The following uses and facilities are permitted as principal uses in all districts, and the provisions of this title shall not prevent the construction, installation, maintenance or operation thereof:

A.

Public or private streets serving property in the district in which they are situated and the use of such streets for normal and usual street purposes.

B.

When used for public utility purposes, water or gas pipes, mains or conduits, electric distribution lines, communication lines, sewers or sewer mains and minor incidental appurtenances to any of the above. All electric transmission and/or distribution lines and all communication lines and all appurtenances thereto shall conform to the following:

1.

All new transmission, distribution and service lines for electricity and communication shall be installed underground.

2.

Existing overhead lines and appurtenances thereto may be replaced unless provided for otherwise in subsection B (5) and (6) below, as long as the lines are not enhanced. That is, the lines shall not have additional capacity to serve either the immediate vicinity or more distant areas.

3.

All new equipment appurtenant to transmission, distribution and service lines for electricity and communication shall be installed underground; however, pad-mounted transformers may be permitted if the planning commission finds there is no adverse visual effect from the public right-of-way, from a neighboring property or from within the property itself.

4.

When any program for improvement of streets is instituted by the town or by any other person having jurisdiction over any street improvements and such improvements require replacement, relocation, construction, reconstruction or alteration of lines, appurtenances thereto or parts thereof, such changes to the electric and communication lines and facilities shall conform to the provisions of this title for new lines and appurtenant equipment.

5.

Existing overhead electric service lines which provide service to an individual property may remain until such time as any of the following occur, at which time the lines shall be placed underground: the location of the service box is moved; the route of the overhead wires from the pole to the structure is changed, or the point where the wires attach to the structure is changed; or whenever a service is increased above a total of one hundred ampheres.

6.

Existing overhead communication service lines shall be placed underground whenever this title requires that existing overhead electric service lines be placed underground.

7.

The undergrounding provisions for cable television transmission, distribution and service lines shall be established in the franchise ordinance adopted by the town.

8.

Undergrounding of existing lines and related facilities on an applicant's property and within adjacent street rights-of-way, utility easements or other public property may be required in connection with zoning amendments, conditional use permits and variances.

9.

The provisions of subsection B 1, 3, 4, 5, 6 and 8 hereof shall not apply in those cases wherein the planning commission determines that underground installation is not feasible or practicable and that there is no reasonable alternative location or design for the installation of underground electric or communication lines or appurtenances thereto. The planning commission may establish policies for the administration of this paragraph. Any person aggrieved by the decision of the planning commission may appeal from the decision to the town council.

(Ord. 1990-256 § 2 (Exh. B) (part), 1990; Ord. 1967-80 § 1 (6300), 1967)

When a conditional use permit is granted therefor as provided in Chapter 18.72, the following uses and facilities are permitted in all districts as conditional uses:

A.

Major operating facilities of public utilities and other major utility installations when operating requirements necessitate a specific location in order to serve best the immediate vicinity or the town as a whole;

B.

Signs as permitted and regulated by Chapter 18.40;

C.

The designation and development of buildings and sites determined to be of historical significance by the planning commission so as to render such buildings and sites available for public enjoyment;

D.

Wireless communications facilities that serve primarily the town and its sphere of influence and that conform to the provisions of Chapter 18.41 of this title.

(Ord. 2011-393, § 5, 2011; Ord. 1997-295 § 2, 1997; Ord. 1987-219 § 1, 1987; Ord. 1986-210 § 1, 1986; Ord. 1982-190 § 1, 1982; Ord. 1969-99 § 3 (part), 1969; Ord. 1967-80 § 1 (6301), 1967)

The following uses or facilities are permitted in all districts as temporary uses:

A.

A voting place used in connection with a municipal or other public election;

B.

Structures and uses incidental to a construction operation, including temporary dwelling units that comply with subsection E. below, on the same or an adjoining parcel provided that such structures and uses are of a temporary nature and do not exist for a period longer than twelve months. Such time periods may be extended for structures and uses other than temporary dwelling units, by action of the Town Council;

C.

A festival, exhibit or other similar activity when of a noncommercial nature and sponsored by a group residing in the neighborhood, provided the total duration thereof does not exceed fourteen days;

D.

