Property managers ask us one question more than any other: should this door get an electric strike or a maglock? The answer depends on the door type, the fire rating, the occupancy, and what happens when the power goes out. Get it wrong and you void a fire rating, fail a fire marshal inspection, or lock people inside a building during an emergency.
This article covers what each device does, when to use it, and the code requirements that govern the choice. Every claim is sourced to the relevant code section or manufacturer documentation.
What Is an Electric Strike?
An electric strike replaces the fixed strike plate in a door frame with an electrified version. Inside the strike body, a solenoid controls a movable keeper — a hinged, spring-loaded tab that holds the door’s latchbolt in place.
When the access control system sends a release signal (or, on a fail-safe unit, removes power), the keeper pivots. The latchbolt passes through. The door opens without retracting the latch — the lock body itself never moves. The frame side yields.
The key point: the lock cylinder and inside lever stay fully functional. Anyone on the egress side can still turn the knob or lever and exit by retracting the latch normally. This is why a correctly fitted electric strike preserves free egress and is acceptable on required exit paths. From outside, a mechanical key still works as a fallback when electronics or power fail.
What Is a Maglock?
A maglock (electromagnetic lock) has two parts: an electromagnet mounted to the door frame, and a steel armature plate mounted to the door. When the electromagnet is energized with DC power, it creates a magnetic field that pulls the armature plate against the magnet face. The bond holds the door closed. When power is cut — intentionally, by fire alarm, or by power failure — the magnetic bond releases instantly and the door swings freely.
Holding force ratings:
| Holding Force | Application |
|---|---|
| 600 lbs | Traffic control only — light interior, low-risk |
| 1,200 lbs | Commercial standard — aluminum/glass doors, most commercial interior |
| 1,500+ lbs | High security — hollow metal doors, high-traffic |
Per SDC (Security Door Controls), any maglock with less than 1,200 lbs holding force should only be used for traffic control. 1,200 lbs is the de facto commercial standard because aluminum/glass doors typically shatter before a 1,200-lb maglock releases.
Fail-Safe vs. Fail-Secure
This is the single most important distinction. It determines what happens when the power goes out.
| Configuration | Power ON | Power CUT | Also called |
|---|---|---|---|
| Fail-safe | Locked | Unlocked — door releases | Fail-open, fail-unlocked |
| Fail-secure | Unlocked | Locked — keeper stays secure | Fail-locked |
Fail-safe stays locked when power is applied and unlocks when power is cut. During a power outage, the door is free to open. Required on doors that must release on fire alarm. Used on stairwell doors, exit corridors, and assembly egress paths.
Fail-secure stays locked when power is cut and unlocks when power is applied. During a power outage, the door stays locked from the outside — but the inside lever or knob still allows free mechanical egress. Maintains security during power loss. Common on perimeter doors, server rooms, restricted areas, storage rooms.
Every maglock is fail-safe. There is no fail-secure maglock. The electromagnet requires continuous power to hold. No power means no bond means the door opens. This is inherent to the technology, not a configuration choice.
Many modern electric strikes are field-selectable — fail-safe or fail-secure, switchable on-site in seconds without disassembly. Some accept dual voltage (12/24V DC).
Fire-Rated Doors: The Hard Rule
This is where most installations go wrong.
Fire-rated doors require fire-rated (UL 10C listed) fail-secure electric strikes. The strike must keep the door latched when power is lost, so smoke and flame cannot pass. A fail-safe strike would release the keeper on power loss, unlatching the door and voiding the fire rating.
From Securitron/Seco-Larm documentation: “To maintain the fire rating, [the strike] must be used in Fail-Secure mode only. If it is used in Fail-Safe mode, the fire rating becomes invalid, and the ‘Listed Fire Rated Hardware’ label must be removed.”
Maglocks cannot replace the latch on a fire-rated door. NFPA 80 Section 6.4.4.1 requires that “only labeled locks and latches or labeled fire exit hardware shall be used” on fire door assemblies. A maglock does not provide positive latching. Removing the mechanical latch and replacing it with a maglock is a “serious deficiency that could have tragic consequences” per the NFPA 80 Handbook.
