Window Security: What to Check
Use official guidance to review accessible windows, their locks, frames and opening restrictions before selecting a compatible upgrade.
Need help now? Call Albert directly — 24/7, no call centre.
024 7522 4730Improving a front-door cylinder does not address a window that is open, does not lock, or has damaged hardware. Window security therefore needs its own opening-by-opening check.
Police.uk's window-security advice recommends locking windows and paying particular attention to openings that are easy to reach. The source does not establish one timeless entry percentage or a universal split between unlocked and forced windows, so use the practical checks below rather than a fixed statistic.
Window Lock Types: What Is on Your Windows?
Cockspur Handles
Cockspur handles use a spur that closes over a receiver on the frame. Some are key-locking and some are not, so identify the exact handle and check that its spur engages correctly.
Problems arise when the handle, receiver, frame or alignment is damaged and the spur no longer engages as intended.
Check: Repair failed parts first, then consider a compatible locking handle or additional locking point if the complete window is sound.
Espagnolette Handles (Locking Handles)
Many uPVC windows use a handle connected to an espagnolette mechanism, which engages locking points around the opening. Operation varies, so check the manufacturer's instructions for the exact window.
If the handle feels loose, the key does not operate normally, or the locking points fail to engage, the handle, gearbox, alignment or another part may need attention.
Check: Have the mechanism assessed if the handle feels loose or the locking points do not engage. See the uPVC lock repair service for repair and replacement options.
Sash Jammers
A sash jammer is an additional device fitted to a compatible frame to restrict the sash from opening. Its contribution depends on the window, fixings, position and installation.
Not every jammer is compatible with every uPVC casement or tilt-and-turn window. Check clearances, reinforcement, operation and any escape requirement before fitting one.
Check: Consider one as a secondary locking point on a suitable accessible window; it must not substitute for a failed main mechanism. The fitted price depends on the device, frame and fixings.
Window Restrictors
Window restrictors limit how far a window opens. Select and install one for its documented purpose, and do not assume a restricted or partially open window is secured against entry.
Check: Follow the product instructions and any applicable safety or escape requirement. A restrictor is not a substitute for a functioning window lock.
Cable Window Restrictors
A cable restrictor uses a cable to limit opening; some versions require a key to release. Performance and suitability depend on the exact product, fixings and window.
Check: Confirm that the chosen product is suitable for the intended ventilation, child-safety and escape arrangements.
Condition Matters More Than an Age Cut-Off
Do not assume that a window is secure or insecure from its installation year alone. Check the actual condition and documented specification:
Any accessible window deserves a careful check if it does not close, align and lock positively, regardless of age.
uPVC Window Lock Upgrades
If the frame, sash and glazing remain serviceable, repairing or changing compatible hardware may avoid replacing the complete window. Compare a repair quote with any replacement option after the cause of the fault is identified.
Replacement Locking Handles
If a cockspur handle or receiver is faulty, replace it with compatible hardware that engages correctly. Key-locking options are available; the fitted price depends on the type and frame.
Sash Jammers
As described above, a compatible sash jammer may provide another locking point. Whether it is appropriate alongside a new handle depends on the complete window and its intended use.
Window Lock Bolts
These are separate key-operated bolts fitted to compatible window and frame construction. Confirm positioning, fixings, operation and any escape implications before installation.
Espagnolette Gearbox Replacement
If the handle moves but the locking points do not engage, the espagnolette gearbox, alignment or another component may be at fault. Diagnose the mechanism before replacing parts; the current fitted price depends on the exact replacement and condition.
Sash Window Security
Traditional sash windows require checks suited to their timber, fasteners, cords, alignment, ventilation and any conservation constraints.
Sash Window Checks
Sash Window Lock Options
For period properties, these locks can be fitted sympathetically without damaging the character of the windows.
Which Windows to Prioritise
Start with windows that are easy to reach, as Police.uk advises, while still checking that every window closes and locks.
High Priority
Medium Priority
Complete the Check
Cost of Window Lock Upgrades
This guide does not publish fixed per-window prices. A quote must identify the window type, diagnosed fault, compatible hardware, quantity and fitting work. Use the current prices page for listed locksmith starting prices and obtain a property-specific quote for anything outside those scopes.
Check the full price list for our complete range, or combine a window lock upgrade with a front door lock change for a full home security improvement.
Do I Need to Replace My Windows?
Not necessarily. If the complete window is structurally sound and compatible replacement hardware is available, a repair may be possible. Compare documented repair and replacement options rather than relying on a universal cost comparison.
Rotten timber, severe distortion, damaged glazing or failed sealed units may require work beyond a lock change. Ask the relevant window or glazing specialist to assess the complete unit.
What to Do Next
Walk around your home and check every window. Does each one close and lock as designed? Do its locking points engage, and is it reachable from ground level, a roof or another climbing aid?
If you are in Coventry or the surrounding areas and want me to check your windows, call 024 7522 4730. Share photographs or hardware details when booking so parts availability and whether a repair may need more than one visit can be confirmed.
You can also read the full home security checklist for everything else to check while you are at it.
Frequently Asked Questions
How much does it cost to fit window locks?
The fitted price depends on the window, fault, compatible handle or mechanism, fixings and number of openings. Call 024 7522 4730 with photographs or hardware details for a current property-specific quote.
What are sash jammers and should I fit them?
A sash jammer is an additional device fitted to a compatible frame to restrict the sash from opening. It is not suitable for every window and does not replace a failed main mechanism; check the frame, fixings, clearances and any escape requirement before fitting one.
Are my old uPVC windows a security risk?
Age alone does not establish a window's security. Check whether the sash, frame, handles and locking points are sound, aligned and operating correctly, and use documentation or a competent assessment for the exact specification. Repair may be possible if compatible parts are available.
I'm Albert, the independent locksmith behind Local Emergency Locksmith. These guides separate cited standards and public guidance from the checks that can only be made at the actual door. If you need a locksmith in one of the listed coverage locations, call me on 024 7522 4730 — I'm available 24/7.
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