HomeMy WebLinkAboutRMC 4-2-110F_DEVELOPMENT STANDARDS FOR MIDDLE HOUSING_COMPLETESection 4-2-110F of the Renton Municipal Code is repealed and replaced as follows:
4-2-110F1 DEVELOPMENT STANDARDS FOR MIDDLE HOUSING
1. Purpose: The provisions of this subsection are available as an alternative to the development of
typical detached single-family dwelling units with the intention of generating diversified housing
types in conformance with RCW 36.70A, by providing land use, development, design, and other
standards for middle housing developments.
2. Applicability: The provisions of this subsection shall apply to all middle housing development
within the following zones: Resource Conservation (RC), Residential-1 (R-1), Residential-4 (R-4),
Residential-6 (R-6), and Residential-8 (R-8) zones.
3. Exemptions: The provisions of this subsection do not apply to:
a. Portions of a lot with critical areas designated under RCW 36.70A.170, or their buffers as
required by RCW 36.70A.170, except for critical aquifer recharge areas where a single-family
dwelling unit is an allowed use provided that any requirements to maintain aquifer recharge
are met.
b. A watershed serving a reservoir for potable water if that watershed is or was listed, as of July
23, 2023, as impaired or threatened under section 303(d) of the federal clean water act (33
U.S.C. Sec. 1313(d)).
c. Lots within designated urban separators by countywide planning policies as of July 23,
2023.
d. Lots less than 1,000 square feet in size.
e. Lots created through the splitting of a single residential lot.
4. Authority and Responsibility:
a. Nothing in this subsection requires the issuance of a building permit for middle housing if
other federal, state, and local requirements for a building permit are not met.
b. Nothing in this subsection affects or modifies the responsibilities of the city to plan for or
provide “urban governmental services” as defined in RCW 36.70A.030.
c. The city shall not approve a building permit for middle housing without compliance with the
adequate water supply requirements of RCW 19.27.097.
d. The same development permit and environmental review processes shall apply to middle
housing that apply to single-family dwelling units, unless otherwise required by state law
including, but not limited to, shoreline regulations under chapter 90.58 RCW, building codes
under chapter 19.27 RCW, energy codes under chapter 19.27A RCW, or electrical codes
under chapter 19.28 RCW.
5. Additional Requirements: When determining a lot’s development potential for middle housing,
additional factors for consideration include:
a. Infrastructure and Services: Any lot proposed for middle housing development must ensure
adequate access to utility services, emergency services, and all other required improvements,
sufficient to serve the development.
b. Lot Access: Access requirements and street design and development standards shall be
provided in accordance with RMC 4-6-060. Lots that are accessed via a shared driveway are
limited to the maximum number of dwelling units that may take access from a shared
driveway, pursuant to RMC 4-6-060J, Shared Driveway Standards.
6. Maximum Dwelling Units per legal Lot: A maximum number of dwelling units are allowed per
legal lot, within applicable zones, as shown in the following table. For the purposes of this
subsection, accessory dwelling units and single-family dwelling units are included in the
calculation of maximum dwelling units per lot. For middle housing unit lot subdivisions, the
maximum dwelling units per legal lot shall apply to the parent site as a whole, rather than to
individual unit lots.
Lots in all Applicable Zones
Lots located within ¼ mile
walking distance20 of a Major
Transit Stop
Lots with Affordable Housing
4 dwelling units per lot. 6 dwelling units per lot.
6 dwelling units per lot,
provided at least 2 units are
reserved for affordable
housing pursuant to
subsection 9, Affordable
Middle Housing Units.
7. Middle Housing Typologies: The following middle housing typologies are allowed within
applicable zones under this subsection:
a. Duplexes
b. Triplexes
c. Fourplexes
d. Stacked Flats
e. Townhouses
f. Courtyard apartments
8. Maximum Dwelling Units Per Building: A maximum of four (4) attached dwelling units is
allowed per building. For the purposes of this subsection, accessory dwelling units are included in
the calculation of maximum dwelling units per building.
