherently fail-safe, suited to lightweight glass doors. Downside: require continuous power to stay locked, visible on the frame, holding force degrades if the door warps. Cannot be fitted to outward-opening doors without special L-bracket or Z-bracket hardware.

Electric strikes: Preserve the door's existing lock hardware, can be configured fail-safe or fail-secure, less visually intrusive. Downside: contain moving parts that wear over time, require a door with a compatible latch or bolt, more complex to install on fire-rated doors.

For a single maglock on an internal or communal door with power supply and basic access panel, budget £300 to £500 for supply and installation. An electric strike installation on an existing door with a new two-way intercom system typically runs from £250 to £600. Multi-door systems with centralised access control, card readers and audit trail logging cost significantly more.

Frequently Asked Questions

Can a maglock be fitted to an outward-opening door?

Yes, with additional hardware. An L-bracket or Z-bracket is used to position the armature plate correctly on an outward-opening door. This adds a small amount to the installation cost and requires careful measurement, but it is a standard solution for any experienced installer.

Are maglocks permitted on fire escape doors in the UK?

A fail-safe maglock that releases automatically when the fire alarm activates is acceptable on a fire escape door, provided the door also has a mechanical override allowing it to be opened if the alarm does not trigger. The specific requirements depend on your building's fire risk assessment — confirm with your local fire authority before installation.

Do I need planning permission to fit an electric lock or maglock?

In most cases, no. Fitting access control to an existing commercial or residential door is not normally a change requiring planning permission. However, if the property is listed or within a conservation area and installation involves visible surface mounting or physical changes to the building fabric, checking with your local planning authority before any work begins is advisable.

How long does a maglock last?

A quality electromagnetic lock, correctly installed and maintained, will typically function for ten to fifteen years. The main maintenance requirement is keeping the armature plate clean and confirming periodically that the door has not warped to a degree that reduces contact between magnet and plate.