What This Guide Covers and Who It Helps
Electromagnetic lock kits -- commonly called mag-lock kits -- combine a holding-force magnet, a power supply, and a release mechanism into a single access-control solution for commercial doors. This guide is written for commercial contractors, facility managers, and architects who need to select, specify, or troubleshoot mag-lock assemblies on projects ranging from school entry vestibules to healthcare corridor doors to industrial secure-area gates. It covers holding force selection, code-required egress provisions, installation realities, and maintenance considerations.
What Is a Magnetic Lock Kit?
A magnetic lock kit is an all-in-one electrified locking package that typically includes an electromagnetic lock body, an armature strike plate, a power supply, and at least one release device -- often a keypad, request-to-exit (REX) button, or motion sensor. The lock secures the door by energizing an electromagnet that bonds to the armature plate mounted on the door leaf. When power is interrupted -- intentionally or during a power failure -- the bond releases and the door is free to open.
Holding force ratings for commercial electromagnetic locks commonly range from around 600 lbs to 1,200 lbs. The right holding force depends on door size, traffic volume, and security level required -- not simply the assumption that more force is always better.
Where Magnetic Lock Kits Are Used
- Schools and universities: Controlled entry vestibules, classroom wing access doors, and administrative suite entries where keypad or credential-based access is required without sacrificing emergency egress speed.
- Healthcare facilities: Corridor doors in behavioral health wings, pharmacy access points, and secured patient areas subject to controlled-egress provisions under IBC and NFPA 101.
- Retail and commercial office: Tenant entrance doors, server rooms, stockrooms, and after-hours secured entries that must remain freely exitable during business hours.
- Industrial and warehouse: High-security equipment areas, loading dock entry doors, and maintenance corridors where the holding force must resist forced entry attempts but allow rapid evacuation.
Holding Force: How Much Do You Actually Need?
A 1,200 lb holding-force mag-lock is common for exterior and high-security interior doors. Lower-force models in the 600 lb range are appropriate for interior tenant doors, storage rooms, and lighter-traffic controlled access points. Over-specifying holding force on an interior office door adds cost without meaningful security benefit -- and can create problems during emergency egress if the fail-safe wiring or release devices are undersized relative to the lock.
Always match the lock's electrical requirements to the power supply included in the kit. Verify that voltage (typically 12 VDC or 24 VDC), current draw, and power supply capacity align before installation. A mismatch is one of the most common field problems with electrified hardware.
Code Compliance: The Non-Negotiable Layer
Electromagnetic locks on egress doors are regulated under both the International Building Code (IBC) and NFPA 101 Life Safety Code. The requirements below are general summaries -- always verify against the adopted edition in your jurisdiction and consult a code-qualified professional when in doubt.
Fail-Safe Behavior Is Required
Electromagnetic locks must be fail-safe: loss of power to the lock must automatically release the door. This is a fundamental requirement, not an option. It means that in a power outage, fire alarm activation, or system failure, the door is free to open from the egress side.
Egress Release Devices
Under IBC and NFPA 101, electromagnetically locked egress doors require at least one of the following release methods:
- Motion sensor (PIR) on egress side: The door unlocks automatically when an occupant approaches from the interior. Commonly used in high-traffic applications.
- Manual push-button release: Mounted 40 to 48 inches above the finished floor, within 5 feet of the door. Labeled "PUSH TO EXIT". Operation must directly interrupt power to the lock -- not route through the access control software. Door must remain unlocked for a minimum of 30 seconds.
- Hardware with built-in switch: Beginning with the 2007 IBC Supplement and reinforced in IBC 2012 and NFPA 101, a listed lever, pull handle, or panic bar with an integrated request-to-exit switch can serve as the sole release device. When the occupant operates the door hardware normally, the switch directly interrupts lock power and the door opens immediately. This is generally the cleanest, most user-intuitive solution.
Fire Alarm Integration Is Required
Mag-lock assemblies on egress doors must unlock automatically upon fire alarm activation and remain unlocked until the alarm is manually reset. Sprinkler or fire detection system activation carries the same requirement. This integration must be wired at the hardware level, not left to the access control software alone.
