The first step in creating a bank vault is to build its wall panels. These are made from concrete with zero ‘slump’, a quality that means it is super-strong and sets very quickly when put into the moulds. While the concrete is still damp, steel rods are inserted to provide extra strength.
The entire moulds are then vibrated for several hours – this oscillation settles the concrete around the rods and eliminates any air pockets. Once the panels are fitted, the vault door can be made. This involves creating a core panel of concrete and then cladding it in reinforced stainless steel.
The door is slotted into the wall panels by metal struts. When the door is done the locking mechanism can be installed, which is placed on the inward side of the door for obvious security reasons. Typically a dual-combination lock is used, which requires two people to synchronously dial in for the door to open. Finally, a suite of alarm sensors is installed both inside and around the vault. These include CCTV video cameras, laser trip-wires, motion sensors and decibel sensors.