9. Affordable Middle Housing Dwelling Units: To qualify for additional units under the affordable
housing provisions of subsection 6, an applicant shall rent or sell the required number of units as
affordable housing, in compliance with the following standards:
a. Affordable Housing Eligibility Criteria: Dwelling units that qualify as affordable housing shall
have costs, including utilities other than telephone, that do not exceed 30 percent of the
monthly income of a household whose income does not exceed the following percentages of
median household income adjusted for household size, for King County, as reported by the
United States Department of Housing and Urban Development:
i. Rental housing: 60 percent.
ii. Owner-occupied housing: 80 percent.
b. Affordability Duration and Recalculation: Affordable housing units provided under this
subsection shall remain affordable housing for a term of fifty (50) years from the date the
affordable housing agreement is recorded. For the full term a dedicated affordable housing
unit is required to remain affordable, the most recent affordability rates on file with the City
Clerk’s Office shall be applied at any point a new owner or renter is allowed to purchase or
rent the unit, and at the time of each rental rate adjustment. For owner-occupied units,
compliance with the most recent affordability rates on file with the City Clerk’s office shall be
verified at the time of purchase. Affordability shall not be recalculated for owner-occupied
units so long as the unit remains occupied by the same owner who qualified at time of their
purchase.
c. Affordable Housing Agreement: Prior to issuing any building permit or final plat approval,
the applicant shall record a covenant or deed restriction that ensures the continuing rental or
ownership of units subject to these affordability requirements, consistent with the conditions
in chapter 84.14 RCW, for a period of no less than 50 years. The covenant or deed restriction
shall address criteria and policies to maintain public benefit if the property is converted to a
use other than that which continues to provide for permanently affordable housing.
d. Affordable Housing Unit Conditions: The units dedicated as affordable housing shall
comply with the following conditions:
i. Affordable units shall be provided in a range of sizes comparable to other units in the
development.
ii. The number of bedrooms in affordable units shall be in the same proportion as the
number of bedrooms in units within the entire development.
iii. Affordable units shall be distributed throughout the development and have
substantially the same functionality as the other units in the development.
10. Development Standards: Middle housing developments shall comply with the standards
applicable to single family development, pursuant to RMC 4-2-110A, Development Standards for
Residential Low Density and Medium Density Zones – Primary Structures.
11. Design Standards: Middle housing developments shall comply with the design standards
applicable to single family development, pursuant to RMC 4-2-115, Residential Design and Open
Space Standards. In addition, Middle housing developments shall comply with the following
standards, where applicable:
a. Entries: All ground-related dwelling units fronting a street and/or common open space shall
provide a covered porch with a minimum depth of five feet (5'). Dwelling units that are
accessed entirely from an internal common corridor are exempt from this requirement
provided the shared entry features a covered porch with a minimum depth of five feet (5').
b. Pedestrian access: A paved pedestrian connection at least three feet wide is required
between each middle housing building and the sidewalk (or the street if there is no sidewalk).
Driveways may be used to meet this requirement.
c. Courtyard Apartments – Open Space: Courtyard Apartments shall provide open space in
conformance with the following:
i. At least one outdoor common open space is required.
ii. Common open space shall be bordered by dwelling units on two (2) or three (3) sides.
iii. Common open space shall be a minimum dimension of 15 feet on any side.
Iv. Parking areas and vehicular areas do not qualify as a common open space.
12. Parking and Driveway Standards: Middle housing developments shall comply with all
driveway and parking design standards applicable to single family development, pursuant to RMC
4-4-080, Parking, Loading and Driveway Regulations, except for the number of required parking
spaces, which shall be subject to the following:
a. Off-Street Parking Spaces Required for Middle Housing:
Lots 6,000 sq. ft. or Less Lots greater than 6,000 sq.
ft.
Lots located within ½ mile
walking distance20 of a Major
Transit Stop
A minimum of 1.0 per dwelling
unit.
A minimum of 2.0 per dwelling
unit.
No off-street parking required.
Developers that provide off-
street parking spaces, when
not required by this
subsection, are eligible for
parking incentives pursuant to
subsection 12.b of this
section.
b. Parking Incentives for Middle Housing Development Located within ½ Mile Walking
Distance20 of a Major Transit Stop: Middle housing developments that provide off-street
parking spaces as shown in the following table, when not otherwise required by this
subsection, are eligible for the following parking incentives, provided the increase is feasible
and consistent with the Surface Water Design Manual. For each increase in number of parking
spaces provided, the applicant is eligible for an additional parking incentive. For example,
applicants that provide a minimum of 2.0 parking spaces per dwelling unit are eligible for the
incentives below.
Number of Off-Street Parking
Stalls Provided Incentives
A minimum of 1.0 per dwelling unit.
10% Increase in Maximum
Impervious Surface Area permitted
by the subject zone, pursuant to
RMC 4-2-110A; and
A minimum of 2.0 per dwelling unit.
5% Increase in Maximum Building
Coverage permitted by the subject
zone, pursuant to RMC 4-2-110A.
13. Conflicts: In the event of a conflict between this subsection and other development
regulations applicable to middle housing, the standards of this subsection prevail.
1 Please see Section 4-2-110I, Conditions Associated with Residential Development Standards Tables, for
explanation of table footnotes.