Bolts can be used to provide extra security on external doors fit one to both top and bottom of the door. Barrel, padbolts and tower bolts can be screwed to the sur¬face of a door. Each has a long bolt which is generally shot into a staple (a hoop of metal) fixed to the door frame. Always choose a bolt with a heavy-duty staple and long fixing screws. Alternatively, the bolt may be shot into the sill or floor or into the door frame.
The bolts are neither key-operated nor deadlocking and so may be easily undone if access is possible. If you want to use one near glass, chose a padbolt – these can be secured by a padlock.
Flush bolts work in a similar way to tower and barrel bolts – in that they shoot a bolt into the frame and are non-locking – but they are designed to be mortised into the edge or face of the door. This makes them particularly suitable for double doors or where a concealed fitting is required.
You can get key-operated bolts which fit on the face of a door, but the better choice for a normal door is a mortise rack bolt.
For double doors which open out¬wards, fitting a mortise rack boll can be difficult and there is a special type of locking bolt which is fitted to the inner surface of the door and shoots a bolt up into a staple fitted to the underside of the top of the door frame. The lock is pushed to close: a key is needed to open it.
Because these locks are operated from the inside, they do not have as many key differs as external door locks.
Mortise rack bolts
These can be mortised into the edge of a wooden door and should be fitted so that the key is on the inside face. They are inconspicuous when fitted and will resist some forcing. The deadbolt is operated by a key and enters a striking plate mortised into the door frame. Each model usually has one universal key only. Some mortise rack bolts can be unlocked without a key these should not be used next to glass.
You should fit mortise rack bolls to both the top and the bottom of a door: on French windows, fit four not just two on the closing leaf. To do this you have to cut a mortise in the edge of a door in a similar manner to that described for Fit¬ting a mortise deadlock -but in this case the hole for the key should not be drilled right through the door.
These can be used with a hasp and staple (together often called a padlock bar) to lock garden sheds, garages and so on. The hasp is fitted to the door or gate and the staple to the frame. The padlock locks the two together. Choose a heavy-duty hasp and staple with fixing screws which are concealed when the padlock is in place. Use a closeshackle padlock which has the hoop (shackle) close to the body of the lock.
Other security devices for doors
Hinge bolts (sometimes called dog bolts). These provide protection against forcing (or even removal) of a wooden door from the hinge side, particularly doors which open outwards. The bolt enters the striking plate when the door is closed. They should be fitted to the top and the bottom of a door, close to the hinges. The bolt is usually mortised into the hinge edge of the door, but it may be surface mounted. The striking plate is rebated into the frame in a similar way to a mortise lock.
These prevent a door being opened more than a small amount (the chain is about 200mm long). A door limiter serves a similar function, but neither will provide more than limited protection, especially when the door is partly open. For full protection, a locking door bar is needed.
When fitting a door chain, position it close to the centre of the door and close to the edge to prevent marking the door when it is opened. The actual fixing is simple the chain receiving plate should be screwed to the door and the chain holding plate to the frame.
These allow you to see out¬side the door without opening it. Different models have different angles of vision – normally between 150 and 175 degrees. Choose one with as wide an angle as possible. Some models are made to fit different door thicknesses.
A door viewer should be fitted centrally in the door at eye-level and should be used in conjunction with a porch light.