Windows are the most vulnerable part of any home’s security and you should fit locks to each one to deter would-be burglars.
Before doing so, check the condition of each frame. If wood is rotten or metal rusting then it’ll make the window frames a lot easier to force.
Faulty frames should be repaired immediately. Sections of soft and rotting wood should be cut out and replaced or filled as appropriate. Where paint is peeling, rub down the frames to bare wood, treat them with preservative, apply a coat of primer and undercoat and then finish off with a coat of gloss paint.
There is a wide variety of locks available for windows. The type you use depends largely on which sort of window you wish to lock and what it’s made of. There are two main categories of window locks: those that secure the window to the frame, and those that secure the handle in a locked position.
The ideal lock for a wooden casement window is a rack lock that deadbolts the window to the frame It is fitted in the same way as a conventional mortise lock on a door.
1. Mark the bolt position on the casement stile and drill a hole to accommodate the bolt.
Slide the bolt into place and mark the position of the front plate on the door edge.
Remove the bolt and cut the rebate for the front plate.
Mark and drill the key hole and then fit the keyhole cover.
Close the window and turn the lock several times to mark the positions of the bolt box.
2. Drill a hole to accept the box and fit it in place. Finally, fit the striking plate.
Fit two locks on each window, one at the top and one at the bottom. If you find the frame too narrow to accommodate the bolt then you should fit the locks in a vertical position. Larger rack bolts should be used on large casement windows. On French windows you have to fit the locks so that the bolts project into the top and bottom rails of the window frame.
If your window has rebated or narrow stiles, fit a special surface mounted lock.
3. To fit a surface mounted lock, first fix the lock section to the window stile. Mark the screw positions with a bradawl and screw it in place. Then with the window closed but the lock in the open position, mark the location of the staple on the frame and fix it in place.
In the closed position the lock covers all the screw heads. Fit two such locks on each window, about 100mm from the top and bottom.
Stay locks can be fixed to any casement window fitted with stays.
They fasten it in the closed position or allow you to lock the window slightly open for purposes of ventilation —although this won’t then prevent a burglar from sawing through 1 he stay itself.
4. Fit the base of the lock to the bottom of the frame or to the window casement — some models need to be screwed in position, others simply clamp on. All models will be locked by a key. If your stay is in poor condition, replace it with an aluminium one that incorporates a locking handle.
Locking handles can be fitted to side-hinged casement windows.
This type of lock includes a locking mechanism in the pivot point of the handle itself. Remove the old handle and fill any holes and make good the paintwork.
Screw the new handle halfway up the window frame and then position the catch accordingly. Some locking latches have two locked positions, one allowing for ventilation.
Cockspur locks hold the latch or handle blade in the closed position and so prevent the window being opened after the glass has been broken. They are most commonly used on metal frames.
Various types are available, but in all cases the body of the lock is fixed to the main frame of the window.
First close the window and mark the position of the lock so that it will grip the handle. On metal frames use a depth stop to prevent you from drilling into the glass of the window. Fit the lock using self-tapping or clutch-head screws.
Ordinary window locks or push locks are manually operated, but need a key to unlock them and release the window.
5.First mark the position of the lock both on the frame and on the opening casement. The backplate should be screwed to the opening casement, the lock to the frame. This should be fitted with the window closed and the lock over the backplate.
On metal framed windows, a locking bar is frequently screwed to the opening casement and a staple to the frame. The bar is locked over the staple to hold the window securely shut.
The simplest way to secure sash windows is to use screw stops or acorn stops. These allow the window to remain locked shut or to be opened by about 100mm to allow for ventilation. Fit two locks per window — one on each side of the sash. 6. Shut the window and drill a hole — usually about 12mm in diameter — in the side of the top sash, some 100mm above where the two sashes meet.
Screw in the thread, and then screw in the stops that will prevent the window being opened above that point.
Dual screws can be used on most windows, but are most effective on sash windows; however they don’t allow for any ventilation as they lock top and bottom sashes together. Check the rails are thick enough to accept the two screws. These are usually 13mm in diameter and the one for the lower sash is 38mm long and for the upper 21mm long. The screws should be fitted about 100mm in from the window edges.
7. Drill the hole through the inner sash and 21mm into the outer one.
Open the window and screw the threaded barrel into the hole through the inner sash. Use the key to drive the bolt through into the smaller barrel to lock the window in place.
A three-stage sash lock allows the window to be locked in one of three positions. A striking plate with three recesses is fixed to the side of the top sash, with the lock screwed to the top edge of the lower, inner sash.
Mark the position of the striking plate on the outer sash and cut out recesses using a brace and bit and squaring it off with a sharp chisel.
Screw it in position, making sure that it sits flush with the sash surface.
Fix the lock in place with clutchhead screws and check that it operates smoothly using the key provided.