A. Purpose. These standards implement the goals and policies of the Mountlake Terrace Comprehensive Plan Vision 2044. Vibrant, inclusive and healthy residential neighborhoods are often made up of a variety of housing types that provide different physical configurations to meet a variety of living preferences, family sizes and budgets. Middle housing (housing types that include more than one attached or detached units on a lot) is compatible with existing residential neighborhoods, and can promote pedestrian access, building orientation to the street, and minimize the impacts of vehicular access. This chapter defines general design standards applicable to all development, as well as design standards specific to five defined housing form types to provide both the predictability and variety of successful middle housing neighborhoods. (Ord. 2885 § 2 (Exh. A), 2025).

A. Applicability. This chapter applies to all parcels within residential districts, and is intended to work alongside the development standards in Chapter 19.30 MTMC , R – Residential Districts.

1. Exception for Existing Development. Legally existing multiple-household buildings are not required to meet the design standards for multifamily development, except when the building is being enlarged in footprint, height, number of dwelling units, or any other manner or when the building is being reconstructed pursuant to MTMC 19.120.250(I)(1), as now or hereafter amended.

B. Design Review. The process used for reviewing compliance with these design standards shall be administrative design review as part of the permitting process. (Ord. 2885 § 2 (Exh. A), 2025).

The following standards apply to all development in the residential districts. In cases where housing form type standards in MTMC 19.32.060 conflict with general standards in this section, the housing form type standard shall prevail.

A. Building Orientation and Access.

1. Primary Elevations and Primary Entries. All buildings abutting a street shall have a primary elevation (including a primary entrance) that orients to the abutting street or right-of-way. Front setbacks are calculated to this primary elevation. Building width and ground floor use percentages are measured along this elevation.

2. Other Elevations and Entries. Buildings and dwelling unit entries not abutting streets must orient to a common open space, midblock connection, or improved parking court. See more detail in MTMC 19.32.060, housing types.

3. Prohibited Primary Elevation Elements. Primary elevation and all street-facing facades shall not contain elements commonly associated with a rear elevation appearance, such as utility meters, refuse containers, and loading or storage areas.

4. Pedestrian Paths. All shared building entrances and all primary dwelling unit entrances on a lot must be accessible via pedestrian paths from the public sidewalks or a midblock connection if it exists. Pedestrian paths must be at least five feet wide and may be shared with vehicular driveways on lots with eight or fewer dwelling units. Pedestrian paths which cross in front of dwelling units should be set back at least three feet from portions of adjacent facades that contain windows or entries to those units.

Figure 19.32.020.A. Examples of primary elevations. The image on the left shows a primary elevation oriented to the street with clear pedestrian access to the main entry. The image on the right shows a primary elevation that is not oriented to the street, with no clear access to the main entry and minimal orientation of windows or other facade elements towards the street. Image Credits: City of Portland, Kevin J. Beaty/Denverite.

B. Ground Floor Uses.

1. Required Habitable Space. Ground floors of primary elevations shall have a minimum width of 50 percent of the linear frontage of habitable space for a depth of 10 feet.

Figure 19.32.020.B1. Examples of habitable space and garage percentages. Image Credits: Zillow.

2. Vertical Location. The finished floor of a ground floor habitable space must be at sidewalk grade or up to five feet above sidewalk grade elevation, unless site conditions prohibit such a relationship. This is to allow garages or other utility spaces to be located partially underground along the street frontage without counting against habitable space requirements. It also discourages privacy issues when habitable spaces are located below sidewalk grade.

Figure 19.32.020.B2. Examples of elevated ground floors to allow partially below-grade garages that do not count against habitable space requirements. Image Credits: Zillow.

3. Garage Design. Individual garages that are separated by less than four feet of facade width shall be considered one garage for the purposes of establishing setback requirements. Garage doors shall be set back from the primary elevation or roofed porches by the following:

a. Garages less than 12 feet wide: set back two feet.

b. Garages 12 feet wide or greater: set back four feet.

C. Facade Materials.

1. Selection of Materials. Facades must support Mountlake Terrace’s identity and goals to be a high quality and sustainable community. Materials must be durable, low maintenance, and resistant to wear and vandalism, selected and designed for a 50-year life span (minimum 20 years for roofs).

2. Imitation stone, imitation brick (non clay-based), stucco, or exterior insulation finish systems (EIFS) may only be allowed on any building elevation if samples are approved during the permitting process.

