Updated September 16, 2026.
If you're evaluating maglocks because propped-open doors keep defeating your access control, or because an old electric strike is buzzing every time someone badges in, this guide covers the practical decisions you'll face: how these locks actually secure a door, where they fit, where they get you crosswise with the fire code, and what to ask before you buy.
Short answer first: a magnetic door lock system uses an electromagnet mounted to the door frame and a steel armature plate on the door itself. Send power to the magnet, the door locks. Cut power, the door unlocks. Everything else — readers, request-to-exit devices, fire alarm interfaces, buttons — is just deciding when and how that power gets cut.
How a Magnetic Door Lock System Actually Works
An electromagnet is a coil of wire wrapped around a steel core. Push current through the coil and the core becomes a magnet; stop the current and it goes inert. In a maglock, that electromagnet lives on the door frame, usually at the top. A flat steel armature plate is bolted to the door. When the two meet and the coil is powered, they clamp together with steady, continuous force. There are no moving parts, no latch, and no bolt sliding in and out.
Holding force is the most-quoted spec. Common commercial ratings include 600 lb and 1,200 lb units, with higher-capacity models available for double doors and outward-swinging exterior openings. Wilcox Door Service's buyer guidance offers a reasonable rule of thumb: lower-holding-force units for low-risk interior doors, mid-range units for server rooms and secondary entrances, and 1,200 lb or higher for primary entrances and restricted areas. Treat those numbers as a starting point, not a spec — match the lock to the door and the threat, and confirm the rating against the manufacturer's UL 294 listing.
The critical behavior to understand: maglocks are fail-safe by design. If power stops, the door releases. That's a feature for life safety — everyone can walk out during a building-wide outage — and it's a limitation for security, because losing power also means losing the lock. Compare that to an electric strike, which is typically fail-secure (loss of power keeps the door locked). Neither approach is universally better; they solve different problems, and picking the wrong one is one of the most common design mistakes. If you want the plain-English version of how these fit into the bigger picture, our explainer on the three types of access control walks through where maglocks slot in versus discretionary and role-based setups.
Where Maglocks Belong (and Where They Don't)
Maglocks are a good fit for:
- Glass storefront doors where you can't cut into the frame for a strike
- Aluminum-frame commercial entries with narrow stiles
- Interior secured doors (IT rooms, records rooms, back-of-house)
- Perimeter gates with the right weatherproof housing
- Double doors where you want clean symmetric hold
- Any door where silent operation matters (strikes buzz, maglocks don't)
Maglocks are a poor fit for:
- Wood residential doors, where the frame warps and misaligns the plate
- Doors that must stay locked during a power outage (some data centers, cash rooms, weapons storage)
- Doors that swing outward, unless you use a specialty shear maglock
- Any door where the local code requires specific hardware (see next section)
Confirm the complete exit arrangement
An electrically locked egress door needs a permitted release arrangement for the applicable occupancy and adopted code edition. Allegion’s overview of electromagnetic-lock requirements distinguishes sensor-release and door-hardware-release arrangements. It is background from a particular publication date, not a site approval.
Have the qualified designer and responsible authority identify the required release devices, loss-of-power behavior, fire-system interface, listings and signage for each opening. Delayed-egress arrangements need their own review. Do not copy a timing value or wiring diagram from a general article into a live exit system.
For equipment selection after that review, browse Monarch’s access-control catalog.
Exit alarms, release devices and acceptance
A door-position alarm reports a condition; it is not the same function as releasing a lock so a person can leave. Ask the installer to identify each component’s purpose and show how the complete arrangement follows the approved design.
Document who tests the opening, what conditions are included and where results are kept. Include ordinary exit operation, the applicable power-loss behavior and any required fire-system interaction. Coordinate testing with the responsible professionals so it does not interfere with the building’s safety systems.
Use the exact manufacturer’s instructions for mounting, power supplies and cable sizing. Keep the approved configuration and maintenance responsibilities at handover. Do not choose a different voltage, bypass a release device or add backup power without confirming the effect on the approved exit arrangement.
Picking, Installing, and Living With a Maglock
Choosing the right maglock is mostly about understanding the door.
Door type. Glass storefront? You'll need a Z-bracket or top-jamb bracket to give the armature something to bolt to — you can't drill into tempered glass. Hollow metal frame? Standard surface mount works. Wood door? Reinforce the header or the lock will loosen over time. Outward-swinging? Use a shear lock, which recesses into the edge of the door and frame instead of sitting on the surface.
