uPVC Door Repair vs Replace Cost | The Real Ten-Year Maths
Replacing a uPVC door costs £800-£1,800. Servicing the gearbox and cylinder twice costs under £300. Here's the honest ten-year breakdown.
A uPVC door that won't lock properly feels like a crisis. A letting agent in Langley rings me on a Friday afternoon, tenant can't get out, viewings tomorrow. The instinct is to replace the whole door. It's shiny, it's new, it solves everything. It also costs between £800 and £1,800 fitted, and in most cases it was never necessary.
Here's what actually happens to a uPVC door over ten years, and what it costs if you spend the money sensibly.
What Goes Wrong and When
The door itself, the slab, the frame, the glass, rarely fails. What fails is the hardware inside it. Three things account for almost every call I attend in SL1 and SL2:
- The multipoint gearbox (the long mechanism running up the edge of the door) wears out or drops a cam. Brands like GU, Fuhr, Maco, and Mila are common on mid-range doors. A gearbox lasts roughly seven to twelve years with normal use.
- The cylinder gets worn, drags, or was never anti-snap to begin with. On a rental in Chalvey or Cippenham, the original cylinder is almost always the cheapest barrel the installer could source.
- The hinges sag. The door drops a few millimetres, the latch no longer aligns, and suddenly the whole mechanism feels broken when actually a £15 hinge adjustment sorts it.
None of those is a reason to buy a new door.
The Ten-Year Cost Table
| Scenario | Year 1 | Year 5 | Year 10 | Ten-Year Total |
|---|---|---|---|---|
| Replace door (mid-range, fitted) | £1,100 | £0 | £0 | £1,100 |
| Replace door (premium, fitted) | £1,700 | £0 | £0 | £1,700 |
| Service gearbox + upgrade cylinder | £180 | £0 | £0 | £180 |
| Service gearbox + upgrade cylinder x2 (years 1 and 7) | £180 | £0 | £180 | £360 |
| Hinge adjustment + cylinder upgrade only | £95 | £0 | £0 | £95 |
| Gearbox replacement (GU/Fuhr compatible) | £140 | £0 | £140 | £280 |
Prices reflect typical Slough call-outs including parts and labour. Cylinder upgrades in the table assume a TS007 3-star unit, an Ultion or Avocet ABS, which is what I'd fit regardless.
The maths isn't close. Twice in a decade, you service the door. You're still spending less than a quarter of a door replacement.
When Replacement Is Actually Right
I'll tell you when to replace, because sometimes you should.
If the frame has warped or cracked, usually from years of a sagging hinge grinding into it, repair gets expensive fast. Filler and reinstatement work rarely holds long-term on a uPVC frame under load.
If the glass unit has blown (condensation between the panes), you're either reglazeing that panel or replacing the door. Reglazeing a double-glazed unit in a standard door is £80 to £180 depending on size. That's still not a new door.
If the door is pre-2010 and has no modern multipoint lock, the gearbox options narrow. Some older Lockmaster or Winkhaus mechanisms aren't manufactured any more, and fabricating a workaround adds labour. At that point, a conversation about replacement makes sense.
And if a landlord in Britwell or Wexham is bringing a property up to standard before a new tenancy, PAS24-compliant doors do carry a measurable insurance and security benefit. That's a legitimate reason to spend the money, not just the door feeling stiff.
Where People Waste Money
The most common mistake is calling a window company rather than a locksmith for a door that won't lock. Window companies quote on replacement because that's what they sell. A locksmith looks at the gearbox, the cylinder, and the hinge alignment because those are the things that actually break.
I had a landlord in Colnbrook quote £1,400 for a new door on a property. The gearbox had dropped a cam on a GU Seceuroshield mechanism. New gearbox, compatible Fuhr replacement, new Avocet ABS cylinder. Ninety minutes on site, £165 total. Door's been fine since.
The second mistake is fitting a cheap replacement cylinder after a lockout. The door's open, you're relieved, the hardware shop on the Trading Estate sells a basic euro cylinder for £12. It goes in. Six months later it snaps in a break-in attempt, because Slough has a real problem with snapping attacks. Spend £40 to £60 on a TS007 3-star cylinder once and don't think about it again for a decade.
How to Spend the Money Sensibly
If the door is less than fifteen years old and the frame is sound, start with a service call. A locksmith will adjust the hinges, assess the gearbox, and tell you whether the mechanism needs replacing or just adjusting. Cost is usually £60 to £100 for the visit and adjustment alone.
If the gearbox does need replacing, budget £120 to £180 fitted. If you're already there, upgrade the cylinder to a 3-star anti-snap unit at the same time. You won't be back for years.
New door only if the frame has failed or the job stops making sense economically. That's a high bar. Most doors I see in SL1 and SL2 are nowhere near it.
uPVC or composite door repair
What is the door doing? Tick the closest, the engineer confirms on site.
A guide, not a quote. We give you the actual labour rate, an estimate on parts and the VAT on the call, then fix the price before any work starts. No anti-social hours surcharge.
Rapid Response covers Slough and all the SL postcodes, from Burnham and Iver through to Windsor and Datchet. Most calls we're on site in under thirty minutes. Pricing is quoted honestly on the phone before we arrive, not after.
Diane Norris, Security and standards specialist
Diane is the one who reads the test reports, and handles the survey work, the insurance questions and anything where the British Standard actually matters. Will happily explain why the number on the box is not the number that counts.
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