How to fix a broken window lock

Casement windows

When an item breaks, it’s understandably frustrating. But when that item happens to be a window lock, it can leave you feeling more than just a bit frustrated. A broken window lock is a common issue, although one that can be rectified with the right know-how. So fear not, as this short guide will provide you with all you need to fix them yourself.

Fixing a broken window lock when the window is open

Generally, modern windows are fitted with espag locks, therefore the information in this guide is related to those.

If the lock has broken but your window is in an open position, you’ll just need to replace the window lock. You can do this by following this method:

1. Measure the distance from the edge of the window lock to the centre of the handle

2. Check the faceplate of the window lock for information on the manufacturer and the code. Having this information will allow you to find the replacement lock you require. Be sure your replacement is the same specification if possible

3. Remove the window handle and then the broken window lock

4. Place the replacement lock into the opening and line it up with the screw holes from where you removed the handle

5. Re-fit the handle

6. Fit the faceplate along the lock but make sure you use screws that are suitable for use on the material your window is constructed from

7. You may find that the new lock doesn’t fit into the existing receivers on the window. If this happens you’ll need to move the receivers. You can do this by removing the two screws that keep them in place. Next, adjust their height so the new lock fits into them, before screwing the receivers back in.

Fixing a broken window lock when the window is closed

If the lock breaks with the window in a closed position, you’re likely to find rectifying the issue considerably more difficult. You may also be required to mess around with the window seals, which is not recommended. You may void your window guarantee by doing this. Unless you’re well-versed in how your window locks operate, in this situation it’s best to call in the experts.

Chase Windows is a specialist home-improvement installer of windows, doors, conservatories & more. For more information, get in touch. Or for a look at our product range, why not browse our website.


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