Chapter 17.94
Windsor Zoning Code · 2026-06 edition · ingested 2026-07-07 · Windsor
Two-Unit Dwelling and Lot Split Development Standards
17.94.010 Purpose. ¶
The purpose of this chapter is to establish standards for the development of two-unit residential dwelling developments and lot splits within singleunit residential zoning districts in accordance with California Government Code Sections 65852.21 and 66411.7 and to implement the goals and policies of the Town's Housing Element, including providing additional housing opportunities and a diversity of housing types. [Source: Draft language from Town staff]
17.94.020 Applicability. ¶
The requirements of this section shall apply to urban lot splits and the development and use of two-unit residential dwelling developments within a single-unit zoning district. In compliance with Article 2 (Zones, Allowable Uses, and Development Standards), single-unit zoning districts are Rural Residential (RR), Estate Residential (ER), Surrounding Residential (SR), and Village Residential (VR). SB9 lot splits and units are prohibited in all other zoning districts. [Source: Draft language from Town staff]
17.94.030 Conflict with other Requirements. ¶
In the event of a conflict between the requirements of this chapter and other provisions of this Code or other Town Codes, the provisions established in this chapter shall control. [Source: Draft language from Town staff]
17-233
(Supp. No. 53)
17.94.040
TOWN OF WINDSOR CODE
17.94.040 Interpretation. ¶
The provisions of this chapter shall be interpreted to be consistent with the provisions of California Government Code Sections 6585.2.21 and 66411.7 and shall be applied in a manner consistent with State law. The Town shall not apply any requirement or development standard provided for in this chapter to the extent prohibited by any provision of State law. [Source: Draft language from Town staff]
17.94.050 Definitions. ¶
A. Individual Property Owner. An individual property owner is the natural person holding fee title individually or jointly in the person's own name or a beneficiary of a trust that holds fee title. It does not include any corporation or corporate person of any kind (partnership, limited partnership, limited liability company, C corporation, S corporation, etc.), except for a community land trust (as defined by Revenue and Taxation Code Section 402.1(a)(11)(C)(ii) or a qualified nonprofit corporation (as defined by Revenue and Taxation Code Section 214.15). [Source: Draft language from Town staff]
B. New Primary Dwelling. A new primary dwelling is a new, additional dwelling unit that is created, but does not include an accessory dwelling unit or junior accessory dwelling unit. [Source: Draft language from Town staff]
C. Single-Unit Residential Zone(s). A single-unit residential zone includes the Rural Residential (RR), Estate Residential (ER), Surrounding Residential (SR), Village Residential (VR), and any property within a residential Planned Development (PD) district where a single-unit dwelling is an allowed use. [Source: Draft language from Town staff]
D. SB9 Two-Unit Residential Development. A SB9 two-unit residential development is a housing development containing no more than two
(2) primary residential units within a singleunit residential zone that qualifies for ministerial review pursuant to California Government Code Section 65852.21 and this section. A housing development contains two (2) residential units if it proposes no more than two (2) new units or to add one (1) new unit to one (1) existing primary unit. [Source: Draft language from Town staff]
- E. Urban Lot Split. An urban lot split shall have the same meaning as stated in California Government Code Section 66411.7. [Source: Draft language from Town staff]
17.94.060 Allowed Locations. ¶
An urban lot split or two-unit residential development shall only be allowed on parcels within single-unit residential zoning districts that allow single-unit dwellings as an allowed use as defined in this chapter and identified in Article 2 (Zones, Allowable Uses, and Development Standards). An urban lot split or two-unit residential development is prohibited on any parcel that is not zoned for single-unit residential uses. [Source: Draft language from Town staff]
17.94.070 Qualifying Requirements. ¶
A proposed urban lot split or two-unit residential development shall meet all of the following requirements in order to qualify for ministerial review, in compliance with the provisions of this chapter and California Government Code Sections 65852.21 and 66411.7. It shall be the responsibility of the applicant to demonstrate, to the reasonable satisfaction of the Director, that each of these requirements is satisfied. [Source: Draft language from Town staff]
A. The property is located in a single-unit residential zoning district. [Source: Draft language from Town staff]
B. The property does not include wetlands, hazardous waste site, prime farmland,
(Supp. No. 53)
17-234
ZONING CODE
17.94.080
FEMA-designated flood plains or regulatory floodways, or located in an earthquake fault or high fire severity zones, or subject to a conservation easement, based upon maps or regulations established by State or Federal regulatory agencies. [Source: Draft language from Town staff]
C. The property is not located within a historic district or on property included on the State Historic Resources Inventory, as defined in California Public Resources Code Section 5020.1, or within a site that is designated or listed as a landmark or historic property on the Town's Historic Register. [Source: Draft language from Town staff]
D. The proposed development does not require the demolition or alteration of deed restricted affordable housing. [Source: Draft language from Town staff]
E. The proposed development does not require the demolition or alteration of housing subject to rent control. [Source: Draft language from Town staff]
F. The proposed development does not require the demolition or alteration of housing that has been occupied by a tenant within the past three (3) years. [Source: Draft language from Town staff]
G. The proposed development does not require the demolition or alteration of housing that has been withdrawn from the rental market in the past fifteen (15) years. [Source: Draft language from Town staff]
