Window Won't Lock or Close Properly? Here's What to Do
22 May 2026 · 5 min read
A window that won't lock isn't just annoying — it's an open invitation. The good news: most causes are a quick, affordable repair, not a new window.
Why it matters
A window that will not lock or close properly is a genuine security weakness and lets in draughts and rain. Burglars look for exactly this kind of easy access point, so it is worth fixing promptly rather than living with it.
The reassuring part is that most causes are mechanical and inexpensive to put right — you rarely need a whole new window.
Common causes
The usual culprits are a broken or worn handle, a failed locking mechanism or gearbox inside the frame, dropped or worn hinges that throw the window out of alignment, or a uPVC frame that has expanded slightly in hot weather. On older timber and sash windows, swelling, paint build-up, or worn fittings are common.
Sometimes it is simply a build-up of dirt in the mechanism, but a stiff or failing lock usually points to a part that needs replacing.
How it is repaired
A glazier can replace handles, locks, gearboxes, and hinges, realign sashes, and adjust the window so it closes and locks smoothly again. These parts are widely available, so most repairs are completed quickly on the first visit.
Replacing a faulty mechanism restores the lock to the security it was designed to provide — far cheaper than replacing the window.
Don't leave it
If a ground-floor or accessible window will not lock, treat it as a priority. In the meantime, keep it closed and consider additional security until it is repaired.
We can attend, identify the faulty part, and restore secure operation — usually in a single visit. Just give us a call to arrange it.
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