UPVC door locks fail in three distinct ways — and we fix all three on the same visit. The internal multipoint gearbox can wear out and stop throwing the hooks and deadbolts (the most common failure). The euro cylinder can seize, snap or get a key broken inside it. Or the door can drop on its hinges so the gearbox jams against the keep — fixable with realignment, longer hinges and packers.
We carry every major UPVC gearbox brand on the van as standard: Yale Doormaster, ERA Vectis, GU Secury, Fuhr Multisafe, Maco, Avocet WS and Winkhaus. We also carry TS007 3-star anti-snap cylinders (Avocet ABS, Brisant Ultion and Mul-T-Lock) for upgrades, and the alignment packers and extra-long hinges needed to fix dropped doors. Over 90% of UPVC failures in our patch are first-visit fixes with no parts ordering.
Pricing is fixed and agreed before the engineer sets off — £79–£149 covers virtually every repair, fitted, with a 12-month workmanship guarantee. There is no premium for nights, weekends or bank holidays once the quote is agreed.
How to tell what's wrong with your UPVC door lock
Diagnose before you call — it saves time on the phone and means we set off with the right parts. The four most common symptom patterns map cleanly onto the four most common failures.
Key turns freely but nothing happens, and the handle won't lift to throw the hooks: the multipoint gearbox has failed. The gear teeth inside the central case have worn or stripped, and the keyway no longer drives the cam that throws the hooks and bolts. Replacement is a bolt-out, bolt-in job that takes around 45 minutes on the door. The part itself is £45–£95 depending on brand; total fitted price typically £109–£149.
Key won't turn, or only turns part way with serious resistance: the euro cylinder has failed. This is often the cheapest UPVC repair — a new cylinder is £25–£60 plus fitting. If you'd like to upgrade to a TS007 3-star anti-snap cylinder at the same time (recommended by every major UK home insurer), add £30–£60 for the higher-spec part. Total fitted typically £79–£129.
Handle lifts but the door still won't lock, and you can see the hooks/bolts move only partially: door drop or gearbox jamming against the keep. The fix is realigning the door on its hinges (often with longer-shaft hinges and packers to compensate for the sag), then checking the gearbox isn't damaged from being forced. £79–£129 typical.
Key is snapped off in the cylinder: broken-key extraction. We extract the broken section non-destructively in 90%+ of cases — the cylinder is fine afterwards and the key can be cut from the other half. £55–£89 typical. If the cylinder is damaged in the process, we replace it on the same visit.
Why DIY UPVC lock repair almost always costs more
It's the most common phone call we get: 'I tried to fix it myself and now it's worse'. Three things go wrong when householders attempt UPVC repairs without the right tools and parts.
First, the gearbox is a sealed precision unit — once it's out of the door, the springs and cams inside fall out of position the moment you flip it over, and it's almost impossible to reassemble. We see DIY-disassembled gearboxes regularly; they're scrap.
Second, the wrong cylinder length will leave the lock either flush (insecure) or protruding (snappable). The right length is measured in 5mm increments either side of centre, and getting it wrong by 5mm is the difference between secure and trivially defeated.
Third, and most expensive: levering the cylinder out of a stuck mechanism almost always damages the gearbox at the same time. A £30 DIY cylinder swap turns into a £140 gearbox + cylinder replacement.
We're not saying don't try — but if the door is your only way in and out of the house, a £79 fixed-price call-out with a 12-month guarantee is usually the cheaper route.
Which gearbox brand is in your UPVC door?
Most UK UPVC doors built between 1995 and 2015 use one of about ten common multipoint gearbox brands. You can usually identify yours from the centre case if you take a photo with the door open — the brand and part number are stamped on the metal faceplate.
Yale Doormaster (most common across 1990s and 2000s estate builds), ERA Vectis (very common on Reading-area estates from 2000 onwards), GU Secury (premium builds and conservatories), Fuhr Multisafe (north-of-Thames new-builds), Maco (composite doors from Solidor and similar), Avocet WS (general retrofit), Winkhaus (heritage and high-spec builds).
Send us a photo of the gearbox faceplate via WhatsApp and we'll confirm the part is on the van before we set off. We carry all of the above as standard stock — if yours is something less common, we can usually source a same-day match.
Replacing the cylinder at the same time — and the TS007 upgrade
If we're already replacing the gearbox, upgrading the euro cylinder at the same time costs almost nothing extra in labour — the door is already open and the cylinder is already out. We strongly recommend a TS007 3-star (Sold Secure Diamond) anti-snap cylinder upgrade whenever we're on site, because the original 1990s/2000s cylinders are the single biggest weak point in a typical UPVC door.
Anti-snap cylinders have a sacrificial section that snaps off cleanly without exposing the working mechanism — defeating the most common burglary technique used against UPVC doors across the UK. The cost premium is £30–£60 over a standard cylinder, and every major UK home insurer recommends or requires them (AXA, Aviva, Direct Line, LV=, More Than, Hiscox).
We fit Avocet ABS, Brisant Ultion and Mul-T-Lock TS007 3-star cylinders as standard — all carry the kitemark and Sold Secure rating insurers ask for.
What to expect when you book us
Call or WhatsApp us with the symptoms. We'll diagnose on the phone, quote a fixed total (everything included — call-out, labour, parts, VAT), and give you an arrival window. The quote is the quote — no upcharges on the day.
The engineer arrives in branded uniform with photo ID. They confirm the diagnosis, fit the parts (usually 30–60 minutes), test the door at least a dozen times to confirm smooth operation, and walk you through the new keys. You pay by card, cash or bank transfer; itemised invoice is sent by email.
Workmanship is guaranteed for 12 months. Parts carry the manufacturer's standard warranty (typically 10 years for cylinders, 7 years for gearboxes). If anything goes wrong inside the guarantee window we come back free of charge.



