Menlo Park City Zoning Code
CHAPTER 16
79 ACCESSORY DWELLING UNITS 1
§ 16.79.010 Purpose.
(a)
Increase the supply of smaller units and rental housing units by allowing accessory dwelling units to locate on lots which contain existing or proposed single-family dwellings and existing two (2) family and multifamily dwellings;
(b)
Establish standards for accessory dwelling units to ensure that they are compatible with existing neighborhoods; and
(Ord. 688 § 1 (part), 1983; Ord. 923 § 1 (part), 2003; Ord. 1000 § 2 (part), 2013; Ord. 1005 § 2 (part), 2014; Ord. 1031 § 3 (part), 2017; Ord. 1066 § 2 (part), 2020)
§ 16.79.020 Definitions.
In addition to the terms defined in Chapter 16.04 (Definitions), the following terms shall have the following meanings:
(1) "Accessory dwelling unit"(A) (B) (C) (D) (E) (F)
(ADU) means an attached or a detached residential dwelling unit that provides complete independent living facilities for one (1) or more persons and is located on a lot with a proposed or existing primary residence. The unit shall contain permanent provisions for:
Living;
Sleeping;
Eating;
Cooking;
Sanitation;
Exterior access separate from the primary dwelling.
The following units are also considered ADUs: | |
(A) | An efficiency unit as defined in the building code; and |
(B) | A manufactured home, as defined in Section 18007 of the Health and Safety Code. |
(2) "Attached accessory dwelling unit"
means an accessory dwelling unit that is constructed as a physical expansion (i.e., addition) of an existing primary dwelling unit, including construction of a new basement underneath a primary dwelling unit to accommodate an ADU. In some cases attached accessory dwelling unit is used interchangeably with "interior accessory dwelling unit."
 Figure 1: Attached accessory dwelling unit |
(3) "Detached accessory dwelling unit"
means a dwelling unit that is (A) constructed as a separate structure from the primary dwelling unit; (B) contained within the existing space of an accessory structure; or (C) constructed as an addition to an existing or proposed accessory building.
 Figure 2: Detached accessory dwelling unit |
(4) "Interior accessory dwelling unit"
means a dwelling unit that is (A) contained within the existing space of a primary dwelling unit, including within its living area, basement, or attached garage; (B) constructed as part of a proposed primary dwelling unit; or (C) created from nonlivable space of a multifamily dwelling. In some cases, an interior accessory dwelling unit is used interchangeably with "attached accessory dwelling unit."
 Figure 3: Interior accessory dwelling unit |
(5) "Junior accessory dwelling unit"
(JADU) means a dwelling unit that is no more than five hundred (500) square feet in size and contained entirely within an existing or proposed single-family dwelling. A JADU shall include cooking facility with appliances and a food preparation counter and storage cabinets that are of reasonable size in relation to the size of the JADU. A JADU may include separate sanitation facilities or may share sanitation facilities with the primary dwelling. A JADU must have exterior access separate from the primary dwelling.
(6) "Public transit"
means a location, including, but not limited to, a bus stop or train station, where the public may access buses, trains, subways, and other forms of transportation that charge set fares, run on fixed routes, and are available to the public.
(Ord. 1066 § 2 (part), 2020)
§ 16.79.030 Permitted uses.
(a)
Attached or Interior ADUs. Attached or interior ADUs which do not exceed one thousand (1,000) square feet or fifty percent (50%) of an existing primary dwelling, whichever is greater, and have no more than two (2) bedrooms are a permitted use in all zoning districts which allow single-family, multifamily or mixed use which permits residential use.
(b)
Detached ADUs. Detached ADUs which do not exceed one thousand (1,000) square feet and have no more than two (2) bedrooms are a permitted use in all zoning districts which allow single-family, multifamily or mixed use which permits residential use.
(c)
JADUs. JADUs are a permitted use in all single-family districts.
(Ord. 688 § 1 (part), 1983; Ord. 923 § 1 (part), 2003; Ord. 1000 § 2 (part), 2013; Ord. 1005 § 2 (part), 2014; Ord. 1031 § 3 (part), 2017; Ord. 1066 § 2 (part), 2020; Formerly 16.79.020)
§ 16.79.040 Conditional uses.
