When plans contemplate the construction, building, fabrication, alteration, modification, structural change or renovation of any building or structure, in existence or to become in existence which shall be used for any industrial, commercial business, office or mercantile purpose, such plans shall be prepared by and bear the seal of a registered professional architect or engineer. A building permit may be issued only when such plans are accompanied by an affidavit of such registered professional architect or engineer stating that he has supervised the preparation of the plans and that to the best of his knowledge and belief the plans and specifications conform to this Building Code. (Ord. 84-2021. Passed 11-23-21.)