1.   Except as hereinafter provided, no structure or premises shall hereafter be used, and no structure shall be extended, erected, converted, moved, rebuilt, or altered except in conformity with all the district regulations established by this chapter for the district in which it is or will be located and, if the cost or value of the construction or alteration is $500.00 or more, until a zoning permit has been secured from the Zoning Administrator as provided herein.

   2.   The principal use on a lot and the lot itself shall have access to a public street.

   3.   No structure in the rear of any principal building on the same interior lot shall be used for residence purposes.

   4.   Not more than one principal permitted use is permitted on an undivided quarter-quarter section of land or lot of record until the same has been subdivided according to the Code of Iowa and the ordinances of the City into a separate lot of record for each principal use. This requirement does not apply to farm dwellings provided for in the agricultural zoning district.

   5.   No lot shall hereafter be so reduced in size that any required yard or other open space, or lot width or area, will be smaller than is prescribed in this chapter for the district in which it is located.

   6.   No zoning lot in any residence district shall be hereafter platted or reduced in size so as to have a street frontage of less than 60 feet, except for “zero-lot line” development.

   7.   No yard or other open space on one lot shall be considered as providing a yard or open space for any other lot, and no yards or other open space about an existing structure or any structure hereafter constructed shall be considered as providing a yard or open space for any other structure.

   8.   If actual construction has been started on any structure pursuant to a permit at the effective date of this chapter, or any amendment thereto, nothing contained herein shall require any change in the plans, construction, or designated use of any structure or part thereof.

   9.   Every building hereafter erected, converted, moved, enlarged, or structurally altered shall be located on a zoning lot and there shall not be more than one principal building or use on one zoning lot, except that the Council may authorize more than one principal building or use on one lot after review and recommendation by the Commission.

   10.   One-family dwellings shall have a minimum gross floor area of 900 square feet per unit, except mobile homes may have a minimum of 720 square feet per unit.

   11.   Mobile homes shall be located only within mobile home parks (R-5 District) and in an Agricultural District.

   12.   Fences, walls, trees, and shrubs which interfere with traffic visibility shall not be permitted within vision clearance triangles, except in a B-1 District. Fences and walls not prohibited above are permitted in a required side or front yard provided such fence or wall, other than a retaining wall, shall not be higher than six feet, measured from ground level, unless any part above such height has at least 50 percent of the surface uniformly open and unobstructed; provided, however, that the 6-foot limitation does not apply to fences on or adjacent to side lot lines if the adjoining lot is not in a residential zoning district. Fences not prohibited above having a height of 10 feet or less measured from ground level may be located within a required yard.

   13.   No statuary, memorial, or work of art in a public place, and no public building, bridge, or public structure, shall be located or erected, or site therefor obtained, nor shall any permit be issued by any department of the City for the erection or location thereof, until the design and proposed location of any such improvement shall have been submitted to the Commission and its recommendations thereon obtained. Such requirement for recommendations shall not act as a stay upon action for any such improvement where the Commission, after 30 days’ written notice requesting such recommendations, shall have failed to file the same with the Council.

   14.   Any structure which has been damaged by fire, explosion, act of God, or the public enemy or left to deteriorate to the extent of more than 50 percent of its value, shall be restored, or the property shall be leveled to the grade as prescribed by the City within six months.

   15.   If construction of a structure is started and then abandoned for a period of two years, the property shall be returned to its original condition. If the property owner fails to comply with this subsection, the work will be done by the City and the cost shall be assessed to the property.

   16.   All minimum setback requirements shall be applicable to principal and accessory buildings and structures and no accessory building or structure shall occupy any part of a required yard, except for accessory buildings or structures in rear yards if and to the extent permitted under the applicable zoning district regulations.

   17.   All provisions contained in the definitions set forth in Section 165.05 of this chapter which are regulatory in nature are substantive and enforceable regulations under this chapter.

   18.   Except as provided in this subsection, the issuance of a zoning permit under this chapter for the construction of a new principal building or structure imposes on the owner of the lot for which the permit was issued a duty to repair, replace, or reconstruct any defective public sidewalks abutting said lot or, if no sidewalk exists, to construct public sidewalks abutting the lot, all in accordance with the regulations and standards of Chapter 136 of this Code. At the time the zoning permit is issued, the Zoning Administrator shall inspect any existing abutting sidewalks and shall inform the owner or the owner’s agent, in writing, of any sidewalk work required. The required sidewalk work shall be completed within one year after the zoning permit is issued and a Certificate of Compliance shall not be issued until the required sidewalk work is satisfactorily completed unless a waiver is granted. Upon the owner’s application, the Council may grant a renewable, five-year waiver of the requirements of this subsection for lots located in Agricultural A, Conservancy C, General Business B-2, and Manufacturing M-1 Zoning Districts if it reasonably appears that pedestrian traffic utilizing such sidewalks would be insignificant. The owner or any successor shall complete the required sidewalk work within one year from the expiration of such a temporary waiver. The Council may also grant permanent waivers of these requirements for any lot where topographical conditions render sidewalk construction unfeasible. The requirements of this subsection shall not apply to zoning permits issued for accessory buildings or for the alteration or enlargement of any building or structure.