Signs as permitted and regulated by Chapter 18.40.

E.

Motor homes and travel trailers designed for human habitation are permitted as temporary dwelling units on residentially zoned parcels, provided each one complies with the following provisions:

1.

Has less than three hundred twenty square feet of internal living area and measures less than eight feet in width and forty feet in length.

2.

Is occupied by the owners of the principal dwelling who are unable to occupy the principal dwelling while it is being remodeled, because it is not suitable for occupancy.

3.

Is connected to a sanitary sewer or an on-site septic system.

4.

Is connected to an established power supply. A generator power supply is allowed only in an emergency situation (e.g., power outage during a storm).

5.

May be placed in a required setback if the ASCC finds the unit would not impact neighboring properties more than would be the case if it were located in conformance with setbacks and that the location in the setback allows for a more appropriate overall construction staging plan.

6.

Shall conform to a time limit set by the ASCC, but in no case more than one year. The ASCC approval shall indicate the anticipated starting date and the termination date. The actual starting date shall commence immediately when the temporary dwelling unit is brought on the site.

7.

The applicant shall submit a description of the need for the temporary dwelling unit and how the unit would relate to any use of the principal dwelling during the project. This shall include an explanation of how the temporary dwelling unit could impact the timely completion of the construction project.

8.

The applicant shall submit a construction staging plan that shows all aspects of the construction operation including any other temporary facilities such as a construction trailer or office. The plan shall demonstrate that there is adequate space and screening to accommodate the temporary dwelling unit and other normal construction uses and activities without undue burden on the neighborhood.

9.

The applicant shall show compliance with the requirements of this section on plans submitted with the building permit for the remodeling project along with supporting information as required by this section. The ASCC shall approve all temporary dwelling units concurrently with approval of the proposed remodel of the principal dwelling. All requirements shall be met prior to issuance of the building permit.

10.

The applicant shall post security approved by the town attorney in the amount of ten thousand dollars to guarantee removal of the temporary dwelling unit by the earlier of the termination date or ten days after the building official has approved occupancy of the principal dwelling ("removal date"). Additionally, if the temporary dwelling unit is not removed by the removal date, the applicant shall pay the town a fine of two hundred fifty dollars for each day beyond the removal date.

11.

The ASCC shall administer the provisions of this section. Neighbors shall be notified in accordance with Section 18.64.085.

(Ord. 2003-353, §§ 1, 2, 2003; Ord. 1967-80 § 1 (6302), 1967)

A. An accessory use is a related minor use which is either (a) necessary to the operation or enjoyment of a lawful principal use or conditional use, or (b) appropriate, incidental and subordinate to any such use. No use in any district shall be permitted as an accessory use which is not qualified as hereinabove set forth, or which constitutes in effect a conversion of a principal use to one not permitted in that district. This section shall apply to new construction and replacement fixtures. In addition to other uses meeting the qualifications set forth in this section, and subject to the limitations set forth in this title, the following accessory uses are permitted in all districts when located on the same parcel as the principal use:

1.

The installation and operation of necessary facilities and equipment in connection with such schools and other institutions as are permitted in the respective district;

2.

Recreation, refreshment and service buildings in public parks;

3.

Required off-street parking spaces and required off-street loading spaces as regulated by this title;

4.

Fences and walls subject to the height and area regulations of this title;

5.

Hedges, trees, shrubs and other ornamental planting;

6.

Horticulture;

7.

Electric and communication service lines provided that all such lines are placed underground except where exempted in accordance with the procedure set forth in subsection B of Section 18.36.010;

8.

Outdoor Illumination.

i.

Purpose. The purpose of this subsection is to provide clear regulations regarding allowable outdoor lighting. The town's general plan states: "Night lighting visible from the exterior of buildings should be strictly limited to that necessary for security, safety and identification. All night lighting, including signs, should be low intensity and shielded from view from residential areas." This chapter aims to provide regulations for outdoor lighting that will:

a.

Permit the use of outdoor lighting that does not exceed the minimum necessary for night-time safety, utility, security, and enjoyment.

b.

Minimize adverse offsite impacts of lighting such as light trespass and obtrusive light.

c.

