155.9402. EXCEPTIONS AND VARIATIONS
   A.   Reduction of Minimum Lot Area or Width to Compatible Conditions 
      1.   If the average area or width of existing lots located on the same block face and in the same zoning district is less than applicable minimum lot area or minimum lot width (as appropriate) established in Article 3: Zoning Districts, the minimum lot area or minimum lot width (as appropriate) required of a lot shall be reduced to that average lot area or average lot width (as appropriate).
      2.   Properties within the RD and RM Zoning Districts may apply to exceed the zoning density to develop a Two-Family Dwelling, in the following instances, as decided by the Development Services Director:
         a.   the block face for the subject property is compatible with two-family development and the character of the block face is not single-family; and
         b.   compliance with the applicable development standards including but not limited to parking, landscaping, and dimensional standards; and
         c.   subject to the allocation of Reserve or Flexibility Units if required for compliance with the density as prescribed by the Land Use.
   B.   Maximum Height Exceptions
      Federally and State mandated height limitations such as Federal Aviation Administration (FAA) Height Restrictions, shall always apply; however, the maximum height limits established in Article 3: Zoning Districts, shall not apply to the following structures or structural elements:
      1.   Monuments, water towers, utility transmission towers, derricks, cooling towers, fire towers, parking garage shade structures, and other similar structures other than flagpoles not intended for human occupancy;
      2.   A parapet wall, cornice or other screening device may exceed maximum height limits to screen any mechanical equipment on the roof of a building from ground level, provided that the screening shall be erected only to a height necessary to screen the equipment.
      3.   Spires, belfries, cupolas, domes, chimneys, elevator shaft enclosures, ventilators, skylights, and similar rooftop structures or structural elements not intended for human occupancy, provided they comply with the standards in section 5. below;
      4.   Accessory Uses and Structures provided they comply with height limits established for the specific use in Section 155.4303, Standards for Specific Accessory Uses and Structures, provided they comply with the standards in section 5. below;
      5.   Structures and structural elements listed in 3. and 4. above must comply with the following:
         a.   Cover not more than 25 percent of the roof area of the structure to which they are attached;
         b.   Comply with applicable screening requirements for mechanical equipment and appurtenances in Section 155.5301, Screening; and
         c.   Extend above the applicable maximum height limit by no more than 25 percent of the height limit (unless otherwise allowed in this Code).
   C.   Allowable Required Yard Encroachments
Every part of every required yard shall remain open and unobstructed from the ground to the sky except as otherwise allowed in Table 155.9402.C, Allowable Required Yard Encroachments, or allowed or limited by provisions in Article 4: Use Standards, Article 5: Development Standards, or elsewhere in this Code.