Method for repairing a wall structure and a wall element

A method for repairing a wall structure (202) of a sanitary unit of a cabin comprising at least an inner metal sheet (406) forming the wall surface of the sanitary unit, an outer metal sheet (402) and an insulator layer (404) between the inner and outer metal sheets, which method comprises at least the following steps

• removing the inner metal sheet (406) in such a way that installation frames formed on the inner metal sheet are left in the wall structure,
• removing the insulator layer (404) from a place where the inner metal sheet has been removed,
• installing a wall element (420) comprising a metal sheet (422), an insulator layer (424) attached to the metal sheet and fast connectors (432) for sanitary fixtures in the place of the removed wall structure in such a way that the edges of the metal sheet (422) of the wall element are placed overlappingly with the installation frames.