Curtail light pollution, reduce skyglow and improve the nighttime environment for astronomy and star gazing in keeping with the dark sky movement.

d.

Help protect the natural environment from the adverse effects of night lighting.

e.

Conserve energy and resources to the greatest extent possible.

ii.

Definitions.

a.

Brightness shall be measured in lumens.

b.

Dark sky compliant fixture or equivalent shall mean a light fixture from which all light emitted directly or indirectly, is projected below a horizontal plane.

c.

Flood lighting shall mean any fixture which lights a large area, as opposed to an individual feature such as a step, path or doorway.

d.

Manual switch shall mean any light requiring a physical action to control, whether by hardwires at the property, phone or computer application, or other technology.

e.

Motion-sensor shall mean any light control which is trigged by motion.

f.

Photo-cell shall mean a light-sensitive control that switches lights on or off depending on the level of outdoor light.

g.

Timer shall mean any device which controls the hours or amount of time that a light fixture is illuminated.

iii.

Applicability. All outdoor lighting installed after the date of effect of this ordinance shall comply with these requirements. This includes, but is not limited to, new lighting, replacement lighting, or any other lighting whether attached to structures, poles, the earth, or any other location. These regulations are meant to apply only to the visible light spectrum.

a.

Exceptions.

1.

Lighting for signs shall be regulated by Chapter 18.40, Signs.

2.

Holiday lighting, including in trees, for up to sixty total days per calendar year.

iv.

Lighting Placement.

a.

Exterior doors shall have one fixture each.

b.

Garage doors may have one or two fixtures, which shall be limited to a total lumen count of one thousand one hundred twenty-five lumens.

c.

Low path, step and wall lights for safety and navigation purposes for pedestrian and other non-vehicular uses.

d.

Lighting for exterior patios and dining areas shall be recessed and shielded from off-site visibility.

v.

Fixture Type. All outdoor lighting fixtures shall be dark sky compliant or equivalent specifically, they shall include the following elements:

a.

Shield directing light downward;

b.

Bulb not protruding below horizontal plane at bottom of shield;

c.

Light spill limited to the object to be illuminated;

d.

Fixtures shall not have ability to swivel or adjust direction, except path lighting, which shall not swivel above a forty-five-degree angel from a vertical line down.

vi.

Lightinq Control. Lighting controls and technologies shall be implemented to the effect that outdoor lights are on only when needed and never during daylight. Controls shall function with dark sky compliant fixtures. Current technologies include manual switches, photo-cells, timers, and motionsensors. Any combination of these technologies may be used, with the following limitations:

a.

Motion-sensor lights shall be triggered only by motion within a property and shall not be activated by motion in adjacent property or rights-of-way.

b.

Photo-cells shall be used only to ensure lighting is off during the day, as opposed to on a night.

c.

Timers shall be included on all motion-sensor lights to ensure that illumination is limited. Timers shall be used only to turn lights off, not on.

d.

Lights shall self-extinguish within two minutes of being illuminated.

vii.

Prohibited Lighting. The following lighting types and systems are prohibited from being installed or used:

a.

Up-lighting;

b.

Lighting for night use of uncovered game courts, including tennis, paddle tennis, basketball, riding rings, and similar outdoor recreation facilities and areas;

c.

Aerial lasers and other focused beams;

d.

Flood lights or lighting;

e.

Searchlights;

f.

Lighting with no on/off switch or ability to be controlled;

g.

Any permanent or temporary lighting in which any single light source exceeds one thousand one hundred twenty-five lumens.

h.

Festoon, cafe, or any other string of exposed blubs.

viii.

Lighting Requiring ASCC Approval. The following light fixtures, placements, or types are generally discouraged and require ASCC approval in order to be installed:

a.

Lighting for landscaping, trees or structures, including entryway features, pillars and posts;

b.

Commercial parking lighting.

9.

Septic tanks and drain fields;

10.

Antennas designed to receive television or microwave signals transmitted from satellite or terrestrial stations. Antennas with diameters exceeding four feet are subject to review by the architectural and site control commission as provided for by paragraph 6 of subsection A of Section 18.64.010.

11.

Tennis courts and paddle tennis courts, provided the sum of the maximum depth of cut and maximum height of fill for such facilities shall not exceed the following:

B.