H. The property is owned solely by one (1) or more individual property owners. [Source: Draft language from Town staff]
I. No unpermitted construction shall exist on the property. [Source: Draft language from Town staff]
J. The following additional requirements shall apply to urban lot split applications.
The parcel proposed to be subdivided shall not have been established through a prior urban lot split. [Source: Draft language from Town staff]
The parcel proposed to be subdivided ("subject lot") is not adjacent to any parcel that was established through an urban lot split by the owner of the subject lot or by any person acting in concert with the owner of the subject parcel. [Source: Draft language from Town staff]
17.94.080 General Requirements. ¶
A. Prohibited Uses. The following are prohibited.
Residential Use Only. Non-residential use is prohibited on any lot created through an urban lot split or containing a SB9 twounit residential development. [Source: Draft language from Town staff]
Short-Term Rental Prohibited. The rental of any dwelling unit on a lot created through an urban lot split or containing an SB9 two-unit residential development shall be for terms of not less than thirty (30) consecutive days. [Source: Draft language from Town staff]
Nonconforming Conditions. The design of an urban lot shall not create nonconforming conditions on the parcels created. The correction of legal nonconforming zoning conditions is not a condition for ministerial approval of a parcel map for an urban lot split. [Source: Draft language from Town staff]
B. Number of Dwelling Units Allowed. The number of dwelling units allowed on a qualifying parcel shall comply with the following:
- Urban Lot Split. No more than two (2) dwelling units may be constructed or main-
17-235
(Supp. No. 53)
17.94.090
TOWN OF WINDSOR CODE
tained on a lot that results from an urban lot split. For the purposes of this chapter, the two-unit limitation applies to primary dwelling units, accessory dwelling units, and junior accessory dwelling units. [Source: Draft language from Town staff]
- Two-Unit Residential Development. On lots not created through an urban lot split, two (2) primary dwelling units are permitted when in conformance with the requirements of this section. For the purposes of this chapter, the two-unit limitation applies to primary dwelling units, accessory dwelling units, and junior accessory dwelling units. [Source: Draft language from Town staff]
17.94.090 Permit Application and Review Procedures. ¶
A. Application. An application for a qualifying project as specified in Section 17.94.070 (Qualifying Requirements), urban lot split or twounit residential development shall be submitted on a form prepared by the Department, along with all information and materials prescribed by such form or required by the Director. No application shall be accepted unless it is completed as prescribed and is accompanied by payment of all applicable fees. [Source: Draft language from Town staff]
B. Application Requirements. The following information shall be included in the application for qualifying projects established in this chapter:
Two-Unit Residential Dwelling Application. An SB9 unit shall be reviewed and processed through a Building Permit application. The Building Permit application shall include the following:
a. Information required by Section 17.94.110;
b. A completed and signed SB9 TwoUnit Development Application form; and
c. Information and submittal requirements included in the SB9 Two-Unit Development Application form.
Urban Lot Splits. An SB9 urban lot split shall be reviewed through an SB9 lot split application:
a. Information required by Section 17.94.100;
b. Completed and signed SB9 Urban Lot Split Application form;
c. Information and submittal requirements included in the SB9 Urban Lot Split Application form; and
d. Information required by the Town's Subdivision Ordinance for tentative parcel maps.