A maglock can be installed on a fire-rated door as an auxiliary lock — but only if the mechanical latching hardware remains in place and functional, the maglock itself is labeled for fire door use (UL 10C), and all egress code requirements are met. In practice, fire-rated electric strikes or electrified panic hardware are preferred on fire-rated openings.
Fire Alarm Integration
The fire alarm system must be able to release all electrified egress locks upon activation. This is not optional. It is code.
NFPA 72 Section 21.9 governs the interconnection between fire alarm systems and door locking systems:
- 21.9.1 — All exits required to unlock by the fire alarm system must do so upon receipt of any fire alarm signal.
- 21.9.6 — Doors that unlock on fire alarm must remain unlocked until the fire alarm condition is manually reset.
- 21.9.3 — Secondary power supplies (batteries) must not hold egress doors locked for more than 10 minutes after loss of primary power.
- 21.9.4 — Independent fail-safe lock power supplies that unlock on power loss are exempt from the 10-minute rule.
The interface works through a listed fire alarm relay module at the lock power supply. When the fire alarm activates, the relay changes state and cuts power to the maglock. The relay module must be located within 3 feet (1 meter) of the controlled circuit per NFPA 72. A signal to the security system is NOT acceptable — the security system is not rated as life-safety equipment.
Battery backup is a code-sensitive issue. A battery that keeps a maglock energized during a building power outage violates IBC 1010.1.9 Condition 1 (release on loss of power). Best practice: battery backup sustains the access control panel, readers, and request-to-exit sensors — not the maglock circuit itself. The maglock circuit must drop on power loss and fire alarm.
Building Code Requirements
The International Building Code (IBC) Section 1010.1.9 governs electrified egress doors. The default rule: egress doors must be “readily openable from the egress side without the use of a key or special knowledge or effort.”
Three special locking arrangements apply to maglocks and electric strikes on egress doors:
Sensor-release systems (IBC 1010.1.9.9 / NFPA 101 7.2.1.6.2): A sensor on the egress side detects an approaching occupant and releases the lock. Three release methods must all be present simultaneously: (1) loss of power unlocks the door, (2) a manual push-to-exit button located 40-48 inches above the floor within 5 feet of the door, labeled “PUSH TO EXIT” in letters at least 1 inch high on a contrasting background, and (3) fire alarm or sprinkler activation releases the door. The system must be listed to UL 294.
Door-hardware release systems (IBC 1010.1.9.10 / NFPA 101 7.2.1.6.3): A switch built into the door-mounted hardware (panic hardware, lever, sensor bar with REX switch) directly interrupts lock power. The hardware must be obvious in its method of operation, operable with one hand, and must unlock immediately upon actuation.
Delayed-egress systems (IBC 1010.1.9.8 / NFPA 101 7.2.1.6.1): The door holds for up to 15 seconds (or 30 seconds where approved by the AHJ) after the egress device is actuated, then releases. An audible alarm sounds during the delay. The delay must deactivate on sprinkler actuation, heat detector, or two smoke detectors. Signage is required: “PUSH UNTIL ALARM SOUNDS, DOOR CAN BE OPENED IN 15 SECONDS.” Not permitted in Group H (high hazard) or Group I-2 (healthcare).
Broward County HVHZ Requirements
Broward County is in the High-Velocity Hurricane Zone (HVHZ), defined in FBC Chapter 1620. Design wind speeds are 170 mph (3-sec gust) for Broward. All exterior building products — including doors and their listed hardware — must carry a Miami-Dade Notice of Acceptance (NOA) or Broward Product Control approval and pass TAS 201/202/203 test protocols. Standard UL and ANSI certifications alone are not sufficient for exterior HVHZ applications.
Always verify a product’s FL number or NOA on the Florida Building Commission product approval database before specifying electric hardware for an exterior door in Broward or Miami-Dade.