Accessory Dwelling Units and Junior Accessory Dwelling Units.

1.

Purpose. The purpose of this section is to define accessory dwelling units (ADUs) and Junior Accessory Dwelling Units (JADUs), and describe their development standards, review required, and additional regulations. ADUs and JADUs are allowed in certain situations in order to help achieve the town's goals which include but are not limited to:

a.

Encourage the development of ADUs and JADUs through a ministerial approval process;

b.

Create new housing units while respecting the existing character of the town;

c.

Provide housing that responds to residents' changing needs, household sizes, and increasing housing costs, and provide accessible housing for seniors and persons with disabilities;

d.

Offer environmentally friendly housing choices with less average space per person and smaller associated carbon footprints; and

e.

Promote provision of affordable housing for people who work in town.

2.

Definitions. The following definitions shall govern this section.

a.

Accessory Dwelling Unit, or ADU. An attached or detached residential dwelling unit that provides complete independent living facilities for one or more persons and is located on a lot with a proposed or existing primary residence. It shall include permanent provisions for living, sleeping, eating, cooking, and sanitation on the same parcel as the main building to which it is accessory. An accessory dwelling unit also includes:

i.

An efficiency unit, as defined in Section 17958.1 of the Health and Safety Code.

ii.

A manufactured home, as defined in Section 18007 of the Health and Safety Code.

iii.

Internal ADU. Created by converting existing or proposed interior space of a single-family or multi-family structure, such as bedrooms, attached garages, basements or attics, or a combination thereof. Converted space can also be within an existing accessory structure.

iv.

External ADU. A unit which requires new construction, either attached to or detached from the main building.

1.

Attached ADU. A unit which is attached to or part of the main building. Attached ADUs include new construction which is attached to the existing building, and a mix of new construction and converted space.

2.

Detached ADUs. A separate building, independent from the main building, built using new construction.

b.

Adjusted Maximum Floor Area, or AMFA. The maximum allowed floor area for a residential parcel, calculated by the town using the parcel's size, slope, mapped ground movement potential, and mapped flooding potential.

c.

Director. Planning and building director, also referred to as the town planner.

d.

Discretionary Review. Review of a project against the General Plan, municipal code, and Design Guidelines. The reviewing body exercises judgment in applying policies to a specific project in context and determining whether the required findings for approval can be made. The reviewing body considers public comment and may impose conditions of approval on the project.

i.

Staff Discretionary Review. A review process wherein the planning and building director shall review certain accessory dwelling unit applications in coordination with one member of the architecture and site control commission (ASCC).

ii.

Architectural and Site Control Commission, or ASCC. A review process wherein the full ASCC reviews projects at a public meeting.

e.

Efficiency Kitchen. A space containing a sink with a maximum waste line diameter of one and one-half inches, a 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.

f.

Existing Interior Space. For the purposes of internal ADU creation, existing interior space shall be within a building which was permitted by the town and passed its final building inspection.

g.

Guest House. A building separate from the main residence which includes a bedroom and may include a bathroom, but does not include a kitchen.

h.

Junior Accessory Dwelling Unit or JADU. A unit that is no more than five hundred square feet in size and contained entirely within a single-family residence. A JADU shall include an efficiency kitchen and may include separate sanitation facilities. A JADU shall have a separate external entrance from the main building. Junior accessory dwelling units do not constitute ADUs under this code.

i.

Main Building. This term is defined in Chapter 18.04 (definitions). For the purposes of this section, it describes the building to which an ADU is accessory. Main buildings can have a residential or non-residential use, as permitted by this title. This section interchangeably uses the term "primary residence" and "primary dwelling" to refer to residential main buildings.

j.

Ministerial Review. A review process which is objective in nature and involves no personal judgment. The reviewing body confirms that all requirements are satisfied before approving a project, and may not consider public comment or impose conditions of approval.

k.

Multifamily Structure. For the purpose of this section only, a structure with two or more attached dwelling units on a single lot is considered a multifamily structure. A supportive housing project consisting of two or more units is considered a multifamily structure provided the majority of the units have their own kitchen facility. The following are not multifamily structures for the purposes of this section:

1.

Multiple detached single-unit dwellings on the same lot;

2.