A Note on Misapplication
Code officials sometimes require PIR sensors and push buttons on any door with an electric lock, even where the mechanical hardware already provides free egress. This is technically an over-application of access-controlled egress provisions. If the door's mechanical hardware -- a lever, panic bar, or pull handle -- already allows free egress without electronic authorization, the full sensor-and-button package may not be required. Confirm with your AHJ early in the design phase to avoid unnecessary scope and cost.
Controlled and Delayed Egress Applications
In certain occupancies -- particularly healthcare Groups I-1 and I-2 such as behavioral health units -- controlled egress provisions allow approved locking on patient care corridor doors. Requirements include automatic sprinkler or smoke detection coverage, fire alarm and power-loss unlocking, and a UL 294-listed locking system. These are different and more restrictive than standard access-controlled egress. Never apply a standard mag-lock kit to a controlled or delayed egress application without verifying the full code path with your design team.
Installation Reality: What Installers Get Wrong
Even a properly specified mag-lock kit can underperform when installed carelessly. Here are the most common field issues:
- Armature plate alignment: The electromagnet and armature must make full surface contact to achieve rated holding force. Even a small gap or tilt significantly reduces holding strength. Take time to adjust the armature position after mounting.
- Power supply location: Mount the power supply in a protected, accessible location. Avoid attic or plenum locations where heat cycling or code restrictions on low-voltage wiring create problems.
- Door gap: Mag-locks require a consistent door-to-frame gap. Doors that rack, sag, or have inconsistent hardware adjustment will not hold reliably. Address the opening itself before attributing problems to the lock.
- Push-button wiring: The release button must be wired to directly interrupt lock power -- not signal the access control panel to release. A wiring path through the access control CPU does not meet code and will likely fail inspection.
- Weather-rated kits on exterior openings: Standard mag-lock components are generally rated for interior use only. If the application is an exterior or semi-exterior door subject to moisture and temperature extremes, confirm that all components -- lock body, armature, power supply, and keypad -- carry the appropriate environmental rating.
Maintenance and Long-Term Reliability
Electromagnetic locks have relatively few moving parts, which makes them lower maintenance than mechanical locksets over their service life. That said, a few practices extend reliability:
- Inspect armature plate contact surfaces annually for corrosion, paint buildup, or physical damage that could reduce holding force.
- Test fail-safe operation -- power interruption, fire alarm signal, and manual release -- on a scheduled basis. Most facilities managers schedule this with their fire alarm inspection.
- Verify that keypad or credential reader components are functioning correctly and that weatherproofing seals on exterior-rated units remain intact.
- Keep power supply capacity in mind if the security system is expanded; adding locks to an undersized power supply is a common cause of intermittent failures.
Choosing a Complete Kit vs. Individual Components
For straightforward applications -- a single controlled entry door with a keypad -- a pre-matched mag-lock kit simplifies specification, procurement, and installation. The power supply, lock body, and release hardware are engineered to work together, reducing the risk of voltage mismatch or incompatible wiring.
For more complex applications -- multi-door access control systems, integration with fire alarm panels, or credential-based networked access -- individual components selected by a qualified systems integrator often provide more flexibility and better long-term serviceability than a bundled kit. DoorwaysPlus carries electromagnetic lock hardware, power supplies, release devices, and electrified hardware components suited to both approaches.
Specifying Mag-Lock Hardware for Your Project
When building a hardware schedule or submitting for plan review, document the following for each electromagnetically locked opening:
- Holding force (lbs) and voltage/current draw of the lock
- Power supply capacity and location
- Release method (motion sensor, push button, or listed hardware with built-in switch)
- Fail-safe wiring confirmation
- Fire alarm integration method and panel compatibility
- UL 294 listing of the locking system components where required by occupancy
- Environmental rating if the opening is exterior or semi-exterior
Need help sourcing a complete electromagnetic lock kit or individual components for a specific opening? The team at DoorwaysPlus.com can help you match the right hardware to your application, occupancy type, and code requirements.