Title 17C Land Use Standards

Chapter 17C.110 Residential Zones

1. Purpose.
   The height standards promote a reasonable building scale and relationship of one residence to another and they promote privacy for neighboring properties. The standards contained in this section reflect the general building scale and placement of houses in the City's neighborhoods.
    

2. Height Standards.
   The maximum height standards for all structures are stated in Table 17C.110-3. The building height shall be measured using the following method:

   1. The height shall be measured at the exterior walls of the structure. Measurement shall be taken at each exterior wall from the existing grade or finished grade, whichever is lower, up to a plan essentially parallel to the existing or finished grade. For determining structure height, the exterior wall shall include a plane between the supporting members and between the roof and the ground. The vertical distance between the existing grade, or finished grade, if lower, and the parallel plan above it shall not exceed the maximum height of the zone.

   2. When finished grade is lower than existing grade, in order for an upper portion of an exterior wall to avoid being considered on the same vertical plan as a lower portion, it must be set back from the lower portion a distance equal to two times the difference between the existing and finished grade on the lower portion of the wall.

   3. Depressions such as window wells, stairwells for exits required by other codes, “barrier free” ramps on grade, and vehicle access driveways into garages shall be disregarded in determining structure height when in combination they comprise less than fifty percent of the facade on which they are located. In such cases, the grade for height measurement purposes shall be a line between the grades on either side of the depression.

   4. No part of the structure, other than those specifically exempted or excepted under the provisions of the zone, shall extend beyond the plan of the maximum height limit.

   5. Underground portions of the structure are not included in height calculations. The height of the structure shall be calculated from the point at which the sides meet the surface of the ground.

   6. For purposes of measure building height in residential zones, the following terms shall be interpreted as follows:

      1. “Grade” means the ground surface contour (see also “existing grade” and “finished grade”).

      2. “Fill” means material deposited, placed, pushed, pulled or transported to a place other than the place from which it originated.

      3. “Finished grade” means the grade upon completion of the fill or excavation.

      4. “Excavation” means the mechanical removal of earth material.

      5. “Existing grade” means the natural surface contour of a site, including minor adjustments to the surface of the site in preparation for construction.

    

   TABLE 17C.110.215-1 MAXIMUM HEIGHT
   Maximum Wall Height [1]	25 ft.
   Maximum Roof Height [2]	35 ft.
   [1] The height of the lowest point of the roof structure intersects with the outside plane of the wall. [2] The height of the ridge of the roof. See “Example A” below.

   Example A

3. Exceptions to the maximum height standard are stated below:

   1. Exceptions to the maximum structure height in the RMF and RHD zones are designated on the official zoning map by a dash and a height listed after the zone map symbol (i.e., CB-150). Changes to the height limits in the RMF and RHD zones require a rezone. Height limits are thirty feet, thirty-five feet, forty feet, fifty-five feet, seventy feet, or one hundred fifty feet depending on location.

   2. Buildings and structures over fifty feet in height must follow the design, setback and dimensional standards found in chapter 17C.250 SMC, Tall Building Standards

   3. Adjacent to Single-family and Two-family Residential Zones.
      To provide a gradual transition and enhance the compatibility between the more intensive commercial zones and adjacent single-family and two-family residential zones:
       

      1. for all development within one hundred fifty feet of any single-family or two-family residential zone the maximum building height is as follows:

         1. Starting at a height of thirty feet, the residential zone boundary additional building height may be added at a ratio of one to two (one foot of additional building height for every two feet of additional horizontal distance from the closest single-family or two-family residential zone). The building height transition requirement ends one hundred fifty feet from the single-family or two-family residential zone and then full building height allowed in the zone applies.
             

      
      
       

   4. Projections Allowed.
      Chimneys, flagpoles, satellite receiving dishes and other similar items with a width, depth or diameter of three feet or less may extend above the height limit, as long as they do not exceed three feet above the top of the highest point of the roof. If they are greater than three feet in width, depth or diameter, they are subject to the height limit.

   5. Farm Buildings.
      Farm buildings such as silos, elevators and barns are exempt from the height limit as long as they are set back from all lot lines at least one foot for every foot in height.

   6. Utility power poles and public safety facilities are exempt from the height limit.

   7. Radio and television antennas are subject to the height limit of the applicable zoning category.

   8. Wireless communication support towers are subject to the height requirements of chapter 17C.355 SMC, Wireless Communication Facilities.

   9. Uses approved as a conditional use may have building features such as a steeple or tower which extends above the height limit of the underlying zone. Such building features must set back from the side property line adjoining a lot in a residential zone a distance equal to the height of the building feature or one hundred fifty percent of the height limit of the underlying zone, whichever is lower.
       
4. Special Height Districts.
   Special height districts are established to control structure heights under particular circumstances such as preservation of public view or airport approaches. See chapter 17C.170 SMC, Special Height Overlay Districts.
    
5. Accessory Structures.
   The height of any accessory structure located in the rear yard, including those attached to the primary residence, is limited to twenty feet in height, except a detached ADU above a detached accessory structure may be built to twenty-three feet in height.

Date Passed: Monday, April 25, 2011

Effective Date: Friday, June 3, 2011

ORD C34717 Section 4