Electric Door Strikes for Gyms: Everything You Need to Know

If you want to control your gym's door remotely — whether via an app, a fob reader, or a phone-based system — you need an electrically-controlled door mechanism. The most common options are electric door strikes and electromagnetic locks. Here's what they are, how they work, and which one you need.

What is an electric door strike?

An electric door strike replaces your existing door strike (the plate mounted in the door frame that the latch clicks into). An electric version has a solenoid inside: when power is applied, the mechanism releases and allows the door latch to push through, opening the door. When power is removed, the strike returns to its locked position.

They come in two variants: fail-secure (locked when power is off — what you want for a gym) and fail-safe (unlocked when power is off — used in emergency exits).

What is an electromagnetic lock?

An electromagnetic lock (mag-lock) uses a powerful electromagnet mounted on the door frame that clamps to a metal plate on the door. When the magnet is energised, the door is locked. Cut power and the door opens. These are inherently fail-safe — if power dies, the door releases.

Mag-locks can hold 300–600kg of force and are very reliable. But because they fail-safe (open on power loss), they're not ideal as your primary gym entry lock — you'd need a backup mechanism to ensure the door stays secure during a power outage.

Which is better for a gym?

For most small NZ gyms, a fail-secure electric door strike is the right choice. It:

• Installs into the existing door frame without replacing the door or lock body
• Defaults to locked if power or internet goes down — the security default you want
• Operates on 12V DC — safe for a DIY or basic electrician installation
• Compatible with standard door sizes and commercial hollow-core doors
• Typically costs $80–$200 NZD for the hardware itself

What voltage and current do you need?

Most commercial electric strikes operate on 12V DC (some also support 24V). The relay that controls them — including the Raspberry Pi relay unit used by Latch — outputs 12V DC when triggered. The Latch device includes the appropriate power supply; you just connect the strike to the relay output terminals.

Compatible door types

• Aluminium-framed commercial doors: compatible with most strikes
• Timber-framed doors: compatible with standard residential-spec strikes
• Steel security doors: may need a higher-force strike or a deadbolt override
• Sliding doors: not compatible with standard strikes — need a different mechanism
• Glass pivot doors: typically use a mag-lock mounted at the top

Do I need an electrician?

The electric strike itself runs on low-voltage DC (12V) from a wall adapter — this is safe and doesn't require a licensed electrician in NZ. The wall adapter plugs into a standard 240V outlet. If you're running the 240V power supply wiring through walls or ceilings, that part requires a registered electrician. But the low-voltage cabling between the power supply, the Latch device, and the door strike can be done by any competent person.

Recommended strikes for NZ gyms

• Adams Rite 7400 series — widely available, commercial grade, works with most aluminium frame doors
• Trimco / TESA electric strikes — good quality, available through NZ locksmith suppliers
• Generic 12V electric strikes from TradeMe/Amazon — work fine for most installs at $80–$120 NZD