The short answer
A front door that will not latch has lost alignment between the latch or lock bolts and the keep plate in the frame. Composite and uPVC doors drop on their hinges, expand in heat and settle with the frame, so the bolts no longer line up with the holes they were fitted to.
What is actually happening
A multipoint lock on a composite or uPVC door throws several bolts into keeps along the frame. Every one of those has to line up within a millimetre or two. If the door has dropped, or the frame has moved, the bolts hit the keep instead of entering it — so you lift the handle and it will not go.
The tell-tale is the shove. If you have to pull, lean or lift the door to get the handle up, you are already forcing the mechanism, and the gearbox inside the lock is taking the load every time.
The usual causes
Front door latch failures come down to a short list:
- Hinge drop. Heavy composite doors sag over time, especially on three-hinge sets that have never been adjusted since installation.
- Thermal expansion. Dark composite doors in direct sun can expand and bow measurably. Doors that only stick on hot afternoons are almost always this.
- Frame movement. Settlement, or fixings into packers rather than the structural opening, lets the frame flex when the door is closed.
- Worn keeps and strike plates. Years of the bolt scraping the edge of the keep wears a lip that eventually blocks it.
- Failing gearbox. Once a lock has been forced for months, the internal gearbox wears out and the handle goes slack or stiff regardless of alignment.
- Compressed or perished weather seals. A seal that has gone hard changes how far the door closes into the frame.
Why this one should not be left
A misaligned front door is a security issue, not just an annoyance. If the bolts are only partly entering the keeps, the door is far easier to force than it looks — and many home insurance policies expect locks to be in working order.
It also escalates. Forcing a handle wears the gearbox, and a failed gearbox typically means replacing the whole multipoint strip rather than making a hinge adjustment. Sorting the alignment early is normally the difference between a small job and a lock replacement.
What we look at
The order matters: check whether the door is square in the frame, whether the frame itself is true, then whether the keeps have worn, and only then whether the mechanism has failed. Adjusting keeps to chase a hinge problem just moves the fault along the door.
How we put it right
Front door latch alignment, from £65
Hinge, keep and frame checked as a set so the door closes and locks without being forced.
Serving Leamington Spa, Warwick, Kenilworth, Whitnash, Cubbington, Southam and surrounding Warwickshire.
Common questions
Why is my composite door hard to lock in hot weather only?
Composite doors absorb heat and expand, particularly dark colours on a south-facing elevation. The door grows into an opening that fits it in cooler weather. It needs setting up so it works across the full temperature range rather than being adjusted to one season.
Should I just squirt lubricant into the lock?
Lubricant helps a dry cylinder, but it does nothing for a door that has dropped, and general-purpose sprays can attract grit inside a multipoint mechanism. If the door needs lifting to lock, the problem is alignment, not friction.
How much is a front door alignment?
Front door latch alignment starts from £65. If the gearbox has already failed, the mechanism cost is quoted separately once we have identified the model.