A.    In the case of sidewalks, the provisions of this chapter relating to improvements shall only apply to property in residential use in blocks where the frontage of existing sidewalks, when added to the frontage of unimproved properties, constitutes more than fifty percent of the front footage of the block where the property is located; provided, further, the city council may, upon application of a property owner, affected by the provisions in this section, waive the requirements for installation of sidewalks because of unusual circumstances or hardship.

    B.    The term "block" as used in this section means property facing one side of any street between an intersecting street and the next intersecting street or between an intersection street and the end of a street which terminates in other than an intersection.  The term "unimproved property" means parcels of property not devoted by means of buildings or facilities to residential, commercial, or accessory uses. (Prior code § 21-14)