The solarium door that will not lock in August

It is the middle of August. The solarium door locked perfectly at nine in the morning, and at seven in the evening the handle lifts, the key turns halfway and stops. By the following morning it works again. Nothing is broken, nothing was forced, and the door appears to be having opinions about the time of day.

It is not the lock. It is the metal.

Aluminium moves, and here it moves a lot

Aluminium expands roughly twice as much as steel for the same rise in temperature. A door leaf about two metres tall, sitting in direct afternoon sun, can easily be thirty or forty degrees hotter than it was at breakfast. That is enough to add a millimetre or two to its height and width.

A millimetre sounds like nothing. On a multipoint door it is everything, because the bolts have to line up with keeps machined into the frame with very little tolerance. The door grows, the frame grows at a different rate because it is shaded by the wall, and the two stop agreeing with each other by exactly enough to stop the mechanism throwing.

The doors this happens to in Torrevieja are almost always the same ones: solariums and west-facing terraces, above the roofline with nothing to shade them, on buildings with white walls that throw heat straight back at the frame.

What to do at the moment it happens

Do not force the handle. When a multipoint mechanism meets resistance and somebody applies a shoulder to the handle, what gives way is the gearbox inside the door edge. That turns a free adjustment into a part that has to be ordered by profile.

Try lifting or pulling the leaf. With one hand on the handle, lift the door slightly by the frame side, or pull it firmly towards you as you lift the handle. If it locks, you have confirmed the diagnosis: the door is out of line, not broken.

Wait for the temperature to drop. If it is not urgent, try again after sunset. A door that locks at ten at night and refuses at six in the evening is a heat and alignment problem, not a failing lock.

Shade it if you can. An awning or a toldo over a west-facing door is an unglamorous fix that works, and it makes the terrace usable in August at the same time.

What actually cures it

Most of these doors are adjustable, and the adjustment is what they need. Hinges on a hinged aluminium door have adjustment screws for height and for compression. Sliding doors have rollers that can be raised or lowered. The keeps in the frame can often be moved a little or have their strikers realigned so the bolts land where they should, hot or cold.

Done properly, the point of the job is to leave enough margin that the door works across the whole range from a February morning to an August evening, rather than being set perfectly for the day the technician happened to visit.

Where adjustment is not enough, it is usually because something has already been damaged by being forced: a bent bolt, a stripped gearbox, a hinge pulled out of the profile. Those are parts, and they have to match the door’s profile, which is why a photograph of the door edge with the handle lifted is the first thing to send.

Why it gets worse over the years

Two things stack up here. Sand and salt work into tracks and hinges, adding friction so the door needs more force to do the same job. And every summer of expansion and contraction loosens screws that were only just tight enough.

That is why these doors tend to fail suddenly after years of slowly getting stiffer. The heat is the trigger, but the margin had been disappearing for a long time before that.

If a door in your property is already being persuaded in the cool of the morning, deal with it before July. An adjustment in spring is a small job. The same door, jammed shut with guests on the terrace in August, is not.