Accessory dwelling units that require modification to the development regulations set forth in this chapter, except for Sections 16.79.050(a), Number of Units, and 16.79.100(c), Subdivision, are conditionally permitted in the single-family residential zoning districts, subject to the use permit requirements of Chapter 16.82.
(Ord. 688 § 1 (part), 1983; Ord. 923 § 1 (part), 2003; Ord. 1000 § 2 (part), 2013; Ord. 1005 § 2 (part), 2014; Ord. 1031 § 3 (part), 2017; Ord. 1066 § 2 (part), 2020; Formerly 16.79.030)
§ 16.79.050 Regulations applicable to single-family districts.
(a)
Number of Units. A maximum of three (3) units, including the primary dwelling, shall be allowed on a single-family lot. An applicant may have only one (1) JADU or attached/interior ADU on a single-family lot, but not both.
(b)
Interior/Attached ADUs. One (1) interior ADU or one (1) attached ADU per single-family lot is permitted, subject to the following requirements:
(1)
Access. The ADU must have exterior access independent of the main unit.
(2)
Setbacks.
(A)
For interior ADUs created within the living space of an existing single-family home, the side and rear setbacks must be sufficient for fire and safety.
(B)
For new attached ADUs, the side and rear setbacks shall be four (4) feet.
(C)
Interior and attached ADUs shall comply with the front yard setback applicable to the primary dwelling.
(3)
Size. The total floor area of an attached or interior ADU may not exceed fifty percent (50%) of an existing primary home or one thousand (1,000) square feet, whichever is greater.
(4)
Overall Floor Area Limit/Lot Coverage. An ADU may exceed the total floor area and/or building coverage applicable to the parcel by up to eight hundred (800) square feet provided the ADU is built concurrently with, or after, the existing or proposed primary unit and other structures on site.
(5)
Height. An ADU may not exceed the maximum height allowed for the primary dwelling and must comply with the daylight plane requirement.
(c)
Detached ADUs. One (1) detached ADU per single-family lot is permitted, subject to the following requirements:
(1)
Detached ADUs Eight Hundred (800) Square Feet or Less in Size.
(A)
Setbacks. Detached ADUs eight hundred (800) square feet or less in size shall not encroach into a four (4) foot side and rear yard setback. The ADU shall comply with the front yard setback applicable to the primary dwelling.
(B)
Overall Floor Area/Parcel Coverage. An ADU eight hundred (800) square feet or less in size may exceed the total floor area and/or building coverage applicable to the parcel by up to eight hundred (800) square feet provided the ADU is built concurrently with, or after, the existing or proposed primary unit and other structures on site.
(C)
Height. An ADU may not exceed sixteen (16) feet in height and is exempt from the daylight plan requirement applicable to the primary dwelling.
(D)
Conversions. If any of the regulations conflict with the regulations in Section 16.79.060(b), an ADU created by conversion of an existing building shall be subject to Section 16.79.060(b).
(2)
Detached ADUs Greater Than Eight Hundred (800) Square Feet in Size.
(A)
Setbacks. A detached ADU greater than eight hundred (800) square feet in size shall meet the side setback applicable to the primary dwelling and not encroach into a ten (10) foot rear yard setback. The ADU shall comply with the front yard setback applicable to the primary dwelling.
(B)
Size. An ADU may not exceed a total floor area of one thousand (1,000) square feet.
(C)
Overall Floor Area/Parcel Coverage. An ADU over eight hundred (800) square feet in size may not exceed the total floor area and/or building coverage applicable to the parcel.
(D)
Height. An ADU may not exceed seventeen (17) feet in height and must comply with the daylight plane that shall begin at a horizontal line nine (9) feet, six (6) inches above the average natural grade at a line three (3) feet from the side property lines and shall slope inwards at a forty-five (45) degree angle. There are no permitted intrusions into the daylight plane. "Average natural grade" means the average of the highest and lowest points of the natural grade of the portion of the lot directly below a line three (3) feet from the side property lines.
(E)
Conversions. If any of the regulations conflict with the regulations in Section 16.79.060(b), an ADU created by conversion of an existing building shall be subject to Section 16.79.060(b).
