UPVC window locks fail in predictable ways: handles spin loosely instead of throwing the espagnolette, gearboxes wear out and stop engaging the locking points down the frame, windows drop so the keeps are misaligned, and decades-old mechanisms simply stop responding. All four are routine same-visit fixes for us.
We carry the most common espagnolette gearboxes, handles, tilt-and-turn drives, friction stays and child-safety restrictors as standard van stock — Roto, Maco, GU, Yale, ERA and Avocet parts cover over 90% of UK windows from the 1990s to date.
Single window from £49 fitted. Full-house upgrades (6–8 windows) typically £199–£299 fitted with keyed-alike handles where wanted. All work carries a 12-month guarantee.
The four most common UPVC window faults
Loose or spinning handle: the gearbox inside the handle has stripped. The handle physically turns but the espagnolette below it doesn't move. Handle plus internal gearbox replacement, £49–£79 per window.
Window won't close or lock: the espagnolette gearbox (the long mechanism running the full length of the window) has worn out, or the window has dropped so the locking points no longer align with the keeps. £59–£89 per window for the part; realignment included.
Stuck open or stuck shut: usually a seized espagnolette — the internal mechanism has corroded or jammed. Free-up if possible (sometimes works), otherwise replace the gearbox. £49–£89 per window.
Broken handle key or lost handle key: handles supplied keyed-alike or to a master key suite. New cylinder-key handles £25–£45 per window fitted.
Tilt-and-turn windows
Tilt-and-turn UPVC windows use a more complex internal drive that controls both the side-hung opening and the top-hung tilt position. The most common failures are: drive gearbox seizes mid-position (window stuck part way), tilt restrictor breaks (window opens fully when it should only tilt), or handle gearbox strips so the drive no longer engages.
We carry Roto NT, Maco i.S. and GU UNI-JET drive kits as standard. Most tilt-and-turn replacements are 30–40 minutes per window, £79–£129 fitted depending on the brand.
Child-safety and ventilation restrictors
UPVC windows above ground floor level should have either child-safety restrictors (preventing a child from opening the window more than 100mm) or restrictor stays that let you ventilate without leaving the window unsecured. Both are required by building regs in many situations and recommended for any household with children.
We fit cable restrictors (£25–£35 per window), key-lockable restrictors (£35–£50 per window) and friction stays as a retrofit on existing UPVC windows. Typically 10–15 minutes per window once on site.
Whole-house upgrades
If multiple windows are failing or you want to bring the whole house up to BS 7950 insurance spec, a full-house visit is far better value than individual call-outs. A typical 6–8 window UPVC house is a single 3-hour visit, £199–£299 fitted, including new keyed-alike handles where wanted so one key works every window.
We supply matching white or chrome handles, your choice. Tilt-and-turn windows are quoted separately as the parts cost more.



