Chapter 18.32


18.32.010    Applicability of chapter.

18.32.020    Purpose of chapter.

18.32.030    Maximum number of lots.

18.32.040    Minimum cluster performance criteria.

18.32.050    Density bonus earned.

18.32.060    Administrative approval of one- to four-lot cluster short subdivisions.

18.32.010 Applicability of chapter.

This chapter is applicable and can be utilized at the subdivider’s option in residential single areas which have a “cluster,” “cluster detached,” or “cluster attached,” or “planned” use qualifier as part of the land use classification of the city’s comprehensive plan. [Ord. 10833 § 1, 1997; Ord. 9135 § 5(A), 1982].

18.32.020 Purpose of chapter.

The purpose of this chapter is to allow variation in the required minimum lot size, provided the same overall density is maintained, so as to preserve open space, tree cover, recreation areas or scenic vistas; or to reduce the amount of stormwater runoff, streets and utilities where appropriate. [Ord. 2017-03-009 § 13; Ord. 10833 § 1, 1997; Ord. 9135 § 5(B), 1982].

18.32.030 Maximum number of lots.

The maximum number of lots which can be created utilizing this procedure can be determined by dividing the total property size by the specified density found in the land use classification within the neighborhood plan. A density bonus may be earned in addition to the underlying density specified in the neighborhood plan in accordance with BMC 18.32.050. [Ord. 10833 § 1, 1997; Ord. 9135 § 5(C), 1982].

18.32.040 Minimum cluster performance criteria.

The cluster subdivision development option may be utilized if all of the following parameters that may apply are satisfied:

A. The proposed design addresses any special conditions, prerequisite considerations or significant environmental elements identified in the relevant neighborhood plan.

B. The proposed design is compatible with the existing topography and preserves natural resources such as mature trees or wooded areas, significant wetlands, streams and wildlife habitat.

C. Connecting links between existing parks and open spaces are provided along streams, ridgelines, ravines, shorelines, hillsides, and wooded areas whenever possible.

D. Fifteen percent of the total site area shall be set aside as open space.

E. Minimum Design Criteria.*

Minimum Lot Area:

4,000 sq. ft. total

Minimum Lot Width:

40 feet detached

30 feet attached

Minimum Lot Depth:

60 feet

Minimum Yards:




15 feet



Five feet detached



0 feet attached (only on common property line)



15 feet

*    Lot area, width and depth requirements are for 100 percent usable area. Larger lot area may be required if portions of the lot are unusable.

All lots shall contain the necessary area to provide required parking, buildable area with appropriate setbacks, and private usable space. Setbacks shall be determined prior to final approval of the plat.

F. Parking.

1. Tandem parking and required parking in the front yard setback (driveway) shall be allowed outright in cluster subdivisions.

2. Shared driveways are encouraged.

3. Parking areas shall utilize permeable surfacing if feasible. “Feasible” shall mean the design criteria, limitations, and infeasibility criteria for each LID BMP as described in the Ecology Manual.

4. Additional public parking areas, as determined by the technical review committee, may be required within subdivisions having lots smaller than 6,000 square feet.

G. Transition of Smaller Lot Sizes. When developing in an established neighborhood, lot sizes should best represent existing neighborhood patterns adjacent to existing development, and transition to smaller lot sizes within the plat. [Ord. 2017-03-009 § 14; Ord. 10833 § 1, 1997].

18.32.050 Density bonus earned.

A density bonus of up to 50 percent maximum may be earned, at the discretion of the hearing examiner, if the options listed below are provided in addition to the minimum cluster performance criteria listed in BMC 18.32.040(A) through (D). The minimum lot area requirement may be waived by the city council if any of the following are achieved.

Bonus up to the amount listed below may be granted by the hearing examiner based on the quality of the features offered, the extent to which the development exceeds the minimum level which qualifies for a bonus and extent to which the public will benefit from the offered option. The hearing examiner may impose conditions to ensure a public benefit of approved bonuses.

A. Up to a 50 percent bonus for the purchase and transfer of all or part of the development rights of a parcel identified as meeting any of the following criteria:

1. A parcel, tract or land area declared as a suitable density donor by city council resolution.

2. A parcel with a valid planned development contract which provides for a development right transfer.

3. A parcel previously zoned for residential uses that, due to the adoption of subsequent governmental regulations and as determined by city council, is unlikely to achieve even 50 percent of the original allowable density, resulting in the loss of the city’s potential infill capacity.

B. Up to a 50 percent bonus when a project is able to provide at least one-half of the total unit count of the project as affordable housing, as defined by the city council resolution, inclusive of a provision to maintain said housing as such for a reasonable duration determined by city council.

C. Up to a 50 percent bonus for the redevelopment of an area considered in need of revitalization as declared by city council resolution.

D. Up to a 25 percent bonus for the development of a neighborhood park and related improvements that satisfies the needs of the immediate neighborhood as determined by the parks and recreation department except when approval of the city council is required.

E. Up to a 15 percent bonus for providing at least 15 percent additional open space that is not otherwise restricted from development by environmental regulations.

F. Up to a 15 percent bonus for restoring a degraded natural area which would provide significant public enjoyment if enhanced.

G. Up to a 10 percent bonus for providing enhanced perimeter buffering of adjacent, less compatible uses that the hearing examiner determines would make a cluster subdivision a more compatible neighbor. [Ord. 2002-10-069 § 37; Ord. 10833 § 1, 1997].

18.32.060 Administrative approval of one- to four-lot cluster short subdivisions.

A. Cluster short subdivision proposals with four or fewer lots shall be considered and approved administratively. Said proposals shall be consistent with cluster subdivision criteria outlined in BMC 18.32.040 and follow the approval procedure of Chapter 18.12 BMC and as provided below.

B. A public hearing shall be scheduled if it is determined there are significant planning issues or significant neighborhood opposition in which case the proposal shall follow the procedures in Chapter 21.10 BMC for a Type III-A process. The director may make the decision to require a Type III-A process at any time prior to making a decision on the application.

C. Appeals of an administrative decision regarding a cluster short subdivision shall follow the procedures in Chapter 21.10 BMC.

D. Any bonus requested in a four or fewer lot cluster subdivision shall follow the procedures in Chapter 21.10 BMC. [Ord. 2005-08-066; Ord. 2002-10-069 § 37; Ord. 10833 § 1, 1997].