Why Does My uPVC Door Catch or Stick at the Bottom?
6 min read
A front or back door that suddenly scrapes the frame, needs a shoulder to close, or only locks if you lift the handle hard is one of the most common problems we see. It's usually a simple adjustment — if it's caught early.
The most common cause: door drop
uPVC and composite doors are heavy, and they hang on just three hinges. Over months and years, that weight slowly pulls the door down and away from the hinge side. This is called door drop.
Once the door has dropped a few millimetres, the bottom corner on the lock side starts rubbing the threshold and the locking hooks no longer line up with the keeps on the frame.
Other reasons a door starts to stick
- Heat expansion — dark-coloured or south-facing doors swell in summer sun and can bind in hot weather
- Loose hinge screws pulling out of the frame
- Worn or misaligned keeps (the metal plates on the frame the locks engage with)
- A worn gearbox in the multi-point lock making the handle stiff
- Settlement in the building moving the frame itself slightly out of square
Why you shouldn't keep forcing it
When the hooks and rollers don't line up, lifting the handle puts huge strain on the gearbox inside the lock. Eventually something inside shears, and the handle goes floppy or the door won't lock — or won't unlock, leaving you shut out.
A door adjustment is a quick job. A snapped gearbox or a lock-out is a bigger one. If your door has started to catch, getting it adjusted now usually saves money.
How we fix it
Most sticking doors are sorted in a single visit:
- Hinges adjusted to lift the door and pull it back toward the hinge side
- Keeps re-aligned so the hooks and rollers engage smoothly
- Compression adjusted for a draught-free seal that's still easy to lock
- Gearbox or full multi-point lock replaced if it's already been damaged
Quick checks you can do yourself
Close the door and look at the gap around the edge — if it's wider at the top on the lock side than at the bottom, the door has dropped. Also check whether the handle is noticeably stiffer with the door shut than with it open; that points to alignment, not a faulty handle.
Need it fixed?
We cover Northampton, Northamptonshire and Milton Keynes. Free, no-obligation quotes.
Common questions
- Can a dropped uPVC door be adjusted?
- Yes. Most uPVC and composite door hinges are adjustable, so the door can be lifted and realigned without replacing anything.
- Why is my door only stiff in summer?
- uPVC expands in heat. A door that's already slightly out of alignment will bind when it swells on warm, sunny days.
- Do you offer free door adjustments?
- We offer free adjustments on single front and back doors in the NN4 area. See our free service page for details.