Even though art murals are not signs, a building owner (or leaseholder with a right to possession of the wall upon which the art mural is to be placed) may at its option have the requirements and procedures of Article XXIX, Signs, apply to a proposed art mural that does not meet one or more requirements of this Article XXX, Art Murals. The building owner or leaseholder must notify the Department of Code Enforcement in writing that it wishes to utilize this option at least 45 days prior to installation of the art mural. The art mural will thereafter be subject to all of the requirements of, and procedures in, Article XXIX, Signs, instead of those in Article XXX, Art Murals.