Most access control content online covers which system to buy — biometric vs. card vs. PIN. Fewer cover what actually happens on the door itself once you've decided. That's what this page is for: the hardware choices, wiring considerations, and one safety requirement that matters more than most buying guides mention.
Door Hardware: The Part That Actually Locks the Door
The access control reader (fingerprint scanner, card reader) decides who gets in. A separate piece of hardware actually locks and unlocks the door. Getting this part wrong is the most common source of access control installations that look right but don't work reliably.
Magnetic Lock (Maglock)
An electromagnet mounted on the door frame holds an armature plate on the door shut. Strong holding force, no moving parts to wear out — but a magnetic lock must be wired fail-safe, meaning it unlocks automatically on power loss. This isn't optional on most doors; it's a fire-egress requirement covered below.
Electric Strike
Replaces the door's existing strike plate with an electronically controlled one, working with the door's existing latch. Can be wired either fail-safe (unlocks on power loss) or fail-secure (stays locked on power loss) depending on what the door actually needs — an electrical room might reasonably stay secure during a power cut; a fire-exit-adjacent door generally should not.
Electric Bolt / Deadbolt
A more secure option than a strike, often used on higher-security doors, but generally requires fail-safe wiring for the same egress reasons and isn't typically used on primary fire-exit paths.
The Fire-Egress Requirement Most Guides Skip
This is the single most important thing to get right, and the thing we check first during any installation: a locked door must never trap someone inside during an emergency. In practice, this means:
- A request-to-exit device (button or motion sensor) or a mechanical free-exit handle must allow anyone to leave from the inside without needing a credential, regardless of the locking hardware
- Locking hardware on primary escape routes is generally wired fail-safe, so a power cut doesn't leave the door locked
- This isn't a suggestion — it's a real safety requirement, and installing access control that overrides free exit is not something we will do, regardless of what's requested
We assess this for every door during the site survey, not as an afterthought — it affects which hardware is even appropriate for that specific door before cost or brand is discussed.
Does Installation Require Modifying the Door?
Depends on the hardware chosen:
- Electric strikes require replacing the existing strike plate — a real modification to the door frame, though usually not the door leaf itself
- Magnetic locks are surface-mounted on the frame and door, needing less cutting into the hardware but still requiring secure mounting on both
- Glass doors need hardware specifically rated for glass mounting — not every lock type is compatible, and this gets confirmed before any hardware is ordered
- Fire-rated doors need fire-rated compatible hardware to avoid compromising the door's rating — this is checked, not assumed
Wiring and Power
Access control needs power run to the reader, the lock hardware, and the controller — typically low-voltage cabling, often alongside a backup battery so the system keeps functioning through a brief power interruption without defaulting to an unsafe locked or unlocked state unexpectedly. Where an existing door already has cabling (from a prior system or intercom installation), we assess whether it can be reused before running new cable.
Installation Process
- Site survey — door type, existing wiring, fire-egress requirement for that specific door, and integration needs (intercom, CCTV, attendance system)
- Hardware selection — matched to the door type and required fail-safe/fail-secure behavior, not a default one-size choice
- Installation — reader, lock hardware, controller, wiring, and backup power
- Configuration — user enrollment, access schedules, and confirming the request-to-exit function works correctly before anything else
- Testing — including a deliberate power-cut test to confirm the door behaves correctly (unlocks if fail-safe) before handover
- Handover — walkthrough of user management so your team can add/remove access independently afterward
Timeline
A single door with existing wiring access typically takes a few hours. Multi-door commercial sites, or any door needing new cable runs, are scheduled across a full day or longer depending on scope.
Frequently Asked Questions
A magnetic lock holds the door shut with an electromagnet and releases on valid access; an electric strike allows the existing door latch to release electronically. Magnetic locks are generally stronger but must fail-safe (unlock) on power loss for fire-egress compliance; electric strikes can be configured either way depending on the door's use.
It depends on the hardware. Electric strikes typically require replacing the door's existing strike plate; magnetic locks are usually surface-mounted and need less modification to the door itself, but do require secure mounting on the frame and door leaf.
Yes, but the hardware must be fire-rated compatible and the installation must preserve the door's fire-rating and free-exit requirements — this is assessed during the site survey, not assumed.
A single-door installation with existing wiring access typically takes a few hours; multi-door commercial installations or sites needing new cable runs take longer and are usually scheduled across a full day or more.
Related Reading
For help choosing which system fits your property, see our guides on access control for small offices and villa vs. office access control. For our full access control service details and to request a quote, see Access Control Systems.