The regulations specified in the Ordinance are subject to the following exceptions, modifications, and interpretations:

   1.   Interpretation. Whenever the regulations of the Ordinance require a greater width or size of yards, courts, or other open spaces, or require a greater percentage of the lot to be left unoccupied or impose other higher standards than are required in any other statutes or local ordinance or regulation, the provisions of the Ordinance shall govern. Whenever the provisions of any other statute or local ordinance or regulation require a greater width or size of yards, courts, or other open spaces, or require a greater percentage of the lot to be left unoccupied, or impose other higher standards than are required by the Ordinance, the provisions of such statute or local ordinance or regulation shall govern.

   2.   A legally established lot of official record which becomes nonconforming as a result of amendments to the Ordinance may be developed with structures or uses permitted within the district in which the lot is located subject to the following:

      A.   If a legally established lot of record is joined with another legally established lot of record or another parcel or portion thereof with which it was not historically transferred, or a legally established lot of record or portion thereof is divided from another legally established lot of record or another parcel with which it was historically transferred, it shall lose its status as a legally established lot of record unless the newly created parcel became nonconforming as a result of an amendment to the regulations in effect at the time the lot, parcel, or tract was created.

      B.   When a nonconforming lot can be used in conformity with all of the regulations applicable to the intended use, except that the lot is smaller than that required for the intended use, then the lot may be used as proposed just as if it were conforming.

      C.   In any district where dwellings are permitted, a single-family dwelling may be located on any legally established nonconforming lot irrespective of the lot area or width, provided however:

         (1)   The sum of the side yard widths of any such lot shall not be less than 30 percent of the width of the lot, but in no case less than 10 percent of the width of the lot for any one side yard.

         (2)   The depth of the rear yard of any such lot need not exceed 20 percent of the depth of the lot, but in no case shall be less than 20 feet.

   3.   Chimneys, cooling towers, elevator bulk-heads, fire towers, monuments, water towers, houses of worship, ornamental towers and spires, telephone, radio or television towers, or necessary mechanical appurtenances may be erected to a height in excess of existing district regulations of Story County; provided, however, no such structure shall be permitted to extend into the approach zones, clear zones, or other restricted air space required for the protection of any public airport.

   4.   No accessory building shall be erected in any required yard other than a rear yard, as provided hereinafter.

      A.   On a corner lot they shall conform to the setback regulations on the side road. Accessory structures may be erected as a part of the principal building, or may be connected thereto by a breeze-way or similar structure, provided all yard requirements for a principal building are complied with.

      B.   An accessory structure that is not a part of the main building shall not occupy more than 30 percent of the rear yard. No accessory structure shall be constructed upon a lot until the construction of the main building has actually commenced, and no accessory structure shall be used unless the main building on the lot is also being used.

      C.   In cases where the property is zoned A-1, Agricultural, an accessory structure may be constructed in advance of a dwelling, provided that construction of the dwelling begins within two years. A signed agreement between the Director and property owner is required by the applicant prior to construction.

   5.   Except as herein provided, every part of a required yard shall be open to the sky, unobstructed by a structure, except for the projection of sills, belt course, cornices, and ornamental features which are not to exceed 12 inches.

   6.   Open-lattice enclosed fire escapes, fireproof outside stairways, and balconies opening upon fire towers, and the ordinary projections of chimneys and flues into the rear yard may be permitted for a distance of not more than three and one-half feet and where the same are so placed as not to obstruct light and ventilation.

   7.   Covered stoops, uncovered stoops, unenclosed terraces, uncovered porches, platforms, and ornamental features which do not extend more than three feet above the floor level of the ground story may project into a required yard, and shall submit an application for zoning permit as required in Section 92.11, Required Permits. Projections shall maintain a distance of at least two feet from any abutting side lot line. Projections may extend not more than eight (8) feet into the required front setback and may extend up to fifty (50) percent of the required rear setback.

   8.   Temporary structures and uses that are used only in conjunction with construction work may be permitted in any district during the period of construction, but such temporary structures shall be removed upon completion of the construction work and shall submit an application for zoning permit as required in Section 92.11, Required Permits.

   9.   More than one industrial, commercial, multiple dwelling or institutional building or use may be established upon a single lot or tract in a district permitting these uses, provided that the yards and open spaces required around the boundaries of the lot or tract shall not be encroached upon by any such buildings, and provided further that there shall be no change in the intensity of use.

   10.   Where more than 40 percent of the frontage in a block has been built up with buildings having a front yard, then the building line of the building to be erected shall conform to the natural building lines of the block as determined by the existing buildings.

   11.   In instances where buildings are erected containing two or more uses housed vertically, the required side yards for the first floor use shall control.

   12.   Encroachment of ramps, elevators, mechanical access devices, and other structures intended to provide a reasonable accommodation that may be necessary, because of a disability, in compliance with the 2010 American Disability Act (ADA) Standards tor Accessible Design, are exempt from all bulk requirements of the applicable zoning district.

   13.   An accessory building may be built on an adjoining lot to the principle use, parcel, or tract if the adjoining lots, parcels or tracts are owned by the same property owner, and said property owner signs a Restrictive Covenant agreeing not to sever the adjoining lots, parcels, or tracts without the mutual consent of the Director and property owner.

