A dropping door, a stiff handle, a draught you can feel with your hand on a still day — most uPVC door problems fall into a small, predictable set of causes. Having seen these hundreds of times, the pattern is almost always the same: something has moved slightly out of alignment, and everything else is a symptom of that.
Key Takeaways
- Most uPVC door problems trace back to the door dropping or shifting slightly out of true, not a fault in the material itself.
- A stiff or hard-to-lift handle is an early warning sign, not something to force — forcing it is what breaks the gearbox.
- Draughts almost always come from the seals or the threshold, not from the uPVC slab itself failing.
- Basic hinge adjustment is genuinely a DIY job for most homeowners with the right Allen key.
- Most of these problems are cheap adjustments, not reasons to replace the door.
- Weather and temperature changes make existing misalignment more noticeable, they rarely cause it outright.
Why uPVC Doors Develop Problems Over Time
uPVC expands and contracts with temperature, more than most homeowners expect. A door that closes perfectly in spring can feel tight in a heatwave and loose again in winter. That movement is normal, but it exposes any weakness that was already there, particularly a door that wasn’t hung perfectly true when it was first fitted.
Regular use adds to this. Every open and close cycle puts a small load through the hinges and locking mechanism, and over years that gradually shifts the door’s position relative to the frame, even by a millimetre. That’s enough to change how the locking hooks meet the keeps, which is where most of the symptoms below start.
A Dropping Or Sticking Door
This is the most common complaint, and it’s almost always the hinges. As a door ages, the hinges can loosen slightly under the door’s own weight, causing the whole slab to drop a few millimetres on the hinge side. That’s enough to make the door catch on the frame or the floor, or make it noticeably harder to lock because the mechanism is no longer meeting the keeps squarely.
The fix in most cases is a hinge adjustment, not a new door. Flag hinges, the type fitted to almost all modern uPVC doors, have adjustment screws built in specifically for this.
A Stiff Or Hard-To-Lift Handle
A handle that’s suddenly stiff to lift is your door telling you it’s slightly out of alignment before anything actually breaks. When the door drops even a little, the locking hooks no longer line up cleanly with the keeps, and lifting the handle to engage them takes more force.
Do not force it. Forcing a stiff handle is the single most damaging thing a homeowner can do, because the pressure goes straight into the multi-point locking gearbox, a housing of small cast components and springs that can shatter under repeated force. Once that breaks, you can be left with a door that won’t lock properly, or one that’s jammed shut. A stiff handle caught early is a hinge adjustment; forced, it can become a gearbox replacement.
Draughts Around The Door
Draughts are almost never a sign the uPVC itself has failed. They come from the perimeter seals losing their compression over years of use and weather exposure, from a threshold that’s worn or blocked with debris, or from a letterbox without a proper brush or flap seal. A door that’s dropped slightly can also seal unevenly, tight at the top and gappy at the bottom, which feels exactly like a draughty door even though the seal material itself is fine.
Worn seals are inexpensive to replace and make a real difference. Before assuming the whole door needs replacing over a draught, check whether seals or alignment are the actual cause.
Door Swinging Shut Or Not Staying Open
If a door won’t stay open and swings shut on its own, that’s usually the hinges again, either loose or adjusted with a bias that pulls the door closed. Occasionally it’s confused with something else: a newer, better-sealed door can create a brief pressure change when it closes, which some homeowners describe as the house “shaking.” That’s an air pressure effect from a tighter seal, not a fault, and it’s worth ruling out before assuming the door is faulty.
DIY Hinge Adjustment: What You Can Actually Do
Most flag hinges allow three types of adjustment, each with its own Allen key size depending on the manufacturer: vertical (raising a dropped door back up), horizontal (pulling the door tighter against the seal), and compression (how firmly the door presses onto the seal). Small turns matter, a quarter turn at a time, checking the door after each one rather than making a large change at once.
This genuinely is a job most homeowners can do with the correct Allen key and a bit of patience. What isn’t a DIY job is gearbox replacement, which involves stripping the door edge and needs the right part for your specific hardware.
When It’s An Adjustment And When You Need A New Door
Nearly everything covered above is a repair, not a replacement decision. A door only genuinely needs replacing when the frame or slab has warped or cracked, when corner welds have failed, or when repairs keep recurring on the same door within a short space of time despite being done properly. For the fuller picture of when a fault crosses that line across all door materials, see common front door problems and when to replace yours.
Be wary of anyone who jumps straight to “you need a whole new door” over a stiff handle or a draught. In the vast majority of cases that’s simply not true, and it’s worth getting a second, honest opinion before spending money you don’t need to.
How To Prevent These Problems
Most of this comes back to how the door was fitted in the first place. A door hung correctly and level puts even, predictable load on its hinges and locking mechanism, and stays that way for years longer than one that started slightly out of true. We’ve covered this in full in why alignment and level matter in door installation, along with why proper sealing matters more than you think for the draught side of things. If draughts have already started creeping in, our guide to signs your door is letting heat out is a useful next read.
Frequently Asked Questions
Why has my uPVC door started sticking or dropping?
Almost always the hinges, either loosening slightly under the door’s weight or needing adjustment after seasonal expansion and contraction. It’s rarely a sign the door itself has failed.
Why is my uPVC door handle stiff to lift?
The door has likely dropped or shifted slightly, so the locking hooks no longer meet the frame keeps cleanly. Get it adjusted rather than forcing the handle, which risks breaking the internal gearbox.
Why is my uPVC door letting in draughts?
Usually worn perimeter seals, a blocked or worn threshold, or a door that’s dropped and is no longer sealing evenly all the way round.
Can uPVC door problems be fixed without replacing the whole door?
In the great majority of cases, yes. Hinge adjustment, seal replacement and gearbox replacement all cost a fraction of a new door and resolve the vast majority of common complaints.
How much does it cost to fix a uPVC door in the UK?
It depends on the fault and the parts needed, so treat any figure quoted without seeing the door as an estimate. A hinge adjustment is generally inexpensive; a gearbox replacement costs more but is still well below the price of a new door.
Why do uPVC doors play up more in summer or winter?
Temperature swings make uPVC expand and contract, which exaggerates any misalignment that’s already there. A door that’s borderline in mild weather can tip into sticking or a stiff handle at the extremes of hot or cold.
Get The Diagnosis Right Before You Spend
Nearly every common uPVC door problem is a symptom of small misalignment, and nearly every one of them is fixable without replacing the door. Get the actual cause identified, whether that’s hinges, seals or the gearbox, before agreeing to anything more expensive than it needs to be. If a door genuinely is past saving, our uPVC doors page is a sensible next stop.