D. Modulation and Articulation.

1. Purpose. Modulation can break down overall building mass to reinforce the residential scale of Mountlake Terrace’s neighborhoods, and articulation can provide human-scaled detail that makes a new development more compatible with existing houses and creates visual interest for pedestrians to promote walkability.

2. Applicability. Modulation and/or articulation features, selected from subsections (D)(3) and (D)(4) of this section, are required on street facing elevations based on their dimensions in this section. Deviations that propose a comparable alternative to the modulation or articulation items on these lists will be considered during the administrative design review process.

a. Facades From 40 Feet to 80 Feet Wide. A minimum of two modulation features, or one modulation feature plus one articulation feature.

b. Facades Over 80 Feet Wide. A minimum of two modulation features plus one articulation feature, or one modulation feature plus two articulation features.

c. Exceptions. The following building types may replace all required modulation features with articulation features: affordable housing; new construction or retrofits of buildings meeting passive house requirements; conversion of existing buildings to housing or mixed-use development that includes housing; modular construction; or mass timber construction.

3. Building Mass Modulation Features. This subsection lists the modulation features that may be used to meet the requirements of subsection (D)(2) of this section. Designers must avoid excessive modulation that does not respond to one of the following conditions:

a. Expressing individual units through facade plane shifts of at least two feet.

b. Step backs or insets to provide outdoor terraces at least five feet deep.

c. Insets at rooms or entrances at least two feet deep.

d. Projected rooms or bay windows at least two feet deep and five feet wide.

Figure 19.32.020.D1. Examples of compliant building mass modulation, including expression of individual units, step backs at terraces, insets at entry, and projected bay window. Image Credits: Davis Studio, Gravity Architecture, Redfin, Lexington Window Replacement.

4. Facade Articulation Features. This section lists the articulation features that may be used to meet the requirements of subsection (D)(2) of this section. Designers must avoid excessive articulation that does not respond to one of the following conditions:

a. Identifying primary entrances with a change of material, architectural millwork or brick detail, and/or integrated signage.

b. Repeating facade elements at least every 20 feet, such as: balconies at least four feet deep; Juliette balconies at least six inches deep; shading devices at least two feet deep; stoops at least three feet above sidewalk grade to individual units; porches at least five feet deep; bay windows at least two feet deep; or distinct window combinations per subsection (D)(4)(c) of this section.

c. Combining or emphasizing windows using a change of material or color from the primary facade.

d. Change of cladding materials or patterns, such as changing the materials at a building’s base to contrast and complement its top, at the top to contrast and complement its base, or to differentiate units. Changes in cladding materials, colors, or patterns are limited to three per facade, exclusive of accent colors for windows and balconies.

e. Windows with deep, detailed frames. May include windows recessed at least two and one-half inches from the cladding material, deep metal “flashing” surrounds at least two inches proud of the cladding material, or decorative window trim at least two inches wide.

f. Face brick with a nominal two-inch depth used as a cladding material on at least 75 percent of the facade. “Thin brick” less than two inches in depth does not comply with this articulation option (but is not prohibited as a cladding material).

g. Expressing roof forms, including sloping forms such as gables or shed roofs, stepping back or forward at least 12 inches, a strong cornice line of at least 12 inches high or eight inches deep, or an overhang of at least 12 inches.

Figure 19.32.020.D2. Seven examples of compliant articulation. Image credits: Grow Community, Hybrid, Weinstein AU, YR Architecture Design, Mithun, Micheal Hsu OofA.

Figure 19.32.020.D3. Example of too much modulation and too much articulation. Image Credits: Redfin.

E. Transparency, Windows and Openings.

1. Required Transparency. Primary elevations shall include windows comprising at least 25 percent of the facade and a minimum of eight square feet. On a corner or through lot, any other facade of the home that abuts a street shall include at least eight square feet of glass area in windows and/or doors. Any structure with a facade greater than 15 feet in width that is visible from the street shall include windows in a total amount of at least eight square feet on the visible facade.

2. Visual Privacy. Placement of windows on facades facing units on the same lot shall create appropriate levels of privacy between units through placement of windows and landscape buffers or other screening techniques. Facades within 10 feet of facades on the same lot may not overlap facing windows by more than 50 percent.

3. Prohibited Blank Walls. Blank walls on the first story more than 20 feet in width are prohibited abutting a public street or right-of-way. These walls shall use a combination of modulation, windows, openings, and/or landscaping to achieve a required visual break of at least one foot in width. Stored merchandise, pipes, conduit, utility boxes, air vents, and/or similar equipment do not count toward this requirement.

