The purpose of the Medium Density Residential R-4 Zones is to establish medium density housing opportunities within Millcreek which are consistent with the City's general plan for medium density residential areas within the City. It is the intent to balance neighborhood compatibility with the private property interests of those who wish to expand, develop, improve, or otherwise make exterior modification to their residential property.

This chapter applies to development in the Medium Density Residential (R-4) Zone. Development in the Medium Density Residential Zone may be subject to the requirements set forth in MKZ 18.61, Sensitive Lands.

Uses in the Medium Density Residential (R-4) Zones are allowed, either as permitted or conditional, and may include certain limitations as set forth in Table 18.38-1 Permitted and Conditional Uses in Medium Density Residential Zone. If a use is not explicitly designated in the table, then the use is prohibited. Use prohibitions or use limitations listed in Table 18.38-1 apply in addition to the general provision that uses not explicitly designated in the table are prohibited. An applicant seeking a Millcreek Business License may submit a Classification Request by following the procedure as set forth in MKZ 18.15.030 (J), to determine whether a proposed land use aligns with an existing land use listed in Table 18.38-1.

1. Setback Measurements. The minimum property size, width, setbacks, and maximum property coverage requirements are as determined by Table 18.38-2 Spatial Requirements for the Medium Density Residential (R-4) Zone and illustrated in Figure 18.38.1.
2. Side and Rear Setbacks for Civic and Institutional Uses. Civic and Institutional Uses require a minimum twenty-foot (20’) rear and side yard setback when abutting and sharing a property line with a residential use.
3. Side Yard Setbacks between attached units. The side yard setback between units within the same building and shared a common wall, may be reduced to zero feet.
4. A lot or parcel containing an existing legally-established two-household dwelling may be subdivided, subject to the standards as set forth in MKZ 18.26, Division of Legally-Established Two-Household Dwellings.

Figure 18.38.1 Spatial Requirements Diagram (letter labels related to Table 18.38-2)

1. Minimum Height. All dwellings shall be a minimum of one-story in height measured from original ground surface.
2. Maximum Height. Maximum building height is set forth in Table 18.38-3 Building Height and Building Envelope for the R-4 Zone.
3. Building Envelope. The height of structures may be further limited by the building envelope. The building envelope is formed by a box defined by the perimeter of the property line extended vertically perpendicular to the property line to a height and subsequent angle as set forth in Table 18.38-3. The entire building shall fit under this envelope except as described in the projections section below, and as illustrated in Figure 18.38.2.

Figure 18.38.2 Building Envelope

Building Height Envelope Projections. Dormers, gables, and non-habitable architectural elements may project beyond the building height envelope if they meet the following criteria, as illustrated in Figure 18.38.3:

1. Dormers:
   1. The width of the dormer shall not exceed 14 feet;
   2. Multiple dormers shall be spaced such that the distance to the edges of the roof is at least one-half the distance between dormers; and
   3. The dormer shall be no higher than the ridge of the roof.
2. Gables:
   1. The height of the gable is less than 1.75 times higher than the point where the graduated building height envelope intersects the gable;
   2. The height of the gable is less than the maximum building height; and
   3. The length of the gable comprises no more than 25 percent of the length of the building façade.

Figure 18.38.3 Dormer and Gable illustration with height envelope exception

The following may be erected on, or project into the required yard setbacks:

1. Fences and walls in conformance with this code and all other applicable rules and regulations.
2. Landscape elements, including trees, shrubs, and other plants.
3. Utility or irrigation equipment or facilities.
4. Decks, patios, porches, driveways, sidewalks, stairs, landings, not exceeding two feet (2’) above grade.
5. Covered porches and balconies may project up to 10 feet into the front yard or street side yard setback if they meet the following criteria:
   1. Porches or balconies shall remain unenclosed or “open style” without walls, doors, windows, or screens, except for the minimum required handrail.
   2. Porches and balconies shall not encroach into any easements or clear visibility at residential driveways and at street intersections.
   3. Porches, balconies, stairs, landings, eaves which project into the setbacks, shall not be located nearer than fifteen feet (15’) from a street property line, or project outside of the building height envelope.
6. Other architectural elements which are not used as habitable space.
   1. Cornices, eaves, sills, planter boxes, stairways, landings, awnings, window wells, or similar architectural features attached to the building and not enclosed by walls, extending not more than two feet (2') into a side yard or four feet (4’) into the front or rear yard. In no case shall a side yard setback be less than six feet (6’).
   2. Chimneys, fireplace keys, box or bay windows or cantilevered walls attached to the building, no greater than eight feet (8') wide, extending not more than two feet (2') into a side yard, or four feet (4') into a front or rear yard. In no case shall a side yard setback be less than six feet (6’).

To avoid a large, continuous building mass of uniform height; no portion of any building shall continue more than forty feet horizontally without a minimum of an eighteen-inch break in the roofline or introduction of a contrasting architectural element such as an overhang, projection, or inset of a minimum depth of two feet (2’) from the primary façade plane, to create shadow patterns along the elevation of the building.