When to Use Which: Decision Matrix
| Door type / application | Use this | Why |
|---|---|---|
| Fire-rated door | Fail-secure electric strike (UL 10C) | Fire doors must stay latched on power loss; fail-safe would void the rating |
| Stairwell re-entry door | Fail-safe electric strike | Must release on fire alarm for re-entry (NFPA 101 7.2.1.5.7) |
| Exit corridor, assembly egress | Fail-safe electric strike or maglock | Life safety priority — doors must release on fire alarm/power loss |
| Server room, data center | Fail-secure electric strike | Security priority during power loss; mechanical egress from inside still works |
| Storage room, utility closet | Fail-secure electric strike | Security priority; mechanical egress from inside |
| Perimeter door (security priority) | Fail-secure electric strike | Maintains security during power outage |
| Glass/aluminum storefront door | Maglock | No lock prep for an electric strike — only practical surface-mounted option |
| Door with panic hardware, no frame cutout | Maglock or surface-mounted electric strike for rim device | Cannot install mortise/cylindrical strike |
| Pair of doors with mullion | Maglock or surface strike | Surface-mounted solution |
Common Installation Mistakes We Fix
Maglock on an egress door with no fire alarm integration. Code violation. The fire alarm panel must be able to cut power to the maglock. If it can’t, the door is non-compliant and will fail a fire marshal inspection. Required by IBC 1010.1.9.9 and NFPA 72 21.9.
Fail-safe strike on a fire-rated door. Voids the fire rating. The keeper would release on power loss, unlatching the door. Must be replaced with a fire-rated fail-secure strike.
Maglock replacing the mechanical latch on a fire door. Serious deficiency per NFPA 80 Handbook. The mechanical latch must remain in place and functional.
Undersized wiring causing voltage drop. Long wire runs with 18 AWG wire can drop voltage below the lock’s operating range. A 1,500-foot run of 18 AWG at 0.3A drops 2.91V — fine at 24V (87.9% remaining) but fails at 12V (75.75%). Always calculate voltage drop and increase wire gauge for long runs.
Battery backup holding maglocks during a power outage. Violates IBC 1010.1.9 and NFPA 72 21.9.3. Battery backup should power the access control panel and readers, not the maglock circuit.
Power supply sized for steady-state only, ignoring inrush. Maglocks and electric strikes draw 5-10x their holding current for 50-100 milliseconds at activation. Sizing only for holding current causes controller reboots and unreliable operation. Best practice: sum worst-case currents, add 20-50% headroom, round up to the next standard supply size.
What Happens During a Power Outage
| Configuration | Door behavior on power loss |
|---|---|
| Fail-safe electric strike | Unlocks — door releases |
| Fail-secure electric strike | Stays locked from outside; mechanical egress from inside still works |
| Maglock (fail-safe by design) | Unlocks — door releases. Building becomes unsecured. |
For a building with maglocks on all egress doors, a power outage means every maglock door unlocks. If security during outages matters — and for most commercial buildings, it does — consider fail-secure electric strikes on perimeter doors, or accept that life safety overrides security during a fire or power failure.
Who Does What: Locksmith vs. Electrician vs. Fire Alarm Contractor
A properly installed electrified lock system typically involves three trades:
Locksmith (door hardware): Strike or maglock selection, frame prep, mounting, lock cylinder and keying, panic hardware integration, fire door compliance, NFPA 80 field modification verification. The locksmith leads the door-side work.
Low-voltage contractor: Power supply wiring, conduit, voltage drop calculations, battery sizing, access control panel installation.
Fire alarm contractor: The fire alarm relay interface (NFPA 72) usually requires a licensed fire alarm contractor. A permit is typically required for fire alarm integrations. The fire alarm contractor wires the relay module that cuts power to the maglock on fire alarm activation.
Need Electrified Lock Hardware Installed?
Pro Locksmith LLC installs and services electric strikes, maglocks, and electrified panic hardware for commercial buildings across Broward, Miami-Dade, and southern Palm Beach.
Licensed and insured. Employees, not subcontractors. Flat-rate pricing quoted before work starts. COI provided for commercial properties. Free commercial site walkthrough to assess your doors, identify code requirements, and specify the right hardware for each opening.
Call (954) 406-8266 or fill out the form below.
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