When any part of a wiring installation is to be concealed from view by the permanent placement of parts of the building, the person, firm or corporation installing the wiring shall notify the Building Inspector or his authorized deputy, and such parts of the wiring installation shall not be concealed until they have been inspected, provided that on large installations where the concealment of parts of the wiring proceeds continuously, the person, firm or corporation installing the wiring shall give the Building Inspector or his legal deputy due notice, and inspection shall be made periodically during the process of work.