F. Primary Entries.

1. Covered Entries. Covered entries are required for all primary entries to buildings and individual dwelling units. They are not required for additional entries to individual dwelling units, such as side doors or back doors. Covered entries may include: porches, canopies, alcoves beneath upper story overhangs, and other elements or combinations that protect pedestrians from the weather. All dwelling units shall have a covered entry with a minimum depth of three feet and a minimum total area as follows:

a. Single unit entry: 20 square feet minimum.

b. Shared entry: 30 square feet minimum.

2. Addressing. All unit and accessory dwelling entries must have clear addressing visible from the street. If a unit entry is not visible from the street, an address and some form of directional notation must be placed along a walkway, on a fence, on the main house, or in some location that differentiates the front unit address from the rear unit address and is visible from the main access point to the lot.

Figure 19.32.020.F. Examples of covered entries, including modern canopies and traditional porches. Image Credits: Gravity Architecture, Zillow.

G. Required Open Space.

1. Common Open Space. This includes spaces such as yards, patios, courtyards, decks, community gardens, children’s play areas, or other multi-purpose outdoor recreational and/or green spaces, or a combination. Requirements include the following:

a. No dimension shall be less than 15 feet.

b. Must be positioned near or include a shared path, shared building entry, or other pedestrian activity to allow access from all units on a lot.

c. Must feature paths, appropriate hard surfacing, landscaping, seating, lighting and other pedestrian amenities to make the area functional and enjoyable.

d. Must be oriented to receive direct sunlight for part of the day, facing east, west, or (preferably) south, when possible.

e. Must be open to the sky, except a maximum of 25 percent of the common open space may be covered but not enclosed by porches, gazebos, pergolas, or other such structures, provided no dimension is less than eight feet.

f. May not include or be divided by driveways or parking spaces for vehicular use.

2. Private Open Space. This includes spaces, such as yards, patios, gardens, terraces, and decks, or a combination. Requirements include the following:

a. Minimum Dimensions.

i. At grade or roof decks: No dimension shall be less than six feet.

ii. Above-grade balconies: No dimension shall be less than four feet, and no area less than 30 square feet.

b. Must be directly accessible from the dwelling unit.

c. If provided, common open space meeting the requirements of subsection (G)(1) of this section may replace an equal amount of private open space.

3. Landscaping. Thirty-five percent of at-grade open space must be comprised of landscaping.

4. Vehicular access areas shall not count as open space.

H. Utilities and Solid Waste.

1. Waste Enclosures. All waste receptacles, including trash, recycling, and composting containers, must be stored in a waste enclosure. Waste enclosures must be designed to minimize their appearance and enclosed to screen waste containers from view. Waste enclosures may be no more than four feet in height. Sides of enclosures more than six linear feet in length should utilize one of the following:

a. Cedar, pressure treated lumber or other fencing materials.

b. Matching facade materials to residential buildings on site.

c. Landscape screening.

2. Waste Enclosure Location. Waste enclosures shall not be located along primary elevations. On lots with five or fewer dwelling units, they may be sited in individual locations for each unit, such as in garages. Waste enclosures on lots with six or more dwelling units shall be located in centralized common waste enclosures. Common waste enclosures must be located to facilitate efficient waste pick-up.

Figure 19.32.020.H1. Example of shared solid waste enclosure. Image Credits: Hybrid.

3. Utilities. Utilities, including meters, utility covers, and transformers shall not be located on primary elevations and must be screened from view from the abutting street. All utility equipment shall be located out of the pedestrian path of travel. In conditions where it is not possible to avoid placement on a primary elevation, utilities shall be located and designed to be integrated into the building facade through techniques that may include:

a. Locating within a notch or recess of the building wall;

b. Landscape screening to hide from public view;

c. Locating on a facade that is not intended to have direct pedestrian access.

Figure 19.32.020.H2. Example to avoid, showing small side yard pedestrian access in a Slot development being made inaccessible by retaining wall and placement of utility meters. Source: Mithun.

(Ord. 2885 § 2 (Exh. A), 2025).

A. Applicability. In accordance with the Comprehensive Plan Vision 2044, a variety of “middle housing” types are allowed to be built in the residential districts, with the goal of providing different building, yard, and dwelling unit configurations to meet a variety of living preferences, family sizes, budgets, and ownership models. This section defines design standards specific to five defined housing form types to provide both the predictability and variety of successful middle housing neighborhoods. They include: singles, slots, rows, stacks, and courts.