(Ord. 1066 § 2 (part), 2020)
§ 16.79.060 Additional development standards.
(a)
Lot Size. No minimum lot size shall be required for a newly created ADU.
(b)
Conversions. No setbacks shall be required for ADU conversions of (1) existing living space in the primary dwelling, (2) accessory buildings constructed in the same location and to the same dimensions, (3) attached or detached garages in single-family neighborhoods.
(c)
Other Standards. Except as specified in this chapter, ADUs shall comply with lot coverage, floor area limit, open space and other zoning standards applicable to the primary dwelling, except in no event shall the application of any of these standards preclude at least an eight hundred (800) square foot ADU that is up to sixteen (16) feet in height.
(Ord. 1066 § 2 (part), 2020)
§ 16.79.070 Regulations applicable to JADUs.
(a)
A permitted junior accessory dwelling unit must be constructed within the walls of the existing or proposed primary dwelling unit.
(b)
A JADU may not exceed five hundred (500) square feet.
(c)
No minimum lot size shall be required for a JADU.
(d)
The bathroom may be shared with the primary dwelling or may be separate (if separate it counts towards five hundred (500) square feet).
(e)
A JADU must have a separate entrance from the primary dwelling.
(f)
No parking is required for the JADU.
(g)
Owner Occupancy Required. The property owner must reside in either the remaining portion of the primary dwelling unit or the newly created JADU. Owner occupancy shall not be required if the owner is another governmental agency, land trust, or housing organization.
(h)
The owner must record a deed restriction, which shall run with the land, and shall include both of the following:
(1)
A prohibition on the sale of the junior accessory dwelling unit separate from the sale of the single-family residence, including a statement that the deed restriction may be enforced against future purchasers.
(2)
A restriction on the size and attributes of the junior accessory dwelling unit that conforms with this chapter.
(Ord. 1066 § 2 (part), 2020)
§ 16.79.080 Parking.
(a)
An ADU must provide one (1) off-street parking space. The parking space may be covered or uncovered, in any configuration and may be located in the front, side or rear setback.
(b)
If off-street parking is removed to allow for an ADU in a single-family district, the on-site parking need not be replaced.
(c)
If the garage is converted to an ADU, no replacement parking for the primary dwelling in a single-family district is required.
(d)
No parking for the ADU is required if the ADU is:
(1)
Located within one-half (1/2) mile walking distance of public transit;
(2)
Located within an architecturally and historically significant historic district;
(3)
An interior ADU;
(4)
Not eligible for on-street parking permits, but on-street permits are available; or
(5)
Within one (1) block of a car share vehicle.
(Ord. 1066 § 2 (part), 2020)
§ 16.79.090 Regulations applicable to multifamily districts.
(a)
Interior ADUs. ADUs are allowed within portions of existing multifamily dwelling structures that are not used as livable space including storage rooms, boiler rooms, passageways, attics, basements, and garages, subject to the following requirements:
(1)
Number of ADUs. At least one (1) ADU within an existing multifamily building shall be permitted and no more than twenty-five percent (25%) of the existing multifamily dwelling units may take advantage of developing ADUs under this provision.
(2)
Building Standards. Each newly created ADU unit must comply with California building standards and related requirements.
(3)
Livable Space Conversions Prohibited. Existing livable space may not be converted into a full or partial ADU.
(4)
JADUs Prohibited. JADUs are not permitted.
(b)
Detached ADUs. Up to two (2) detached ADUs are permitted on a multifamily lot that has an existing multifamily building subject to the following requirements:
(1)
Setbacks. The maximum rear and side yard setback is four (4) feet. The front setback shall be the same as applicable to the multifamily building;
(2)
Height. The maximum height is sixteen (16) feet;
(3)
Up to two (2) detached ADUs are permitted on a multifamily lot in addition to the interior ADUs described above.
(Ord. 1066 § 2 (part), 2020)
§ 16.79.100 Other requirements.