C. Fees. Development of qualifying projects established in this chapter shall be subject to all applicable fees, including development impact fees, and assessments, duly adopted by the Town in the Master Fee Schedule. [Source: Draft language from Town staff]
D. Review. Consistent with State law, the Director shall consider and approve or disapprove a complete application for an SB9 two-unit residential development or an urban lot split ministerially, without discretionary review or public hearing. [Source: Draft language from Town staff]
E. Action. The Director shall decide whether to approve or deny an SB9 urban lot split or SB9 two-unit development application. No public notice shall be given or public hearing held. [Source: Draft language from Town staff]
F. Approval. Approvals for qualifying projects shall comply with the following:
- Two-Unit Residential Dwelling. In approving an application for an SB9 Two-Unit
17-236
(Supp. No. 53)
ZONING CODE
17.94.100
Development, the Director shall find that the application complies with the requirements of this chapter and the intent of Government Code Sections 65852.21 and 66411.7. [Source: Draft language from Town staff]
- Urban Lot Splits. In approving an application, that Director shall find that an SB9 Urban Lot Split application complies with the requirements of this chapter, the intent of Government Code Sections 65852.21 and 66411.7, and the Town's Subdivision Ordinance. [Source: Draft language from Town staff]
G. Denial—Specific, Adverse Effects. Notwithstanding anything else in this chapter, the Director may deny an application for an SB9 two-unit residential development or a parcel map for an urban lot split if the Building Official makes a written finding based on a preponderance of evidence, that the project would have a specific adverse impact, as defined and determined in California Government Code Section 65589.5, on either public health and safety or on the physical environment and for which there is no feasible method to satisfactorily mitigate or avoid the specific adverse impact. [Source: Draft language from Town staff]
H. Notification of Action. The Director shall issue a written notice of the decision, which shall be provided to the applicant and property owner, if different than the applicant. [Source: Draft language from Town staff]
I. Effective Date of Approval. The ministerial approval of an SB9 two-unit residential development or a parcel map for an urban lot split does not take effect until the Town has confirmed that all required documents have been recorded and a copy of the recorded documents have been provided to the Director and Town Engineer. [Source: Draft language from Town staff]
J. Hold Harmless. Approval of an SB9 two-unit residential development or parcel map for an urban lot split shall be conditioned on the property owner agreeing to defend, indemnify and hold harmless the Town, its officers, agents, employees, and/or consultants from all clams and damages (including attorney's fees) related to the approval and its subject matter. Source: Draft language from Town staff]
17.94.100 Urban Lot Splits—Development and Design Standards. ¶
A. General. An urban lot split shall conform to all objective requirements in this section, the Subdivision Map Act, and the Town's Subdivision Ordinance, except as otherwise provided in this section. [Source: Draft language from Town staff]
B. Dedications and Improvements. No dedications of right-of-way or off-site improvements shall be required solely for an urban lot split. [Source: Draft language from Town staff]
C. Parcel Size. The tentative parcel map for an urban lot split must subdivide an existing lot and shall comply with the following requirements: [Source: Draft language from Town staff]
No more than two (2) lots shall be created.
Each lot shall be forty (40) percent of the lot area of the lot proposed to be subdivided.
Each newly created lot shall be a minimum of one thousand two hundred (1,200) square feet.
D. Easements. Easements shall comply with the following: [Source: Draft language from Town staff]
- The owner shall enter into an easement agreement with each utility/public service provider to establish easements that are
17-237
(Supp. No. 53)
17.94.100
TOWN OF WINDSOR CODE
sufficient for the provision of public services and facilities to each of the resulting lots.
quired by the Town's Subdivision Ordinance does not apply to Urban Lot Splits. [Source: Draft language from Town staff]
- G. Parcel Width. The minimum parcel width shall be forty (40) feet. [Source: Draft language from Town staff]
Each easement shall be shown on the tentative parcel map and the final parcel map.
Copies of the unrecorded easement agreements shall be submitted with the application. The easements shall be recorded against the property prior to final map approval.
H. Setbacks. Setback areas for Urban Lot Splits shall comply with the following standards:
- Easement Accessible Parcels: Parcels accessed by an easement shall comply with the following standards:
E. Parcel Frontage. The following types of parcel frontages are allowed: [Source: Draft language from Town staff]
- a. There shall be no front property line. [Source: Draft language from Town staff]
A minimum of forty (40) feet of lot frontage on a public street is required for both parcels.
