Composite doors adjust at the hinges, in three directions. Height, side to side, and compression against the frame. Take the caps off the hinges, find the screw that moves the door the way you need, and turn it a quarter turn at a time. Close the door after every turn to see what changed.
Open your door and look at the hinge from the side. Composite doors hang on one of three types, and each one gives you a different set of adjustments.
Flag hinges give you all three directions, so a dropped door is straightforward. Butt hinges rarely offer height adjustment, which means a dropped door on butt hinges needs the keeps moved instead.
Take a photo of the hinge before you start. If you end up calling your installer, the photo answers their first question.
An Allen key set covers most composite hinges. Add a cross-head screwdriver, a flat-head for prising off the hinge caps, and a torch.
Bring a helper if the door is large or glazed. Composite slabs are heavy, and lifting the weight off a hinge while you turn a screw is a two-person job.
Work with the door closed for compression, and open for height and lateral movement. Then close it again and look. Adjusting a door you cannot see the gap on is guesswork.
Work one direction at a time, and change one hinge before you touch the next. Most doors need a quarter turn on a single hinge, not a full reset of all three.
The gap you are aiming for runs the same width from top to bottom along the closing edge. An even gap tells you the slab hangs square in the frame, and everything else gets easier from there.
Stop turning if a screw feels tight. Composite hinges strip, and a stripped hinge is a replacement rather than an adjustment.
A dropped composite door catches on the frame at the bottom of the closing edge, and the gap along the top widens towards the lock side. You will usually feel it before you see it, because the handle needs a lift to engage.
On flag hinges, raise the slab at the top hinge first. The top hinge carries most of the weight, and lifting there closes the gap without twisting the door.
On butt hinges, you have little or no height adjustment. Move the keeps on the frame down by a millimetre or two instead, which brings the lock points back in line with the hooks.
Check the hinge screws into the frame while you are there. A door that keeps dropping after every adjustment has a hinge working loose in the frame, and no amount of hinge adjustment fixes a loose fixing.
The hooks are missing the keeps, and nine times out of ten the door has moved rather than the lock failing. Open the door and look at the keeps on the frame. Scrape marks show you exactly where the hook is hitting and which way it needs to go.
Loosen the keep screws, move the keep a millimetre in the direction the marks point, then tighten and test. Small moves, one keep at a time.
If the handle lifts but the key will not turn, the door is pressing too hard against the frame. Back the compression off at the hinges and try again.
Never force the handle to make the hooks engage. The gearbox inside a multipoint lock is the most expensive part of the door, and forcing it is how it breaks.
Your door has bowed in the sun, and this is normal behaviour for a composite slab rather than a fault. Dark colours absorb more heat, so a dark grey or black door on a south facing wall moves most.
The tell is timing. A door that locks fine in the morning, fights you at four in the afternoon, and behaves again after sunset has bowed and recovered. Nothing is wrong with the hinges.
Do not adjust it out. If you set the compression to suit a bowed door at 4pm, the same door will rattle and let in draughts by October.
Wait for the evening and test it again. If the door still binds when the slab is cool, then it is worth adjusting.
Increase the compression, which pulls the slab harder against the weather seal. On flag hinges the compression screw sits on the face of the hinge. On butt hinges you may find a cam behind the cap, and if there is none, move the keeps inward instead.
Test it with a sheet of paper. Close the door on the paper and pull. Firm resistance without tearing is right, and you want the same resistance at the top, middle and bottom of the door.
Paper that pulls out freely at one corner means the door sits out of square. Sort the gap first, then set the compression.
Check the seal itself before you chase compression any further. Press the rubber with a finger. Soft and springy is healthy. Hard, flat or shiny means the seal has perished, and a perished seal needs replacing rather than squeezing harder.
Four things cause damage that adjustment cannot undo.
If the door has dropped so far that the slab rubs a groove into the frame, stop adjusting and call your installer. A worn frame face does not come back.
Three faults sit outside the reach of an Allen key, and all three look like an adjustment problem at first.
The frame sits out of square. Measure it corner to corner, both diagonals. A difference of more than a few millimetres means the frame moved or was fitted out of square, and the door is only reporting it.
The hinge has failed. Lift the closed door at the handle edge. Movement you can feel means play in the hinge itself, and worn hinges get replaced.
The slab has delaminated or swollen. Bubbling, a soft patch, or a skin lifting at an edge means water has reached the core. That is a replacement door, not an adjustment.
At that point the useful question changes from how to adjust it to what to replace it with. We make front doors in PVC, pine, meranti, alu-clad pine and alu-clad meranti, built to your measurements and delivered ready to fit.
