A. 
The city finds that lot size averaging is an appropriate regulatory approach to help protect critical areas and allow for greater flexibility in design so irregular parcels can be used more efficiently.
B. 
Lot size averaging is an approach to dividing land that allows a parcel to be divided such that some of the resulting lots are smaller than the minimum lot size required in the applicable zone, as long as the average of all of the lot sizes, including open space and stormwater detention/retention areas, remains equal to or above the minimum lot size.
C. 
The total number of lots in a development implementing lot size averaging cannot exceed the maximum number of lots allowed on the subject property per the applicable zone if averaging was not being used.
D. 
Lot size averaging does not assure that the number of lots available to a developer on a particular parcel will be the same as the number available if the property were not encumbered by critical area exclusions.
E. 
Lot size averaging is primarily concerned with allowing smaller lot sizes to account for critical areas and other site constraints, whereas Cluster Subdivision, as described in 19.46, addresses site constraints by providing more flexibility in dimensional standards and lot configuration. Both systems still maintain a standard gross density across the entire parcel but use different mechanisms to achieve this goal. Either system may be used.
(Ord. 1144-12 § 2 (Exh. A); Ord. 1284-17 § 2 (Exh. B); Ord. 1353-21 § 2 (Att. A); Ord. 1420-25, 7/24/2025)
A. 
Lot size averaging provisions of this chapter apply to, and may be used by, developers of land who are dividing land in conformance with the provisions of this title, and who meet the provisions set out in subsection B of this section.
B. 
Lot size averaging provisions of this chapter apply to and may be used by developers of land in the following zones:
1. 
Low/moderate density, LDR (SMC § 16.12.010).
2. 
Moderate density, MDR (SMC § 16.12.020).
3. 
High density, HDR (SMC § 16.12.030).
(Ord. 1144-12 § 2 (Exh. A); Ord. 1284-17 § 2 (Exh. B); Ord. 1353-21 § 2 (Att. A); Ord. 1420-25, 7/24/2025)
A. 
Lot size averaging only applies to creation of lots for single-family and middle housing, including detached, duplexes, triplexes and townhomes.
B. 
Lot size averaging shall not be used to create lots for multifamily dwellings as defined by SMC § 16.04.040.
C. 
No lot shall be reduced to less than 80% of the minimum lot size required in the applicable zone, and each lot shall be at least 3,000 square feet in area.
D. 
No lot shall be reduced in width to less than 40 feet (regardless of lot depth).
E. 
This section shall not be implemented in conjunction with any provisions of the Sultan Municipal Code that allow density credits or cluster development.
F. 
Developments utilizing lot size averaging shall not receive preliminary or final approval as phased developments unless each phase meets the lot size averaging standards for the total land area included in that phase.
(Ord. 1144-12 § 2 (Exh. A); Ord. 1284-17 § 2 (Exh. B); Ord. 1353-21 § 2 (Att. A); Ord. 1420-25, 7/24/2025)
A. 
The following calculation shall be used to determine the maximum number of lots available to a given development:
1. 
Add together all areas where proposed:
a. 
Area in lots;
b. 
Areas designated as open space or recreational uses;
c. 
Surface detention/retention facilities meeting the standards of subsection A.5 of this section.
2. 
Divide the total area of subsection A.1 of this section by the total number of proposed lots.
3. 
If the average lot size as computed under subsection A.2 of this section equals or exceeds the minimum lot area requirement of the zone in which the property is located, the minimum lot area requirement will be satisfied for the purposes of lot size averaging.
4. 
Critical areas and their buffers permanently protected under Chapter 17.10 SMC may not count toward calculations for lot size averaging.
5. 
Surface detention/retention facilities may count toward calculations for lot size averaging only if the detention/retention facility:
a. 
Is designed to not require security fencing under the EDDS standards; and
b. 
The facility is either:
i. 
Designed to appear as a natural wetland system; or
ii. 
Provides active or passive recreational benefits in a natural landscaped setting.
(Ord. 1144-12 § 2 (Exh. A); Ord. 1284-17 § 2 (Exh. B); Ord. 1353-21 § 2 (Att. A); Ord. 1420-25, 7/24/2025)
A. 
Road standards required for development of land divisions by this title are required in developments without regard to their implementation of lot size averaging standards of this chapter.
B. 
All standard utility improvements required for land divisions by this title are required in developments without regard to their implementation of lot size averaging standards of this chapter.
C. 
All standards for lot layout, setbacks, access, easements, and any other development standard for individual lots required for land divisions by this title are required in developments without regard to their implementation of lot size averaging standards, unless otherwise explicitly addressed within this chapter.
(Ord. 1144-12 § 2 (Exh. A); Ord. 1284-17 § 2 (Exh. B); Ord. 1353-21 § 2 (Att. A); Ord. 1420-25, 7/24/2025)