   14.   Accessory structures which are less than 100 square feet and have no permanent attachment to the underlying ground shall not require a Zoning Permit; however, all bulk requirements of the applicable zoning district shall be satisfied with the exception of rear and side setbacks.

   15.   Where one parcel of property is divided into two or more portions by reason of different zoning district classifications, each of these portions shall be used independently of the others in its respective zoning classification for the determination of permitted uses and application of bulk standards.

   16.   Any pump, underground fuel storage tanks, and islands, including any canopies, shall be set back at least 20 feet from any street or lot line.

   1.   Statement of Intent. Within the various districts established by the Ordinance or by amendments that may later be adopted, there exist structures, use of land, use of structures, or use of land and structures in combination, which were lawful prior to the adoption of the Ordinance but which would be prohibited, regulated, or restricted under the provisions of the Ordinance. It is the intent of the Ordinance to permit these nonconformities to continue until they are removed, but not to encourage their survival. It is further the intent of the Ordinance that such nonconformities shall not be enlarged upon, expanded or extended.

   2.   Nonconforming Structures. Where a structure exists at the effective date of adoption or amendment of the Ordinance which could not be built under the terms of the Ordinance by reason of restrictions on area, lot coverage, height, yards, or other characteristic of the structure or its location on the lot, such structure may be continued so long as it remains otherwise lawful, subject to the following provisions:

      A.   Where an existing structure or structures or part or parts thereof are not in conformity with the Ordinance, no enlargement, alteration, or reconstruction shall be permitted which encroaches further into a required setback.

      B.   Should such structures be destroyed by any means to an extent of 60 percent or more of its fair market value at the time of destruction, exclusive of the foundation, it shall not be reconstructed except in conformity with the provisions of the Ordinance. If the structure is less than 60 percent destroyed above the foundation, it may be reconstructed provided that a zoning permit has been applied for within six months of such happening and reconstruction has been completed within the time frame specified in 92.11, Required Permits.

   3.   Nonconforming Use of Land. Where a use of land upon which no building or structure is erected or constructed exists at the effective date of adoption or amendment of the Ordinance that would not be allowed in the zoning district under the terms of the Ordinance, the use may be continued so long as it remains otherwise lawful, subject to the following provisions:

      A.   No such nonconforming use shall be enlarged or increased or extended to occupy a greater area of land than was occupied at the effective date of adoption or amendment of the Ordinance.

      B.   No such nonconforming use shall be moved in whole or in part to any other portion of the lot or parcel which was not occupied by such use at the effective date of adoption or amendment of the Ordinance.

      C.   If any such nonconforming use of land ceases for any reason for a period of more than six months, any subsequent use of such land shall conform to the district regulations of the zoning district in which such land is located.

      D.   The casual, intermittent, temporary, or illegal use of land shall not be sufficient to establish the existence of a nonconforming use and the existence of a nonconforming use on the part of a lot or tract shall not be construed to establish a nonconforming use on the entire lot or tract.

      E.   If no expansions occur, a nonconforming use of land may be changed to another nonconforming use of a similar nature within the same or a more restrictive zoning classification. Whenever a nonconforming use has been changed to a more restrictive zoning use or to a conforming use, such use shall not thereafter be changed to a less restrictive use.

   4.   Nonconforming Use of Structures. Where a use of a structure exists at the effective date of adoption or amendment of the Ordinance that would not be allowed in the zoning district under the terms of the Ordinance, the use may be continued so long as it remains otherwise lawful, subject to the following provisions:

      A.   No existing structure devoted entirely or in part to a use not permitted by the Ordinance in the zoning district in which it is located shall be enlarged, extended, reconstructed, moved or structurally altered except which required by law, unless the use is changed to a use permitted in the zoning district which such structure is located.

      B.   Any nonconforming use may be extended throughout any parts of a structure which were manifestly arranged or designed for such use at the time of adoption or amendment of the Ordinance. No such use shall be extended to occupy any land outside such building.

      C.   If no structural alterations are made, a nonconforming use of a structure may be changed to another nonconforming use of a similar nature within the same or a more restrictive zoning classification. Whenever a nonconforming use has been changed to a more restrictive zoning use or to a conforming use, such use shall not thereafter be changed to a less restrictive use.

      D.   Any nonconforming use of a structure which remains idle or unused for a continuous period of six months, whether or not the equipment or fixtures are removed, shall not again be used except in conformity with the regulations of the zoning district in which such structure is located.

      E.   The casual, intermittent, temporary, or illegal use of a structure shall not be sufficient to establish the existence of a nonconforming use and the existence of a nonconforming use on the part of a lot or tract shall not be construed to establish a nonconforming use on the entire lot or tract.

      F.   Any structure devoted to a use made nonconforming by the Ordinance that is destroyed by any means to an extent of sixty (60) percent or more of its fair market value at the time of destruction, exclusive of the foundation, then the right to maintain the nonconforming use shall expire and the structure shall not be reconstructed except in conformity with the regulations of the zoning district in which such structure is located. If the structure is less than sixty (60) percent destroyed above the foundation, it may be reconstructed and used as before provided that a zoning permit has applied for within six months of such happening and reconstruction has been completed within the time frame specified in 92.11, Required Permits.

   5.   Required Repairs. Nothing in the Ordinance shall be deemed to prevent the restoration to a safe condition of any building or part thereof declared to be unsafe by any official charged with protecting the public safety, upon order of such official.