20.28.110 Duplex/triplex/fourplex.
A. Description. A duplex/triplex/fourplex is a single structure comprised of two, three, or four dwelling units on a single lot, either side by side, on different floors, or a combination thereof.
B. Site Requirements and Setbacks. The required setbacks are as shown in Figure 20.28.110(A), except detached accessory buildings may be located in a rear yard and in the rear 22 feet of an interior side yard. Garages and carports shall be set back at least four feet from the street face of the residential building (excluding front porches). Buildings shall be placed within the shaded areas shown in the figure except as provided above.
C. Bulk and Massing.
1. Maximum floor area ratio (FAR) is 0.6.
2. The height limit is 25 feet under BMC 20.08.020, definition No. 1, or 20 feet under definition No. 2. The height may be increased to 35 feet under BMC 20.08.020, definition No. 1, when in residential-multi, multiple and commercial zoning designations.
Figure 20.28.110(A) Setbacks – Main Building
D. Usable Space, Open Space and Landscaping.
1. Each dwelling unit shall have 75 square feet of private usable space with no dimension less than five feet. No more than 50 square feet may be accommodated with a deck or porch.
2. Private usable space may be consolidated and provided as common usable space with minimum dimensions of 10 feet by 10 feet. All units shall have direct access to usable space.
3. No less than 30 percent of the site area shall be in open space consisting of landscaping or permeable material (may include permeable paving, landscape-based LID BMPs, and green roofs). Exceptions may be made in erosion hazard zones or areas with shallow bedrock as determined by the city.
4. A green factor landscaping score of 0.4 is required (see BMC 20.12.030).
E. Parking. All parking shall be provided pursuant to BMC 20.28.050(H).
F. Design Standards.
1. At least one entrance must be visible from the public street.
2. Ground level dwelling units that front the public street shall each have a covered front porch facing the public street. Said porches shall be no less than 40 square feet with no dimension less than five feet. A shared front porch entry no less than 60 square feet with no dimension less than five feet may be provided in lieu of private entries. Front porches are in addition to the private usable space requirement.
3. Garbage/recycling areas shall be consolidated, unless the local refuse provider approves otherwise, and screened from public view.
G. Design Guidelines. A duplex/triplex should be designed as either a larger, single-family composition or as distinct separate units.
1. Building Design.
a. The design should break the home’s facades into several distinct elements.
b. Roof forms that emphasize vertical proportions and create modulation are strongly encouraged.
Figure 20.28.110(C) Annotated Illustration of Duplex/Triplex
c. The massing should be varied with elements such as bays, dormers, etc.
d. A change of materials, colors or textures on building elements is encouraged to provide further articulation and additional variety and craftsmanship.
e. Buildings should minimize the impact of garages on the streetscape by utilizing garage doors with windows or other architectural features.
2. Site Design. Back yards should be designed for privacy from neighbors. [Ord. 2022-01-002 § 12; Ord. 2017-03-009 § 22; Ord. 2009-08-047].