If you are in any doubt about a security problem, go to your local police station and seek the advice of the crime prevention officer. CPOs can be found in virtually every area of Britain and their experience and knowledge of security devices, including details of how to fit them, will prove invaluable. The service is free.
Over 60 percent of household break-ins occur through windows; intruders choose this route because an unsecured window can be quickly opened from outside. For example, it could take an experienced burglar less than 15 seconds to enter a house through a casement window by breaking or removing a pane. There is a wide range of window security devices (WSDs) available to secure windows properly, preventing easy access and causing as much obstruction as possible to an intruder. It is worth fitting these to all the windows in your house, even to those which are above the ground floor, since an agile intruder could scale a drainpipe or building projection or climb scaffolding or a ladder which has been carelessly left out. Fanlights should also be protected, as should small permanently shut windows, since once the glass has been removed these can provide access for a slim intruder. Fitting most WSDs is within the capability of the home handyman; usually, you will find any experience you have gained in installing mortise locks or bolts on doors will be valuable since fitting WSDs often requires similar tools and expertise. Remember too that although an intruder may gain access through a window, he may be unable to retreat through the same opening since the stolen goods may be too large; you should make sure all exterior doors are secured as well.
Preparing for installation
Start by making a plan of window locations and note the size and type of each window and its existing fittings. Check how frequently windows are usually opened since this is a feature you should consider when choosing the WSD you will fit. Examine windows for loose joints and panes and look for rotten sections in timber frames; complete any repair work before fitting security devices.
Window security devices fit to and secure existing fittings or are fitted between moving and fixed window sections. The costs of individual WSDs car vary considerably, but as a general rule those which are fitted to existing fittings semi-permanently are cheaper than key-operated types which are fitted permanently to fixed and moving frames and allow windows to be opened quickly. When selecting WSDs it is best to avoid choosing cheaper semipermanent types for windows which are regularly opened since they will need to be frequently removed from and replaced on the fitting and may be lost or not used as a result. Anti-child locks Care should be taken in selecting WSDs for households with young children; in this case the devices will be used to prevent windows being opened easily from inside as well as outside. Devices which lock directly onto handles and stays are suitable since these are difficult to remove.
Where screw heads securing WSDs are visible from outside, it is worth using clutch head screws since these cannot be unscrewed. Alternatively you can file the heads of slot head screws and drill out the heads of cross head screws so they cannot be undone with a screwdriver.
WSDs for timber casements
Timber casement windows are usually fitted with cockspur handles and window stays; securing them can involve replacement of these fittings with more secure types or installing devices which give extra security in addition to the existing fittings.
Replacement handles and stays are available in matching sets of various designs and may involve the use of conventional or special keys. With one make, the handle is secured with a conventional key and the lockable window stay can be secured in up to nine positions; so while ventilation is provided, opening the window from outside is extremely difficult. Both the handle and stay are fixed in position using the screws provided.
There is a variety of window locks available. One type fits flush to the edge of the window and you move a catch to lock a bolt section fitted to the opening frame into a keep recessed into the fixed frame when the window is closed; when you want to open the window undo the lock with the key supplied. There is a version of the same lock for use with metal frame windows and the same key can be used for both versions. Another type of device locks automatically when the window is closed, in case you forget to lock up. You use a key to open the window.
If you have young children in the house, make sure the keys to locks are not in an easily accessible position since children can quickly learn how they are used.
Window security bolts
These are slightly smaller than the security bolts which are used to fit on doors; fitting them involves basically the same process. The bolt section and its casing are mortised into the edge of the opening frame in a central position and, when operated by a splined key, the bolt locks into a plate recessed into the fixed frame; the width of the frame should be 38mm minimum. Security bolts have the advantage of being virtually invisible from outside. On larger casement windows, if the window frame depth will accommodate them, you can use larger door security bolts to give extra bolt depth.
Window security bolts usually require a depth of at least 38mm, plus suitable glazing clearance; so measure your window frame carefully to make sure its depth is sufficient before buying this type of device.
These are inexpensive, easily fitted, threaded units which replace the existing stay pins. If they are in good condition, you can use the screws which secured the old stay pin to secure the new threaded pin; but remember the screws will be accessible when the window is secured in some open positions and treat as described above.) The thread passes through the existing hole in the window stay and is secured from above by a special nut, which is tightened with the key supplied. You can secure a window in a partially open position by fixing through the hole further down the stay; however, since this means removing the locking nut, stay locks are best used on windows which are infrequently opened. One type of stay lock is available for securing window stays without holes; it is fitted using two screws and is secured with a special locking key.
