An ordinary hardware or alignment problem may be repairable without a new leaf. If replacement is appropriate, first confirm that the proposed external door suits the sound existing opening and exposure; a new leaf cannot remedy underlying frame or threshold defects.
Photograph the bottom clearance and threshold from inside and outside. An ordinary leaf fit retains the existing threshold arrangement. Changing drainage, waterproofing or the building opening is outside this task and should not be hidden inside a request to shorten the door.
A heavier replacement can demand different support from the original door. Identify the proposed material and weight where available. Fixing condition and hinge compatibility must be reviewed before hanging; ordinary replacement does not authorise reinforcement or structural modification of the opening.
Identify an authorised person who can remain available and explain any other access route. Keep pets and belongings away from the opening. Agree the handling and storage of the old leaf so a temporary opening does not create an unmanaged access problem.
Fit a suitable ordinary supplied leaf with agreed mechanical hardware and check closing, clearances and existing seal contact without altering the opening. Scope limits: Ordinary non-rated solid leaf replacement only. No structural opening work, glazing systems, fire-door certification, building-envelope alterations or specialist security work.