One button, three mechanisms

The release button inside a flat looks identical in every building, but the hardware at the far end can be one of three systems. Which one is fitted decides how much force the door withstands, what happens in a power cut, and how often a fitter comes back over the years.

Electric strike

The common answer replaces the fixed keep in the frame with an electric strike. Press the button and the keep releases, so a push opens the door. The lock and handle on the leaf stay exactly as they were; only the frame component changes.

Simplicity and cost are its strengths. Resistance is its weakness: an electric strike is not as strong as a solid keep and can be strained when the door is yanked. On a communal entrance that opens a hundred times a day, the quality and adjustment of that strike decide the service interval.

Strikes come in two logics. Fail-secure types hold the door locked when power is lost; fail-safe types release it. Which one belongs on a given entrance depends on whether it forms part of an escape route, and that decision is taken alongside the building's fire strategy.

Magnetic lock

A maglock is an electromagnet on the frame holding an armature plate on the leaf. With no moving parts it barely wears, which suits very high traffic, and it needs no adjustment, which keeps maintenance low.

Two limits matter. A maglock holds by power, so a cut releases the door. That is an advantage on an escape route and an open risk where security comes first, where it has to be paired with a backup supply. Second, the magnet grips at a single point, usually the top edge, so the bottom corner of the leaf can flex when pushed.

Motorised multipoint lock

The third route motorises the door's own multipoint lock. The button withdraws the bolts, and they throw again when the door closes. This resists force best, because the mechanical locking points are kept intact.

Cost and cabling are the trade. The motor sits inside the leaf, so a flexible transfer carries the cable from frame to leaf, and that transfer lives on the hinge side where it moves every time the door opens. Routing a cable channel inside the leaf during production is far cleaner than improvising after installation.

Intercom: on the door or on the wall

A bell or video panel goes in one of two places: recessed into the leaf, or on the wall beside it. Recessing keeps the elevation tidy but mounts the panel on a moving part, so it is shaken at every opening and its cable rides the flexible transfer. A wall position is easier to maintain and replace, because the wiring behind it never moves.

If the panel is going into the leaf, a solid panel area has to be planned for it. That decision changes the glazing ratio, so it is taken before the pattern is chosen. A recessed mailbox follows the same rule.

Settle before production

  • Lock type: electric strike, maglock or motorised multipoint.
  • Locked or released on power failure.
  • Which frame edge the cable enters, and whether it crosses into the leaf.
  • Intercom panel on the leaf or on the wall.
  • Overhead closer or floor spring.
  • Card or keypad reader, and where it goes.
  • Whether this is an escape route, which fixes swing and lock logic.

The cable starts in the frame

Electrified hardware causes most trouble before installation, not during it. Cutting a cable route after the frame is fixed into the wall is awkward and looks it. State which frame edge the cable enters when the door is ordered, and the profile is drilled in production so the cable runs concealed. Likewise, naming the closer type early lets the top edge of the leaf be reinforced for it.

Once the opening sizes, the electrical provision and the escape status are clear, the hardware list and the door composition are planned together and quoted as one package. Models in building entrance doors can be prepared for any of these systems; for a second door on an escape route see fire doors, and for villa and gated entrances see glazed villa steel doors.