The sign area of window signs, permanent and temporary, shall not exceed fifteen (15) percent of the window area of the building premises or three hundred (300) square feet, whichever is less. Subject to the window area limitation herein specified, temporary window signs may be in addition to the signs otherwise permitted on the premises. For the purpose of determining allowable sign area on any premises, permanent window signs shall be treated as wall signs. (Ord. 7120-NS § 8 (part), 2009)