Trim structure for a door

A trim structure to accommodate a door, and to form a part of a partition, the trim structure comprises:

• two opposing lateral walls spaced apart by a thickness, said thickness being adjusted according to the thickness of the partition so that said lateral walls form an exterior surface that is flush with the exterior surface of the partition when the trim structure is assembled with the partition;
• a transverse end wall connecting the two lateral walls;
• said transverse end wall comprising a planar surface configured to border the thickness of a vertical edge face of the door and a projecting element forming a bearing surface for the door;
• said lateral walls being formed from at least one composite panel, said at least one composite panel comprising a central layer sandwiched between two layers of facing, wherein the lateral walls form a part of the partition;
• wherein opposing exterior surfaces of the lateral walls are coplanar with the partition.