Division 3. General Development Standards
Chapter 21.31
LOT DEVELOPMENT STANDARDS
Sections:
21.31.020 Interpreting tables in this chapter.
21.31.030 Residential zoned lot and residential density standards.
21.31.040 Nonresidential zoned lot and residential density standards.
21.31.050 Additional provisions applicable to lot and residential density standards.
21.31.010 Purpose.
This chapter establishes development standards applicable to the creation of lots and residential densities. (Ord. 737 § 2 (Att. A), 2022)
21.31.020 Interpreting tables in this chapter.
When interpreting the tables found in this chapter, the zone districts are located on the vertical columns and the corresponding development standards to each zone are located on the horizontal rows of the tables. (Ord. 737 § 2 (Att. A), 2022)
21.31.030 Residential zoned lot and residential density standards.
The pertinent development standards for residential densities, minimum lot area, minimum lot width and minimum street lot width applicable to each residentially zoned lot are set forth in Table 21.31.030.
Standards 
Low Density 
Moderate Density 
Medium Density 
High Density 


R1 
R4 
R6 
R8 
R12 
R18 
R24 
R48 

Minimum Lot Area* (Square Feet) 
35,000 
9,000 
6,000 
5,000 
2,500 
2,500 
2,500 
2,500 
Minimum Density 
None 
3 du/ac 
4 du/ac 
6 du/ac 
9 du/ac 
14 du/ac 
17 du/ac 
31 du/ac 
Maximum Density 
1 du/ac 
4 du/ac 
6 du/ac 
8 du/ac 
12 du/ac 
48 du/ac 
24 du/ac 
48 du/ac 
Minimum Street Lot Width* 
100 ft1,2 
60 ft 
50 ft 
30 ft 
30 ft 
30 ft 
30 ft 
30 ft 
Minimum Lot Width* 
100 ft1 
60 ft 
50 ft 
30 ft 
25 ft 
25 ft 
25 ft 
25 ft 
Notes: 1. Within the R1 zone, lots having a “lot area” less than 15,000 square feet may have a minimum street lot width of 60 feet. 2. Within the R1 zone, lots adjoining a culdesac may have a minimum street lot width adjoining a culdesac of 75 feet. *See definitions for “lot area,” “lot width, street” and “lot width” in WMC 21.11A.130. 
(Ord. 737 § 2 (Att. A), 2022)
21.31.040 Nonresidential zoned lot and residential density standards.
The pertinent requirements for residential densities, minimum lot area, minimum lot width, and minimum street lot width applicable to each nonresidentially zoned lot is determined by the zone in which the lot is located and the corresponding development standards in Table 21.31.040.
Standards 
Commercial Zones 
Industrial Zones 
Other Zones 


NB 
TB 
CBD 
GB 
O 
T/I 
I 
P/I 
P 

Minimum Lot Area (Square Feet) 
2,500 
1,500 
1,500 
2,500 
None 

Maximum Residential Density 
Not applicable 
24 du/ac 
See Note 1 
Not applicable 

Minimum Street Lot Width* 
None 

Minimum Lot Width* 
25 ft 
25 ft 
25 ft 
25 ft 
25 ft 
25 ft 
25 ft 
25 ft 
25 ft 
Notes: 1. Densities are based on residential floor area ratio standards. See WMC 21.32.050. *See definitions for “lot area,” “lot width, street” and “lot width” in WMC 21.11A.130. 
(Ord. 737 § 2 (Att. A), 2022)
21.31.050 Additional provisions applicable to lot and residential density standards.
The following provisions are applied in combination with WMC 21.31.030 and 21.31.040.
(1) Calculating Residential Density. The following apply to calculating residential density on a site:
(a) Minimum and maximum residential densities on a site shall be computed by multiplying the existing lot area for the site prior to any dedication for public street rightsofway by the corresponding density standards for the zone set forth in Tables 21.31.030 and 21.31.040; and
(b) If the computed density results in a fraction, the fraction shall be rounded to the nearest whole number as follows:
(i) Fractions of 0.50 and above shall be rounded up; and
(ii) Fractions of less than 0.50 shall be rounded down;
(c) When a site is divided by two or more zones, density standards shall apply separately to each zoned area of the site using the corresponding density standards applicable to each zoned area, except all computations of density resulting in a fraction shall be rounded down to the nearest whole number;
(d) The total number of dwelling units and/or lots in a development shall not exceed the maximum density of the zone.
(2) Minimum Residential Density. The minimum residential density standards set forth in Table 21.31.030 (Tourist Business zone does not have a minimum residential density standard) may be adjusted as follows:
(a) If wetlands, fish and wildlife habitat conservation areas, or geological sensitive areas, including associated buffers, are present and placed in a native growth protection area, minimum density may be adjusted by the minimum density multiplier in Table 21.31.050 based on the percentage of the site encumbered by the native growth protection area.
(b) The Director may waive the minimum residential density standards set forth in Table 21.31.030 if the applicant demonstrates one or more of the following conditions are satisfied:
(i) The layout of lots, access, and buildings is such that at least one lot remains dividable in the future into buildable lots that can satisfy the minimum residential density standards as applied to the entire development;
(ii) In the R12 through R48 zones, the land area of the site to accommodate community stormwater facilities exceeds 10 percent of the lot area; or
(iii) The site contains a historical landmark designation pursuant to Chapter 21.47 WMC.
Percentage of Site in Native Growth Protection Area 
Minimum Density Multiplier 

Up to 20 percent 
90 percent 
More than 20 percent and less than 40 percent 
80 percent 
More than 40 percent and less than 60 percent 
60 percent 
More than 60 percent and less than 80 percent 
40 percent 
More than 80 percent 
20 percent 
How to apply the minimum density multiplier: 1. Multiply the minimum residential density standard in Table 21.31.030 by the applicable minimum density multiplier (do not round up or down) to yield an adjusted minimum residential density standard; 2. Calculate the number of lots/dwelling units per subsection (1)(a) of this section using the adjusted minimum residential density standard; 3. Round any fractions down to the nearest whole number. 
(3) Minimum Street Lot Width. The minimum street lot width shall not apply to flag lots satisfying the requirements in WMC 21.92.030(1)(e).
(4) Lot Size Averaging. Lot size averaging may be applied to subdivisions and short subdivisions located within the R1, R4, R6, and R8 zones in lieu of the lot area requirements in Table 21.31.030, provided the following conditions are satisfied:
(a) A minimum of three lots (does not include “tracts” as defined in WMC 21.11A.210) must be included to qualify for lot size averaging;
(b) The lot area may be modified as follows:
(i) The average lot area of all lots of the subdivision or short subdivision, excluding tracts reserved exclusively for special uses such as open space, roads, or native growth protection areas, shall not be less than the minimum lot area of the zone;
(ii) No lot area shall be more than 1.15 times the minimum lot area of the zone, and no lot shall be less than 0.85 times the minimum lot area of the zone;
(c) The total number of lots in the subdivision or short subdivision shall not exceed the maximum density of the zone;
(d) Except for lot area, all other requirements for the zone including minimum lot width shall apply; and
(e) Lot size averaging shall not be applied in combination with other Woodinville Municipal Code provisions allowing modifications to lot area requirements. (Ord. 737 § 2 (Att. A), 2022)