1. Permitting. When applying for a permit, the applicant must indicate which housing form type is proposed, and must comply with that type’s unique design standards in this section.

2. Combining Types. Multiple buildings and different form types may be combined on a site, especially on large sites. When combining housing form types on a site, the applicable design standards will be applied individually to each portion of the site as appropriate.

B. Singles.

1. Description. Singles refer to buildings containing one dwelling unit, detached from any other buildings or dwelling units by more than three feet. They may be located abutting streets and in back yards. Each single has a private entry. Examples of building types that could be classified as singles include single-unit homes, backyard cottages, and detached accessory dwelling units.

2. Maximum building width and depth: 60 feet width, 75 feet depth.

3. Building Orientation and Access. Primary elevation shall orient to street where one exists, including singles located in the rear yard on a corner lot. Singles located in rear yards may orient to street, shared yard, midblock connection, or alley if present.

Figure 19.32.060.B. Examples of Singles. Image Credits: City of Florence, Davis Studio Architecture + Design, Our Town St. Helena, Zillow.

C. Slots.

1. Description. Slots refer to buildings with attached single- or multi-story dwelling units aligned perpendicular to the street. The units are configured side-by-side. Each dwelling unit has a private entry. A shared driveway is often included for parking and/or garage access. Examples of building types that could be classified as slots include townhomes, duplexes, triplexes, fourplexes, fiveplexes, sixplexes, and attached accessory dwelling units.

2. Maximum Building Width and Depth. For the purposes of calculating maximum building width and depth, a cluster of attached dwellings is measured as one building.

a. R-1: 60 feet width, 90 feet depth.

b. R-2: 60 feet width, 100 feet depth.

c. R-3: 60 feet width, 130 feet depth.

d. R-4: 60 feet width, 140 feet depth.

3. Building Orientation and Access. Dwelling units abutting a street shall orient to that street. Additional units shall orient to a primary pedestrian access path.

4. Articulation. Buildings shall be articulated to emphasize individual units.

5. Street Orientation Incentive. Front setbacks may be reduced by three feet if at least two units per 50 feet of linear street frontage orient to that street.

Figure 19.32.060.C. Examples of Slots. Image Credits: b9 Architects, Google Maps, City of Portland.

D. Rows.

1. Description. Rows refer to buildings with attached single- or multi-story dwelling units aligned parallel to the street. Dwelling units are configured side-by-side and may be located abutting the street and in a backyard. Each dwelling unit has a private entry. Townhouses are the most common example of rows, but other examples include duplexes, triplexes, fourplexes, fiveplexes, sixplexes, and attached accessory dwelling units.

2. Maximum Building Width. For the purposes of calculating maximum building width, a cluster of attached dwelling units is measured as one building.

a. R-1: 90 feet width.

b. R-2: 100 feet width.

c. R-3: 130 feet width.

d. R-4: 140 feet width.

3. Building Orientation and Access.

a. Units abutting one or more streets shall orient to the longest street frontage. Dwelling units in backyards shall orient to the primary pedestrian access path or shared pedestrian-vehicular path or improved parking court.

4. Articulation. Buildings shall be articulated to emphasize individual units.

5. Shared Parking Area Incentive. A single driveway accessing a shared parking area for front and rear dwelling unit parking is encouraged. A front setback reduction per Table 19.30.030 is available to fit this parking area on the lot.

Figure 19.32.060.D. Examples of Rows. Image Credits: Zolo, Redfin.

E. Stacks.

1. Description. Stacks refer to buildings with attached dwelling units that stack on top of each other. Dwelling units usually have a shared entry but may also have private entries. Examples of stacks include stacked flats, duplexes, triplexes, fourplexes, fiveplexes, sixplexes, multiplexes, and small apartment buildings or condominiums.

2. Maximum Building Width and Depth.

a. R-1 and R-2: 75 feet width, 120 feet depth.

b. R-3: 130 feet width, 130 feet depth.

c. R-4: 140 feet width, 140 feet depth.

3. Articulation. Primary shared entrances must be emphasized with building articulation techniques such as those described in MTMC 19.32.020(D).

Figure 19.32.060.E. Examples of Stacks. Image Credits: Zillow, The Albertan, Redfin, Hybrid Architecture.

F. Courts.

1. Description. Courts refer to attached or detached dwelling units arranged around a courtyard or shared common open space on two or three sides. Attached units may have side-by-side and/or stacked configurations. Examples of courts include cottage housing and courtyard apartments.

