Title 17C Land Use Standards
Chapter 17C.111 Residential Zones
Section 17C.111.230 Height
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.
Height Standards.
The maximum height standards for all structures are stated in Table 17C.111.205-2. The building height shall be measured using the following method (see Figure 17C.111.230-A):
Building height is the vertical distance from the average grade to the highest point of the roof or structure that is not listed as an exception to the maximum building height limits as listed in Section 17C.111.230(C).
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.
“Average grade” means the average of the ground level adjoining the building at all exterior walls. Where the ground level slopes away from the exterior walls, the reference point shall be established by the lowest points within the area between the building and the lot line or where the lot line is more than 6 feet from the building, use the reference point between the structure and a point 6 feet from the building.
Measurements shall be taken at the existing grade or finished grade, whichever is lower.
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.
Figure 17C.111.230-A Height Measurement
For purposes of measuring building height in residential zones, the following terms shall be interpreted as follows:
“Grade” means the ground surface contour (see also “existing grade” and “finished grade”).
“Fill” means material deposited, placed, pushed, pulled or transported to a place other than the place from which it originated.
“Finished grade” means the grade upon completion of the fill or excavation.
“Excavation” means the mechanical removal of earth material.
“Existing grade” means the natural surface contour of a site, including minor adjustments to the surface of the site in preparation for construction.
Exceptions to the maximum height standard are stated below:
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., RHD-150). Changes to the height limits in the RMF and RHD zones require a rezone. Height limits are forty feet, fifty-five feet, seventy-five feet, or one hundred fifty feet depending on location.
In the RMF and RHD zones, height does not include up to three feet of the above-grade portions of basement parking, where the elevation of the first residential finished floor is three feet or less above the lowest elevation of the existing grade or finished grade, whichever is lower. See Figure 17C.111.230-B.
Figure 17C.111.230-B: Basement Parking Excluded from Height
Buildings and structures over fifty feet in height must follow the design, setback and dimensional standards found in chapter 17C.250 SMC
Adjacent to R1 and R2 Zones.
To provide a gradual transition and enhance the compatibility between the more intensive commercial zones and adjacent R1 and R2 residential zones:
For all development within forty feet of any R1 or R2 residential zone the maximum building height is as follows:
Starting at a height of forty feet at R1 and R2 property boundaries, additional building height may be added at a ratio of 2 to 1 two feet of additional building height for every one foot of additional horizontal distance from the closest R1 or R2 zoned property.
The building height transition requirement ends forty feet from the R1 or R2 zoned property line and then full building height allowed in the zone applies.
Figure 17C.111.230-C: Height Transition
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.
In addition to the projections allowed under subsection (7) above, in the RMF and RHD zones, the following projections above the roof height are allowed:
Parapets and rooftop railings may extend four feet above the height limit.
Walls or fences located between individual rooftop decks may extend six feet above the height limit if the wall or fence is set back at least four feet from the edges of the roof.
Stairway enclosures that provide rooftop access and cumulatively cover no more than ten percent of the roof area may extend up to ten feet above the height limit, provided that the enclosures are setback at least fifteen feet from all roof edges on street facing facades.
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.
Utility power poles and public safety facilities are exempt from the height limit.
Radio and television antennas are subject to the height limit of the applicable zoning category.
Wireless communication support towers are subject to the height requirements of chapter 17C.355A SMC
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.
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.
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-five (25) feet in height.
Date Passed: Monday, August 12, 2024
Effective Date: Sunday, September 15, 2024
ORD C36555 Section 1