- b. The rear property line is the line that is generally parallel to the public rightof-way from which the lot gains access, and that abuts the properties that are not a part of the Urban Lot Split. [Source: Draft language from Town staff]
Where forty (40) feet of lot frontage is not proposed, the following shall apply:
a. Access Via Easement. Access shall be provided by an easement for ingress and egress and emergency vehicle access that is a minimum of twenty (20) feet in width for the entire length of the corridor. The access corridor shall be kept free and clear of structures, and shall not be used for the parking of vehicles; or [Source: Draft language from Town staff]
- c. The remaining properties shall be considered side property lines. [Source: Draft language from Town staff]
Access Corridor Accessible Parcels: Parcels accessed by an access corridor shall comply with the following standards:
- a. The front setback is the property line that abuts the public street and is the entire length of the access corridor. [Source: Draft language from Town staff]
b. Access Via Corridor (flag parcel). Access shall be provided by an access corridor that is a minimum of tewnty (20) feet in width for the entire length of the corridor. The access corridor shall be kept free and clear of buildings, structures, and shall not be used for the parking of vehicles. [Source: Draft language from Town staff]
- b. The rear property line is the line that is generally parallel to the public rightof-way from which the lot gains access, and that abuts the properties that are not a part of the Urban Lot Split. [Source: Draft language from Town staff]F. Parcel Depth. The minimum parcel depth shall be forty-five (45) feet. The parcel depth re-
- 17-238
(Supp. No. 53)
ZONING CODE
17.94.110
c. The remaining properties shall be considered side property lines. [Source: Draft language from Town staff]
I. Modifications by the Director. The Director may modify the objective standards when necessary for an SB9 Urban Lot Split to meet the minimum required lot size of one thousand two hundred (1,200) square feet. The applicant shall request the modification in writing as part of the SB9 application and provide information in support of the requested modification. [Source: Draft language from Town staff]
17.94.110 Two-Unit Dwelling—Development and Design Standards. ¶
A. General. An SB9 two-unit residential development on an existing parcel or developed on a parcel created by an urban lot split shall be subject to the standards included in this chapter, including the requirements of this section. [Source: Draft language from Town staff]
B. Unit Size. The maximum size of each new primary unit is limited to one thousand two hundred (1,200) square feet. When an existing single-unit dwelling is converted to a duplex, each of the resulting units shall not exceed one thousand two hundred (1,200) square feet. [Source: Draft language from Town staff]
C. Height. The maximum height is limited to one (1) story and eighteen (18) feet when located within the rear setback required by the underlying zoning district or two (2) stories and thirty-five (35) feet when located outside of the setback required by the underlying zoning district. [Source: Draft language from Town staff]
D. Setbacks. The following minimum setbacks shall be maintained from property lines for each new primary unit, any garages, and accessory structures that are attached to the new primary dwelling. Detached garages and ac-
- cessory structures shall comply with the requirements of Section 17.40.230 (Residential Accessory Structures and Uses). The setback for construction on a parcel that abuts a public street that has not been fully improved shall be measured from the ultimate street right-ofway. [Source: Draft language from Town staff]
Front. Twenty (20) feet.
Interior side. Four (4) feet.
Street side. Ten (10) feet.
Rear. Four (4) feet.
E. Structure Separation. Structures shall be separated by a minimum of six (6) feet between the primary dwelling unit and all detached accessory structures on the site, including all residential units, garages, and accessory structures. [Source: Draft language from Town staff]
F. Allowed Encroachments. Encroachments into required setbacks shall be allowed consistent with Section 17.20.040 (Setback Measurement and Exceptions). [Source: Draft language from Town staff]
G. Reduction of Setbacks. A required minimum setback may be reduced when application of the required setback would physically preclude the development or maintenance of two (2) dwellings units on a parcel or physically preclude any new dwelling unit from being eight hundred (800) square feet in floor area. [Source: Draft language from Town staff]
H. Existing Structures. No increased setback is required for an existing legally established structure or new primary dwelling unit constructed to the same dimensions and in generally the same location as an existing legally established structure, provided that the new primary dwelling unit shall not be larger than eight hundred (800) square feet. [Source: Draft language from Town staff]
17-239
(Supp. No. 53)
17.94.110
TOWN OF WINDSOR CODE
I. Parcel Coverage. Maximum parcel coverage shall not exceed the parcel coverage allowed by the zoning district in which the parcel is located, unless the lot coverage standard would preclude establishment of an eight hundred (800) square foot dwelling unit. If the parcel coverage requirement would preclude establishment of an eight hundred (800) square foot dwelling unit, the maximum parcel coverage may be increased to the extent needed to allow an eight hundred (800) square foot dwelling unit. [Source: Draft language from Town staff]
J. Open Space. Each new primary dwelling unit shall provide a minimum of two hundred (200) square feet of continuous private open space, with minimum interior dimensions of ten (10) feet. The private open space shall be open and unobstructed from the ground to the sky, except as allowed in Section 17.20.040 (Setback Measurement and Exceptions). The private open space area may be located in the required rear, side, or street side setback. [Source: Draft language from Town staff]
K. Required Off-Street Parking. Off-street parking spaces shall comply with the following:
Number of Spaces Required. One (1) offstreet parking space shall be required for each new primary dwelling unit, unless the location of the lot complies with one (1) of the following. Information demonstrating that the lot meets one (1) of the following requirements shall be submitted with the Building Permit application, when requesting relief from the parking requirement: [Source: Draft language from Town staff]
a. The parcel is located within one-half (½) mile walking distance of a highquality transit corridor as defined in Section 21155 of the California Public Resources Code or a major transit stop as defined in Section 21064.3 of the
- California Public Resources Code. [Source: Draft language from Town staff]
b. The lot is located within one (1) block of a car-share vehicle location. [Source: Draft language from Town staff]
Covered and Uncovered Parking Allowed. The required off-street parking space may be covered or uncovered. [Source: Draft language from Town staff]
Compliance with Established Parking Standards. The size, location and design of off-street parking spaces shall comply with Chapter 17.30 (Parking, Loading, and Access) of this Code. [Source: Draft language from Town staff]
Maintenance. The area designated for covered parking shall remain open. Storage cabinets, mechanical equipment, washers and dryers, and similar items shall not encroach into the required parking area. Required covered parking spaces shall maintain the ability to park the required number of vehicles at all times. [Source: Draft language from Town staff]
L. Refuse Storage Area. All developments shall provide each unit with the appropriate number of containers for recyclable, organics, and non-recyclable solid waste ("refuse containers") as required by the Town's waste hauler and shall comply with all of the following requirements: [Source: Draft language from Town staff]
Refuse containers shall be stored in designated storage areas only and not within the required covered parking area. [Source: Draft language from Town staff]
- The area required by each container shall comply with the required refuse receptacles used by the Town's refuse hauler at the time of development. [Source: Draft language from Town staff]
17-240
(Supp. No. 53)
ZONING CODE
17.94.110
- Refuse areas shall be paved and located in an area with access to and from the street. [Source: Draft language from Town staff]
M. Deed Restriction. Prior to approval of a parcel map for an urban lot split and/or the issuance of a Building Permit for the development of an SB9 two-unit development, the owner(s) of record of the property shall provide to the Director a copy of a covenant agreement, declaration of restrictions, or similar deed restriction ("deed restriction") recorded against the property, and that includes all the following: [Source: Draft language from Town staff]
Expressly requires the rental of any dwelling unit on the property be for a term longer than thirty (30) consecutive days.
Expressly prohibits any nonresidential use of the lot.
Expressly prohibits primary dwelling units located on the same lot from being owned or separately conveyed from one another.
Expressly requires all fee interest in each lot and all dwellings to be held equally and undivided by all individual owners of the lot.
Expressly prohibits condominium air space division and common interest developments on the property.
Expressly prohibits more than two (2) dwelling units from being constructed or maintained on a lot that results from an urban lot split.
States that the property was formed and/or developed pursuant to the provisions of this section and is therefore subject to the Town regulations set forth in this section, including all applicable limits on dwelling size and development.
States that:
a. The deed restriction is for the benefit of and is enforceable by the Town;
b. The deed shall run with the land and shall bind future owners, their heirs, and successors, and assigns;
c. Lack of compliance with the deed restriction shall be good cause for legal action against the owner(s) of the property;
d. If the Town is required to bring legal action to enforce the deed restriction, then the Town shall be entitled to its attorney's fees and court costs; and
e. The deed restriction may not be modified or terminated without the prior written consent of the Director.
N. Exceptions. The Director may approve an exception to objective zoning, subdivision, or design standards that would preclude two (2) eight hundred (800) square foot units from being built on a parcel.
Priority of Development Standards. The Town prioritizes the following development standards in the following descending order of priority, with the first development standard having the highest priority.
a. Height.
b. Front setback.
c. Open space.
d. Side or rear setback.
e. Lot coverage.
f. Building separation.
- New garages or accessory structures may only be allowed when they provide the required parking and provided that these structures due not preclude the construction of two (2) eight hundred (800) square foot dwelling units.
17-241
(Supp. No. 53)
17.96.010
TOWN OF WINDSOR CODE
Building standards, standards required by Federal, State, or local law for sanitation or safety reasons, the off-street parking requirements, and the lot size, access, and frontage requirements will not be waived or modified unless required by State law.
As part of the application, the applicant shall provide a written explanation that: specifically describes each development standard the applicant seeks to modify or waive, and to what extent; demonstrates why the waiver or modification of each development standard is needed to prevent physically precluding the construction of up to two (2) primary dwelling units on the lot and/or each new unit from being at least eight hundred (800) square feet in floor area; and demonstrates that the requested waivers and/or modifications are consistent with the priority set forth in this subsection.
- O. Expiration of Approval. The approval of an SB9 two-unit residential development shall become null and void if construction has not commenced within one (1) year of the approval and diligently advanced until completion of the project. In the event construction of the project is commenced, but not diligently advanced until completion, the rights granted pursuant to the approval shall expire if the Building Permits for the project expire.