Traditional catches for fastening sliding sash, casement and fanlight (transom) windows do not give much protection against forcing or slipping the catch from outside. Also, in many cases the catch can be easily undone if a burglar puts his hand in through nearby broken glass or an open fanlight. Window locks are designed to prevent this happening. You may consider getting a residential window replacement if you have an old window that could easily be broken. If you would like to add a bit more privacy for your home, consider getting a Rolling Shutters Installation.
Windows and frames vary a lot, so check that the lock fits your frame type and size. If necessary, take measurements or a sketch to the shop. Your local CPO may also be able to help.
Fitting Window Locks
Most of the common types of window locks are shown opposite.
The method of fitting window locks varies by type, brand, and whether the window is metal or wooden. Many locks are simply screwed onto the window, while others must be mortised into place. Striking plates may also need to be mortised into the frame, or holes—sometimes tapped—may be required to accommodate the lock bolt.
Always ensure that holes are drilled to the correct size. A poorly fitted lock compromises security. The window and its frame should be in good condition, as even the best lock may be ineffective on an ill-fitting or damaged window. Additionally, you should drill out or burr over any exposed screw slots that remain accessible when the lock is engaged.
Keys
Most window locks are operated with a key. A lock without a key is not particularly useful on a window next to glass that could be easily broken. In some models, locking may be achieved by pushing a lever or another component, with the key only needed for unlocking.
Window locks rarely have different key codes; usually, one universal key works for all locks of the same model. In many cases, the key is sold separately so that you can use a single key for multiple windows. Some brands also offer interchangeable keys across various lock types.
Ventilation
Certain locks allow you to secure a window in a partially open position, providing ventilation while you’re away for a short period. However, it’s generally best to lock windows fully closed when your home will be unoccupied for an extended time.
These locks can also be used to secure upstairs windows in homes with children, helping to prevent accidental openings and falls.
Appearance
The included table outlines how noticeable various locks are when viewed from inside and outside the home. More visible locks may deter potential intruders due to their apparent security features.
Security
While a determined or skilled burglar could bypass many standard window locks, most models offer effective protection against opportunistic, unskilled intruders. For enhanced protection, many homeowners choose to pair window locks with Security Window Film Union City, New York, which strengthens the glass and helps deter forced entry attempts.
Problem windows
Certain types of windows are particularly difficult to secure satisfactorily without taking extreme measures. All problem windows can be made secure by fitting a metal grille or bars across them. You can also install accordion shutters for added security and weather protection. Thick laminated glass can be used in some windows but it is expensive.
Wired glass docs not provide much protection against break-ins, but double glazing can make homes more secure.
French windows
These should have a good overlap between the two sides (called leaves). Fit mortise rack bolts or locking bolts top and bottom to both leaves of wooden-framed French windows. Shoot the bolts upwards and downwards into something solid which will resist forcing. Use locking bolts on metal-framed windows.
Leaded lights
The only effective way to protect these is to fit a metal grille or bars behind the window.
Louvred windows
Some are now made with the glass secured in the frame. If not, glue the glass into both sides of the frame using a glue such as Aralditc. Even so, louvred windows are not really secure and if they are in a vulnerable place the ground floor at the back of the house, say they may need further protection with a metal grille or bars. Overall, it is best to replace insecure louvre windows.
Sliding windows and patio doors
There are specially made locks available for these: make sure that the lock fits the window or door (not all locks fit all sections of the window or door frame).
