Door Hard to Lock in Cold Weather? Why and What to Do
Every winter we get calls from across Birmingham about doors that locked fine in summer but now need a shove, or won’t lock at all on frosty mornings. Usually the lock isn’t broken. The door has changed shape slightly with the cold.
Why it happens
uPVC and composite doors expand in warm weather and shrink in the cold. Even a millimetre or two is enough for the hooks and rollers to miss the keeps on the frame. Doors that face the weather, or get full sun in summer, move the most.
What you can safely do
- Push or pull the door gently into the frame while you lift the handle. If it then locks easily, it’s alignment.
- Spray a little silicone or PTFE spray on the moving locking parts along the door edge. Don’t use thick oil.
- If the key is stiff, a little graphite or PTFE spray in the cylinder can help. Don’t use cooking oil or WD-40 in the keyhole — it collects dirt.
What not to do
- Don’t keep forcing the handle. A stiff door puts extra load on the gearbox, and winter is when a lot of worn gearboxes finally break.
- Don’t pour hot water on a frozen lock. It can refreeze and make it worse.
When to call a locksmith
If you have to fight the door every morning, get it adjusted now, before the gearbox fails. A keep or hinge adjustment is a quick job and often fixes it all year round.
- Keep or hinge adjustment — quote by photo
- uPVC gearbox repair — from £99 plus parts
- 3-star anti-snap cylinder — from £69 plus parts
No call-out fee, and you get the price before any work starts.
Common Questions
Will it fix itself when it warms up?
It often gets easier in spring, but the strain on the gearbox doesn’t go away. An adjustment stops it coming back every winter.
Can I adjust it myself?
Some hinges can be adjusted with an Allen key — see our hinge guide. If you’re not sure, send us a photo and we’ll tell you what it needs.
My door won’t lock at all tonight. What should I do?
Don’t leave it unlocked. Call us 24/7 — we’re typically with you in around 30 minutes.
Need a Locksmith Right Now?
24/7, no call-out fee, typically with you in around 30 minutes.