(a)
Tenancy. For ADUs built after January 1, 2020, no owner occupancy requirements shall apply to either the primary dwelling or the ADU. For ADUs built before January 1, 2020, either the main dwelling or the accessory dwelling unit shall be occupied by the property owner when both units are occupied as dwelling units. If a property owner does not occupy one (1) of the dwelling units, the property owner may apply for a nontenancy status for a term of one (1) year through a registration process established by the community development director or designee. To be eligible for the registration process, a property owner must have lived at the subject property for a minimum of two (2) years of the previous five (5) years from the date of application. The property owner may renew the registration annually, not to exceed four (4) years in total, subject to the review and approval of the community development director or designee, pursuant to the following criteria and process established by the community development director or designee:
(1)
The application for the registration and renewal(s) shall be accompanied by a fee, set by the city council.
(2)
The application for registration and renewal shall state the reason for the request and provide supporting documentation. The registration shall be approved for any of the following reasons: (A) temporary job relocation, with the intent to return, (B) relocation for school (e.g., mid-year career change), and (C) physically unable to live in the house.
(3)
The application shall provide a property management plan that includes the name and contact information to address issues or concerns about the use of the property should they arise. The plan should also include information about parking, including (A) a site plan with the parking layout for the property, (B) how parking will be assigned between tenants, and (C) an action plan that demonstrates how parking issues will be resolved effectively and efficiently between tenants if tandem parking is provided.
(4)
A use permit is required for nontenancy status longer than four (4) years or for waiver of the requirement that the owner reside in the unit for not less than two (2) of the previous five (5) years prior to the date of application or for a reason other than those stated in subsection (a)(2) of this section.
(b)
Short-Term Rentals. For ADUs built after January 1, 2020, the rental of an ADU must be for a term longer than thirty (30) days. Short-term ADU rental for less than thirty (30) days is prohibited.
(c)
Subdivision. An ADU may be rented separately from the primary dwelling but may not be sold or otherwise conveyed separately from the primary residence. (This requirement shall not apply to a unit complying with AB 587 (i.e., "Habitat for Humanity" exception).)
(Ord. 1066 § 2 (part), 2020)
§ 16.79.110 Delay in enforcement of unpermitted ADUs.
For any unpermitted ADU built before January 1, 2020, upon an owner's request, the city's building official shall delay enforcing any building standards if the building official determines that correcting the violation is not necessary to protect health and safety. This provision shall sunset on January 1, 2025.
(Ord. 1066 § 2 (part), 2020)
§ 16.79.120 Application review and approval process.
Each development of an ADU or JADU requires review for compliance with this chapter as part of the building permit review process for the creation of an ADU or JADU.
(a)
Application. Concurrent with the submittal of a complete building permit application for the ADU or JADU, the ADU/JADU checklist, which demonstrates compliance with all of the ADU/JADU development regulations, shall be submitted. The application shall include plans showing the details of the proposed unit per submittal guidelines established by the community development director or designee.
(b)
Compliance Determination. The community development director or designee shall make a determination of compliance prior to issuance of the building permit for the ADU/JADU. The determination of the community development director or designee is final and not subject to appeal.
(c)
All applications for ADU/JADUs that meet and comply with the requirements under this chapter shall be approved without discretionary review or a hearing within sixty (60) days after receipt of a substantially complete application. The application shall be denied if the proposed ADU/JADU does not comply with all applicable requirements of this chapter or it may be conditionally approved subject to conditions that will bring the proposed accessory dwelling unit into compliance with this chapter.
(Ord. 1031 § 3 (part), 2017; Ord. 1066 § 2 (part), 2020; Formerly 16.79.060)
§ 16.79.130 Compliance with state law.
To the extent any provision of this chapter is inconsistent with state law governing ADUs or JADUs, the applicable state law shall govern.
(Ord. 1066 § 2 (part), 2020)
§ 16.79.140 Two (2) unit housing developments and urban lot splits (SB 9).
(a)
Pursuant to the authority provided by Section 65852.21(f) of the Government Code, no accessory dwelling unit or junior accessory dwelling unit shall be permitted on any lot in a single-family zoning district if: (1) an urban lot split has been approved pursuant to Chapter 15.31; and (2) a two (2) unit housing development has been approved for construction pursuant to Chapter 16.77.
(Ord. 1096 § 4, 2023)