Most patio door faults come down to a few millimetres in the wrong place. Sliding doors adjust at the rollers or the glide rail along the bottom. Hinged patio doors adjust at the hinges and at the receiver on the frame. Work in quarter turns, and close the door after every change to see what moved.
"Patio door" means three different things in the UK, and each one adjusts somewhere else. Get this wrong and you will spend an afternoon turning screws that were never the problem.
Open your door and look at how the leaf moves. That tells you which row below you are in.
Sliding glass doors from us work on the lift-and-slide principle. Turning the handle down raises the leaf, and the door locks only when it sits closed and lowered with the handle turned up.
If your door came with our user guide, the operating section tells you which mechanism you have. Keep it to hand.
Three things cover almost every job on a patio door. A set of Allen keys, a cross-head and a flat-head screwdriver, and a torch for looking into the track.
Add a vacuum with a narrow nozzle if you have a sliding door. Grit in the channel causes more sticking than worn hardware does.
Work with the door open where you can, and close it after every adjustment. Adjusting blind is how a small misalignment turns into a big one.
One check before you start. If the door is new and the fault appeared within weeks of installation, contact us first. A settled door is yours to adjust. A brand new door that binds usually points to the fitting, and that is worth looking at properly.
Start with the track, because dirt causes most sticking. Leaf litter, sand and pet hair pack into the bottom channel and lift the leaf a millimetre off its running surface. The door then drags at one end and feels heavy at the handle.
Vacuum the whole channel, then wipe it dry with a cloth. Run the door two or three times and see what changed before you reach for a screwdriver.
Check the glide rail itself next. A dented or bowed rail will never run smoothly, and no amount of adjustment corrects a damaged one.
If the door still drags after a clean track, the leaf has dropped or the running gear has worn. That is when adjustment earns its place.
A dropped sliding door scrapes at one end of its travel, catches on the threshold, or leaves a widening gap along the top edge. On roller-based sliding doors, the fix sits at the bottom corners of the leaf.
Raise both corners by the same amount unless you are deliberately correcting a tilt. Lifting one end only puts the whole weight of the leaf on one roller, and it will fail.
If you run out of thread and the door still drags, stop. Either the rollers have worn out, or the frame itself has moved.
Hinged patio doors adjust in the same three directions as any other hinged door. Up and down, side to side, and in and out towards the frame. Find the direction the leaf needs to move, then turn the matching screw a quarter turn at a time.
On our terrace doors, the handle drives an espagnolette with three closing points. When the key turns hard or the handle needs both hands, the closing points are missing the receivers on the frame. The hinges were never the problem.
Look at the receivers with the door open. Scrape marks on the metal show you where the bolt is hitting and which way it needs to move.
Our own user guide gives the fix for this. Bend the tongue on the receiver inward or outward until the door closes firmly against the frame. That single adjustment solves both a stiff handle and a loose, rattling leaf.
Double patio doors carry a handle on the operating leaf only. The second leaf is held by flush bolts top and bottom, so check those are dropping fully into place before you adjust anything else.
Compression controls how hard the leaf presses against the weather stripping, and on a hinged patio door you set it at the receiver. Our user guide describes this as a seasonal job, because timber and PVC both move between summer and winter.
Here is the test that tells you when to stop. Close the door on a sheet of paper and pull. You want firm resistance without tearing, and the same resistance at the top, middle and bottom of the leaf.
Paper that slides free at one corner and grips at another means the door sits out of square. Fix that first, or you will chase the draught around the frame all afternoon.
Check the weather stripping while you are there. Run a finger along the rubber. Soft and flexible is healthy. Hard and shiny means it has perished, and a perished seal is a replacement job rather than an adjustment one.
Do not remove the weather stripping to get at anything. It sits in a groove around the sash and it belongs there.
The friction brake holds the leaf, and on our terrace doors it lets you park the door anywhere between 5° and 90°. Turn the handle of the open door to the closed position to lock it in place.
Two things matter here. Never pull the door shut while the handle sits in the locked position, because that loads the brake and the espagnolette in a direction they were not built for.
And accept the limit. No friction brake holds a door in strong wind, ours included. If your door blows shut on a gusty afternoon, that is the brake working as designed rather than a fault to adjust out.
Yes, once a year at minimum. Our maintenance guidance is to oil hinges, handles, espagnolette locks, slide bars, roller bolts and locks with an all-purpose oil.
There is one exception worth knowing, and most guides get it wrong. Keep the slide rails on friction brakes and concealed hardware clean, oil-free and free from paint. Oil on a friction brake stops it gripping, and then the door will not stay open at all.
So oil the lock and the hinges. Wipe the friction rail dry.
Some faults sit outside what a screwdriver reaches. Recognising them saves you an afternoon.
Check the frame diagonals with a tape measure if you suspect the frame. Corner to corner, both ways. More than a few millimetres of difference means the frame sits out of square, and the door is only telling you about it.
Adjusting the hardware yourself is normal maintenance, and our own product guide treats hardware adjustment and minor planing as finishing details rather than manufacturing defects. In other words, a seasonal receiver adjustment is not a warranty claim, and it is not something you need our permission for.
Two things do matter for cover. Our warranty excludes damage from incorrect installation, including units that are not fitted plumb and level with equal diagonals, and units fitted with foam alone. It also excludes damage from insufficient maintenance, which is why the annual lubrication is worth the ten minutes.
If a door develops a fault you cannot adjust out, and you believe it is a manufacturing or material defect, contact us rather than taking the hardware apart.
