By installing a door chain, you are allowing the door to be partially opened to see who is
calling at the door. This allows protection against unwanted callers who may try to enter
your premises. A chain attached to the door hooks into a slot on the doorframe when the
door is closed. The only way to release the chain is by closing the door and unhooking it.
The strength is dependent on the anchorage of the kit to the door and frame. There are a
number of door chain kits available: a simple chain, a chain which can be unlocked from
outside with a key, a chain combined with a sliding bolt, and a chain with an in-built
alarm which is triggered when someone tries to enter. Use the longest, heavy gauged screws
possible to aid increased security.
It is a simple job to attach a security chain and no special skills are required.
Fitting a door chain
Decide on the convenient height of the chain. Use the device as a template and mark the
position of the screwholes on the inside of the door with a bradawl. Screw the device in
place and then, using a bradawl, mark the position of the chain holder on the frame at the
same height. Screw the chain holder onto the frame and check that the lock operates effectively.