(3)   Maintenance Requirement.
The exterior of every historic building, structure, and object and of every building, structure, and object located within a historic district, and every public interior portion of a building or structure, shall be kept in good repair as shall the interior portions of such buildings, structures, and objects, neglect of which may cause or tend to cause the historic portion to deteriorate, decay, become damaged, or otherwise fall into a state of disrepair.