2. Density. Each detached court development must include at least six units.

3. Maximum Building Width and Depth. Building width applies to a single wing of a building along the street frontage, not to the entire building with courtyard.

a. R-1: 60 feet width, 90 feet depth.

b. R-2: 60 feet width, 100 feet depth.

c. R-3: 60 feet width, 130 feet depth.

d. R-4: 60 feet width, 140 feet depth.

4. Building Orientation and Access.

a. Buildings and dwelling units abutting a street must have primary facades and entries oriented to the street. Other dwelling units must orient to the courtyard.

b. All dwelling units must have direct pedestrian access to the courtyard; the courtyard must have a pedestrian path that connects to the public sidewalk.

c. Buildings or units abutting both a street and a courtyard must provide building orientation per MTMC 19.32.020(A) on both the street and courtyard.

d. Articulation. Primary shared entrances, such as those to courtyard apartment buildings, must be emphasized with building articulation techniques per MTMC 19.32.020(D).

5. Outdoor Common Open Space. The courtyard shall consist of common open space (courtyard) per MTMC 19.30.120. It must be accessible to all units. Courtyards with a dimension of less than 15 feet shall not be included in the calculated open space.

6. Carriage Houses (Dwelling Units Above a Garage). In detached court developments, one carriage housing unit is allowed for each three detached units.

a. Exception. Unlimited carriage houses are allowed where parking spaces are accessed from an alley or rear driveway, or when earning any bonus per MTMC 19.30.045.

Figure 19.32.060.F1. Example of carriage house. Image Credits: Zillow.

Figure 19.32.060.F2. Examples of Courts. Image Credits: Redfin, Matt Miner, Madrona Company, Anhalt Apartments.

(Ord. 2885 § 2 (Exh. A), 2025).

This section defines design standards specific to elements eligible for development bonuses per MTMC 19.30.045 and Table 19.30.030.

A. Alleys. Alleys eligible for development bonuses must meet all the following criteria:

1. New alleys are not allowed if they require the removal of a noninvasive tree greater than 16 inches in diameter at breast height (DBH).

2. Placement. Must occur on the rear eight feet of a lot. Deviations to avoid removal of trees greater than 16 inches DBH will be permitted.

3. Width. 16 feet minimum for full alleys; eight feet minimum for half alleys.

4. Other Standards. Other dimensions, materials and markings must be consistent with the Engineering Development Manual.

B. Midblock Connections. Midblock connections must meet all the following criteria:

1. Length. Must connect from front sidewalk to rear lot line.

2. Minimum Width.

a. Pedestrian/bike path only: eight feet minimum. This portion of a midblock connection may count toward any required common open space.

b. Pedestrian/bike/automobile: 12 feet minimum for driveway and four feet minimum sidewalk for pedestrians. Pedestrian paths must be differentiated from vehicular/bike paths by either a change in material or a grade separation.

3. Landscaping. Areas not designated for travel shall include shrubs, trees, or other landscaping consistent with Chapter 19.130 MTMC, Landscape Development and Site Buffering. The landscaping portion of a midblock connection may count toward any required common open space.

4. Steps may be incorporated and must meet applicable accessibility guidelines.

5. Signage. Signs affirming public access must be posted and must be compliant with City’s prototype.

Figure 19.32.090.B1. Precedent images showing midblock connections. Image Credits: b9 Architects, Fletcher Studio, Zillow.

Figure 19.32.090.B2. Diagram illustrating applicable alley and midblock connections.

Figure 19.32.090.B3. Precedent showing fine-grained connections in an existing middle housing neighborhood.

C. Improved Parking Courts. Improved parking courts must meet all the following criteria below. Overall intent is to identify the space as pedestrian-oriented to foster those activities and to promote safety.

1. Entries. Entries to units, either primary or side/rear doors, at a ratio of one entry per garage door. Each entry must include address signage and 15 square feet minimum “personalization” area in front of the unit door that does not overlap with maneuvering space for automobiles.

2. Surface. A curbless driving/walking surface made of unit pavers, natural stone, brick, or saw-cut concrete with decorative pattern. Asphalt and concrete do not qualify. Slopes must be less than five percent.

3. Landscaping. Ten square feet minimum of landscaping per unit entry.

4. Transparency. Twenty-five percent facade transparency of all abutting facades, to promote surveillance of the court.

5. Lighting. Building-mounted or string lighting.

Figure 19.32.090.C Precedent images showing improved parking courts. Image Credits: Zillow.

(Ord. 2885 § 2 (Exh. A), 2025).