Other locking devices
A number of small locking devices, usually operated with special keys which lock the moving and fixed parts of timber frame windows together, are also available.
Locks for metal casements
As with timber casement windows, metal ones are usually secured with cockspur handles and window stays and, again, there is a variety of devices you can fit to provide a proper level of security.
With one typical variety the lock is fixed to the opening part of the window frame and the bolt locks into the fixed frame to secure the window. Special fixing screws are supplied to ensure strong fixing to metal window frames. The keys of this type of lock are interchangeable with those for a version designed for timber windows.
There are several other WSDs for securing existing fittings. For example, cockspur handles on metal frame windows can be secured by a device which fits on the fixed frame beneath the handle. When the window is closed, a bolt is locked in an upright position to prevent the cockspur portion of the handle passing; if you want to open the window, you can release the bolt with a special key. This device is fitted with the self-tapping screws provided; you should drill holes for these according to the manufacturer’s instructions. When fitting, make sure the swing of the cockspur misses the bolt body. To secure the handle in the ‘shut’ position on a window which is infrequently opened, you can fit a device which locks directly onto the cockspur using the special key provided – no tools or screws are necessary.
Securing window stays
These fittings can be secured to a metal frame in several ways. They include a device which you can fit to the existing stay without screws or fixing tools; it locks the stay to its retainer to prevent stay movement and the window being opened.
This is fitted in the edge of the casement; when locked with an oval-shaped key, it secures the casement to the frame. It is fitted by drilling one hole (using the template provided) through the casement and securing the lock with an escutcheon screw.
For securing other types of window, you can sometimes use the devices available for casement windows; but there are devices which are manufactured specifically for use in these situations.
Otherwise known as vents and usually situated above larger casement windows, these are normally fitted with window stays; you can us€ stay locks to secure them if there is a suitable timber sub-frame. There is a D-shaped clamping device available which is specially designed to prevent stay movement in metal frame transom windows; it is easily fitted with screws.
Timber sash windows
These can often be opened from the outside since the centre latch can be undone by a knife or similar tool. If the windows are opened infrequently, you can secure them with strong screws. Otherwise, you can flt a device operated with a special key; a protruding bolt prevents the two sliding panes passing. There are several types available. With one type the bolt is fitted to the upper sash about 100mm above the striking plate which is fitted to the top of the lower sash. When the key is turned until the bolt is fully extended, the window may be opened a small distance to provide ventilation, but any attempt to force it will be thwarted when the bolt hits the striking plate. Other types have the bolt fixed to the top of the lower sash; the bolt locates in one or more locking plates on the upper sash to coincide with the fully closed and slightly open positions. Again, the bolts are released with a key.
Metal sliding windows
These are generally fitted with special locks which provide good security. For extra protection, you can fit a device which snaps onto the sliding window runner and prevents window movement; another device locks onto the frame. For many types of metal sliding window, you can fit a patio door lock to provide additional security.
Centre pivot windows
These are best secured by the window locks available for casement windows. A window lock with versions for both metal and timber frame windows will adequately secure pivot windows with frames of either material.
For these, the window locks available for casement windows are usually appropriate. Many fanlights have narrow frames and this is a point to consider when buying locks.
Securing fixed pane windows
Most homes have at least one small fixed window; to provide adequate security, this should be glazed with 6mm thick wired glass. Check the interior beading is strong and securely fitted so it will withstand any attempts at forcing it. Where you have a window with a large fixed pane, make sure the frame is in good condition and the pane is properly secured. Where a large fixed window is in a particularly vulnerable position, such as a basement area, it is worth considering the installation of a security grille or iron bars.
In some situations, these are the only effective means of providing protection against intrusion. They are supplied in designs to match the existing decor and character of the house. Installation of a grille is best left to the specialist.
These should be round iron of not less than 19mm diameter or square iron of not less than l9mm section. They should be fixed vertically to the inside of the window at l25mm intervals ; grout them into the brickwork at the top and bottom of the window to a depth of at least 50mm and recessed at least 50mm from the wall surface. The bars should pass through flat horizontal iron tie bars, the distance between which should not exceed 450mm, and kept in position by welding or flattening the bars above and below the tie bars. The ends of the tie bars should be cut, splayed and grouted into the brickwork.