Lockers are usually physically joined together side by side in banks, and are commonly made from steel, although wood, laminate, and plastic are other materials sometimes found. Steel lockers which are banked together share side walls, and are constructed by starting with a complete locker; further lockers may then be adding by constructing the floor, roof, rear wall, door, and just one extra side wall, the existing side wall of the previous locker serving as the other side wall of the new one. The walls, floors, and roof of lockers may be either riveted together (the more traditional method) or, more recently, welded together.
Locking options: various types of key locking or padlocking facility are available now. Key locking options include flush locks, cam locks, or locks incorporated into a rotating handle; padlocking facilities may be a simple hasp and staple, or else a padlocking hole may be included in a handle, often called a latchlock. More modern designs include keyless operation, either by coin deposit (which may or may not be returned when use of the locker terminates), or by using electronic keypads to enter passwords for later reopening the locker. Some older lockers used a drop-latch which was incorporated into the door handle, and slid up and down and could be padlocked at the bottom in the "down" position, but these are less used now. Three-point locking is not possible with this type of latch, because it needs to be operated by means of a latch that rotates rather than slides up and down; so this drop-latch is probably a less secure locking option, which may be why it is little used nowadays. Prefect Combination locks are very popular in school lockers used in the UK due to their ease of use and the time and cost saved in the removal of locker keys.