Environment. Interior climate-controlled space? Any commercial maglock works. Exterior gate exposed to rain? Use a weatherized housing with an appropriate IP rating and stainless hardware. High-humidity environments like pool decks and commercial kitchens will corrode uncoated coils.
Traffic and abuse level. A quiet side door with a few dozen uses a day is a different problem than a main entry with heavy traffic. High-traffic doors misalign faster, faces get dirty, and any gap or contamination between the magnet and armature will reduce clamping force. Keep the mating surfaces clean and check alignment on a regular maintenance schedule; consult the manufacturer's datasheet for the specific tolerance range they publish for a given model.
Installation issues worth catching before they cost you:
- Frame flex. If the door frame moves when the door slams, the armature will rock off the magnet face over thousands of cycles. Reinforce the frame before mounting the lock.
- Grounding. Some access panels tie the maglock's negative side to chassis ground; others don't. Read the panel manual before wiring.
- Inductive spike suppression. Maglocks are inductive loads. When power drops, they generate a voltage spike that can damage the relay controlling them. Install the manufacturer-supplied MOV or diode across the coil terminals — it's the difference between a relay that lasts a long time and one that fails early.
- Bond sensor wiring. Most modern maglocks include a bond sensor that reports whether the magnet and armature are actually in contact. Wire it into the panel. It tells you the door is genuinely locked, not just closed.
For a broader look at where maglocks sit inside a full access control design, the three types of access control breakdown is a good next read. When you're ready to price hardware — locks, listed power supplies, request-to-exit devices, controllers — Monarch's access control catalog has code-compliant options across the range.
Questions to ask any vendor or integrator before you sign
- Which code pattern is this install — sensor release, door-hardware release, or delayed egress — and which occupancy class does it fall under?
- Has the local AHJ signed off on the specific release design, including the fire alarm interface where required?
- Is the power supply UL-listed for access control, and how long is battery backup sized to run this door?
- Is the lock listed to UL 294 (Standard for Access Control System Units), and does the adopted edition of your code require that listing?
- Who is responsible for annual inspection and testing of the release hardware, and what does that documentation look like?
- On a door-hardware-release install, is fire-alarm release still being provided (even though it's not code-required for that pattern)? If not, is that acceptable to the AHJ and to your insurer?
Contact Monarch with the site requirements to discuss the next step.
FAQ
Does a magnetic door lock system unlock during a power outage?
Yes — that's the fail-safe design. When power to the electromagnet cuts, the magnetic field collapses and the door releases. This is required for egress doors under the codes discussed above, and it also means you need a UL-listed access control power supply with battery backup sized to your requirements if the door should stay secure during short outages. For long outages or facilities where the door must not unlock, an electric strike or motorized lock is a better fit.
How much holding force do I actually need on a commercial door?
Match holding force to the risk and traffic on the specific door. General guidance from Wilcox Door Service suggests lower ratings for low-risk interior doors, mid-range units for server rooms and secondary entrances, and 1,200 lb or more for primary entrances and restricted-area doors. Double doors typically use either two locks or a purpose-built double-door unit. Confirm the rating against the manufacturer's UL 294 listing rather than marketing copy.
Can I install a maglock on a wood residential door?
It's possible but rarely a good idea. Wood doors and frames flex and warp with humidity, which misaligns the armature and reduces holding force. For homes, a smart deadbolt or electric strike paired with a proper lockset is almost always the better answer.
Do maglocks meet fire code on egress doors?
They can, when installed under one of the recognized code patterns (sensor release, door-hardware release, or delayed egress) with the required release devices, power-loss behavior, and — where the pattern requires it — fire alarm interface. The specific requirements differ between the two patterns; the sensor-release pattern requires fire alarm release, and the door-hardware-release pattern does not. Confirm the design with your AHJ before install, not after.
What's the difference between a bond sensor and a door position switch?
A bond sensor reports whether the magnet and armature are actually in contact and holding — the door is truly locked. A door position switch reports whether the door is closed. A door can be closed but not properly locked (misaligned plate, dirty face, dropped power), so a bond sensor gives you the real answer. Wire both into the access panel for full situational awareness.
How long do magnetic locks typically last?
A quality commercial maglock installed correctly can run for many years with minimal maintenance beyond occasional cleaning of the magnet face, because there are no moving parts to wear out. Failures usually come from installation issues (loose armature, undersized wire, missing spike suppression) or environmental damage (corrosion on outdoor units without proper weatherization), not from the electromagnet itself.