No premises or building or part thereof hereafter erected or altered wholly or partly in use or structure, or the open spaces pertaining to which are in any way reduced, shall be used until the Building Commissioner shall have certified on the building permit or, in case no permit is issued, shall have issued a certificate of occupancy, specifying the use to which the premises, or the building upon being sufficiently completed to comply with the provisions and regulations relating thereto, may be put.