Building height limits and what can stick up above them

(a) All structures must fall within a building height envelope at a height specified by this chapter, or as specified on the zoning maps. Exceptions are specified under subsection (c), and other exceptions may be specified under special districts. (b) The building height envelope must run parallel to existing or finish grade, whichever is lower (see Figure 21-4.3 ), except where the finish grade is higher than existing grade in order to meet city construction standards for driveways, roadways, drainage, sewerage, and other infrastructure requirements, or to meet conditions of permits approved under this chapter. In these cases, height will be measured from finish grade. (c) The following structures and associated screening are exempt from zoning district height limits under the following specified restrictions: (1) Vent pipes, fans, roof access stairwells, and structures housing rooftop machinery, such as elevators and air conditioning, not to exceed 18 feet above the governing height limit; provided that structures housing rooftop machinery on single-unit, two-unit, and duplex-unit dwellings are not exempt from zoning district height limits; (2) Chimneys, that may also project into required height setbacks; (3) Safety railings not to exceed 42 inches above the governing height limit; (4) Utility poles and antennas. The council finds and declares that there is a significant public interest served in protecting and preserving the aesthetic beauty of the city. Further, the council finds that the indiscriminate and uncontrolled installation, location, and height of antennas are detrimental to the city’s appearance and image; may result in significant damage to the community’s sense of well-being, particularly in residential areas; and may have negative economic impacts to the city’s tourism industry, which relies heavily on the city’s physical appearance. However, the council also finds that there is a need for additional height for certain types of utility poles and antennas, and that there is a clear public interest served by ensuring that those transmissions and receptions providing the public with power and telecommunication services are unobstructed. Therefore, in accord with the health, safety, and aesthetic objectives set forth in § 21-1.20 , and considering the public interest needs associated with certain types of power and telecommunication services: (A) Utility poles and broadcasting antennas must not exceed 500 feet from existing grade. (B) Communication towers and communication support structures may not exceed 10 feet above the governing height limit; provided that in residential zoning districts where utility lines are predominantly located underground, the governing height limit will apply; and (C) Accessory receive only antennas may not exceed the governing height limit, except as provided under § 21-2.140-1 (i). (5) Spires, flagpoles, and smokestacks, not to exceed 350 feet from existing grade; (6) One antenna for an amateur radio station operation per zoning lot, not to exceed 90 feet above existing grade; (7) Wind energy generation facilities, where permitted; provided that each wind energy generation facility must be set back from all property lines pursuant to the standards in Article 5 ; (8) Any energy-savings equipment, including heat pumps and solar panels, not to exceed 5 feet above the governing height limit; provided that solar panels on buildings other than single-unit, two-unit, or duplex-unit dwellings may not exceed 12 feet above the governing height limit. The area underneath rooftop solar panels installed pursuant to this subdivision may not be enclosed and will not be counted as floor area; (9) Construction and improvements in certain flood hazard districts, as set forth in § 21-9.10 ; and (10) Agricultural structures in agricultural zoning districts, as set forth in Article 3 , Table 21-3.1 . (d) The following structures and associated screening may be placed on top of an existing building that is nonconforming with respect to height, under the following specified restrictions: (1) Any energy-savings equipment, including heat pumps and solar panels, not to exceed 5 feet above the height of the rooftop; provided that solar panels on buildings other than single-unit, two-unit, or duplex-unit dwellings may not exceed 12 feet above the height of the rooftop. The area underneath rooftop solar panels installed pursuant to this subdivision may not be enclosed and will not be counted as floor area; and (2) Safety railings not to exceed 42 inches above the height of the rooftop. FIGURE 21-4.3 HEIGHT MEASUREMENT