the latch, handle, hinge or ordinary running hardware no longer lines up or operates normally. Repair an accepted accessible rail or fit a compatible running insert or replacement section without changing the building envelope.
Signs: the door sags, rubs, sticks or has uneven gaps around the opening or the door closes poorly despite an otherwise sound visible opening. Causes: normal wear in hinges, latches or compatible mechanical hardware or loose fixings, minor alignment drift or ordinary timber movement.
Some systems accept a repair insert, while others do not. The insert must suit the profile, roller contact and available clearance. An improvised cover can change the panel height or movement, so compatibility should be established before materials are purchased.
A replacement rail or insert needs the correct shape and dimensions. Provide the system reference where available. Similar-looking tracks may support different rollers, so a generic strip should not be assumed to be a suitable repair for every sliding door.
Keep the rail clear and check travel after the agreed work. Report recurrent catching so the remaining cause can be reviewed. Limits: Accessible non-structural running rails only. No threshold waterproofing alterations, drainage-system redesign, structural changes, major glazing or powered operators.