A single family dwelling containing a JADU or an interior ADU;

3.

A single family dwelling with (i) a JADU or an interior ADU and (ii) an exterior ADU, either attached or detached.

4.

A single family dwelling with more than one ADU.

l.

Second Address. An address issued by the planning and building department for a permitted accessory dwelling unit on a parcel that has an existing unit with a different address.

m.

Second Unit. See accessory dwelling unit.

3.

Applicability. ADUs and JADUs shall be permitted on all parcels in all zoning districts, where a main building is in existence or is proposed concurrently.

a.

Fire safety exception.

i.

Prohibition. ADUs are prohibited on parcels smaller than one acre whose direct vehicular access is from a road or cul-de-sac which (1) has a single point of ingress/egress and (2) has a width of less than eighteen feet.

ii.

Ingress/egress restriction. ADUs on parcels which are one acre or larger and whose direct vehicular access is from a road or cul-de-sac, which (1) has a single point of ingress/egress and (2) has a width of less than eighteen feet, shall comply with the setback requirements of the underlying zoning district, regardless of ADU size.

iii.

Additional restrictions. Any proposed external ADU, which does not comply with the underlying zoning or local setbacks governing the parcel, shall comply with and submit with the ADU application a completed Town of Portola Valley Fire Safety Checklist adopted by resolution of the town council. The checklist shall contain requirements for ADU construction methods and materials, defensible space and vegetation management. Such checklist requirements shall be additive to other applicable building and safety requirements.

b.

Geologic safety exception.

i.

Prohibition. ADUs are prohibited where construction is not permitted under Resolution No. 2746-2017 (or successive resolution or ordinance) ("Geologic Regulations") which governs construction on or near earthquake faults and traces and areas subject to active downslope movement as shown on the town's Geologic and Ground Movement Potential maps as updated from time to time.

ii.

Additional restrictions. ADUs located in areas Y* and N* shall comply with the town's Geologic Regulations.

4.

Development Standards. All existing development restrictions in the base zoning district shall apply, except as modified by this section. These requirements include but are not limited to coverage, open space, bulk, density, floor area and adjusted maximum floor area, impervious surface, height, setbacks, parking, site development, and outdoor lighting requirements.

a.

Number.

i.

One ADU and one JADU shall be permitted on all parcels smaller than three and one-half acres in size.

ii.

Two ADUs shall be permitted on parcels three and one-half acres or larger in size as follows: one ADU must be detached from the main building and one ADU must be internal. A JADU shall be permitted in lieu of an internal ADU.

b.

State Exemption ADU. As mandated by state law, any parcel zoned residential or mixed-use permitting residential shall be permitted to build one of the following applicable ADUs. The following ADUs shall be subject to ministerial review and are not subject to the town's lot coverage, AMFA, setback, height, or size standards. However, the safety exceptions in subsection 3.a. and 3.b. above shall apply.

i.

New construction. One detached ADU of up to eight hundred square feet, sixteen feet in height, and with four feet side and rear yard setbacks is allowed on residential lots containing one existing or proposed single-family dwelling.

ii.

Conversions/Interior units. One ADU or one JADU is permitted per lot within the existing or proposed space of a single-family dwelling or an existing accessory structure that contains exterior access and setbacks sufficient for fire and safety.

iii.

Multi-family ADUs. Applicant can select one of two options:

Option 1:

Conversion. Up to twenty-five percent of the existing multifamily dwelling units in a multifamily structure may convert any non-livable space to an ADU. Non-livable space includes storage rooms, boiler rooms, or parking. Under this option, at least one ADU shall be permitted regardless of the number of multifamily units. Thus, for a three unit multifamily structure, one ADU may be developed through conversion of non-livable space.

Option 2:

Alternatively, up to two detached ADUs may be constructed on a lot that has an existing or proposed multifamily structure, and shall be subject to a height limit of sixteen feet and side and rear yard setbacks of four feet.

c.

Floor Area Limits.

i.

Floor Area. The minimum size of an ADU or JADU shall be defined by the California Building Code. The maximum size shall be:

1.

Eight hundred fifty square feet for external ADUs with up to one bedroom or one thousand square feet for external ADUs with more than one bedroom where the proposed ADU does not comply with the setbacks of the base zoning district and special setbacks applicable to the parcel.

2.

Twelve hundred square feet for external ADUs where the proposed ADU complies with the setbacks of the base zoning district and special setbacks applicable to the parcel, on parcels smaller than three and one-half acres in size.

3.

Fifteen hundred square feet for external ADUs where the proposed ADU complies with the setbacks of the base zoning district and special setbacks applicable to the parcel on parcels three and one-half acres or larger in size. If such parcel also contains an interior ADU, the maximum floor area limit of the external ADU shall not exceed twelve hundred square feet.

4.

Seventeen hundred square feet for internal ADUs on all parcel sizes.

5.

Five hundred square feet for JADUs on all parcel sizes.

ii.

Percentage. An external ADU shall be additionally limited to fifty percent of the floor area of the existing or concurrently proposed main building, except as necessary to enable an ADU up to eight hundred and fifty square feet for external ADUs with up to one bedroom or one thousand square feet for external ADUs with more than one bedroom.

iii.

Adjusted Maximum Floor Area (AMFA) and Floor Area Ratio. ADU and JADU floor area shall be limited to the maximums described at subsections 4.c.i.2—5 or the floor area allowed by the base zoning district, whichever is more restrictive.

d.

Floor Area—Calculations.

i.

Basements. Space which meets the definition of a basement (Section 18.04.065), whether under a main residence or an ADU, shall not be included in AMFA calculations. However, floor area maximums at Section 18.36.040.B.4.c and review authority at Section 18.36.040.B.6 shall both apply to basement floor area that is part of an ADU. Basements located under an ADU that do not have internal access to the ADU are discouraged and shall be counted towards AMFA calculations.

ii.

Covered parking provided for ADUs shall be included in site AMFA calculations.

e.

Height. The maximum height for any type of ADU shall be:

i.

Sixteen feet vertical height and sixteen feet maximum height for an external ADU subject to ministerial review where the setbacks are less than those of the base zoning district.

ii.

Eighteen feet vertical height and twenty-four feet maximum height and shall be subject to ministerial review where the setbacks comply with those of the base zoning district. This includes daylight planes, where applicable.

iii.

More than eighteen feet vertical height or twenty-four feet maximum height, where allowed by the base zoning district, and shall be subject to staff discretionary review.

f.

Parking and Driveways.

i.

Parking Requirement. JADUs and internal ADUs shall not require any dedicated parking spaces. External ADUs shall require one dedicated parking space, as follows:

1.

ADU parking may be located in a covered or uncovered space, in tandem with other parking, and/or in setbacks.

2.

Parking space design shall conform to Section 18.60.020, parking, dimensions and access.

3.

On parcels of one acre or larger where an ADU of twelve hundred square feet or less is proposed, ADU parking is not required to be dedicated. The ADU parking space may be shared, or overlap with, one guest parking space, provided the property is compliant with the current parking requirements in this title.

4.

When a garage, carport or covered parking structure is demolished in conjunction with the construction of an ADU, or converted to an ADU, the parking spaces for the main unit do not need to be replaced.

ii.

Driveways. All driveways shall conform to Section 15.12.300, except the ASCC may grant an exception to the requirement that properties only have one entrance from the road and approve a second driveway when it is able to make the following findings:

1.

It is not feasible for the ADU to be served by the same driveway that serves the main building, taking into consideration the cost, topography and natural landscape, among other things.

2.

Providing a separate driveway for the ADU will result in less impervious surface for the property than would extending the existing driveway.

3.

It is shown that the proposed driveway:

a.

Does not exit onto a scenic corridor or cross a trail, as mapped by the town; and

b.

Provides for safe movements for all users, as determined by the public works director.

g.

Materials.

i.

Exterior materials shall be in a natural color palette reflective of the local environment.

ii.

Color reflectivity values shall not exceed forty percent, except that trim colors and roofs shall not exceed fifty percent reflectivity.

h.

Landscaping. Landscape plantings shall be selected from the town's list of approved native plants and shall adhere to the town's landscaping guidelines, as described in the design guidelines.

i.

Lighting. All lighting shall comply with Section 18.36.040.A.8, outdoor lighting.

j.

Setbacks.

i.

No setback shall be required for an existing garage that is converted to an accessory dwelling unit. This shall apply to both conforming and legal non-conforming garages. Non-conforming garages may not be expanded unless otherwise permitted by this section or state law.

ii.

Internal ADUs shall have sufficient side and rear setbacks for fire safety.

iii.

A setback of four feet from the side and rear lot lines shall be required for an external ADU of up to eight hundred fifty square feet with up to one bedroom or one thousand square feet with more than one bedroom.

iv.

Any ADU in excess of eight hundred fifty square feet with up to one bedroom or one thousand square feet with more than one bedroom shall comply with the setbacks of the base zoning district.

v.

Regardless of the setbacks permitted by this subsection, all ADUs must comply with applicable health and safety setback requirements governing specific parcels, including but not limited to setbacks required for fire safety, emergency vehicle access, geology, seismic, creek, topography, and other similar public health and safety considerations.

vi.

ADUs that do not comply with the setbacks of the base zoning district or applicable parcel setbacks, whether through new construction or by conversion of an existing structure, are subject to the following restrictions: 1) on sides of the structure within the required setback(s) there may be no exterior lighting, no egress windows or doors, and no portion of the windows and/or skylights shall be above nine feet in height 2) windows in required setbacks must consist of obscured glass to promote privacy between neighbors; 3) the ADU may not have a second driveway; 4) the ADU may not have any associated improvements/amenities such as a patio, deck, pool, fire pit, trellis, or sauna; 5) no basement shall be permitted; 6) fire safe landscape screening must be planted and maintained to minimize the visual impact to the neighbors.

vii.

For the purposes of this section, if any of the property boundaries are within or adjacent to an open space, road, trail, utility or similar easement running the length or width of the property boundary, the setback shall be measured from the edge of the easement located on the property.

k.

Second Address. ADUs may be assigned a separate address at the property owner's request, with the exception that any ADU with an approved second driveway shall always be assigned a second address. Applicants requesting an address shall submit an application as part of the building permit submittal. The planning and building director, in consultation with Woodside Fire Protection District, shall review and approve applications.

l.

Utilities. When visible from the public right-of-way, utilities installed to serve an ADU shall be grouped with any existing infrastructure for the main building and screened to the extent feasible, as determined by the planning and building director. In determining feasibility, the planning and building director may consider cost, topography, and the natural landscape.

i.

Utility Undergrounding. Utilities shall be required to be placed underground, as described in Section 18.36.010.B, with the following exceptions for ADUs:

1.

An internal ADU and any associated electrical service increases shall not trigger undergrounding of utilities.

2.

A detached ADU shall always underground utilities between the main house and the ADU, when connecting from the main house.

ii.

Any other instance of new construction for an external ADU shall require undergrounding as stipulated in Section 18.36.010.B relating to utility undergrounding, with the exception that an applicant may apply to the ASCC for relief from these requirements, as well as the undergrounding requirement for detached ADUs at subsection 4.k.i.2, and if the ASCC thereafter finds that undergrounding is not feasible or practicable, or that there is no reasonable alternative location for the related equipment, such undergrounding requirement shall not apply. Significant financial costs, topography, and natural landscape may be included in this consideration.

m.

Building Codes. ADUs must comply with applicable building code requirements, including fire sprinkler requirements, unless a modification or waiver of the fire sprinkler requirement is approved by the fire marshal. An ADU created by the conversion of existing interior space shall not be required to provide fire sprinklers if sprinklers are not required for the main residence.

5.

Types of Review.

a.

Ministerial Review. Ministerial review shall be completed by the planning and building director or her/his qualified designee under the building permit review process. No public hearings or noticing are required as part of this review; however, the applicant shall provide notice to all adjacent neighbors as part of the application process on a form approved by the director of planning. An ADU or JADU application which qualifies for ministerial review shall be acted upon within sixty days of the date the town receives a completed application. An ADU or JADU application made pursuant to an application for a main building may be delayed until a decision is made on the permit application to create the new main building.

b.

Discretionary Review.

i.

Discretionary review shall be conducted by one of the following review bodies:

1.

The planning and building director shall complete staff discretionary review in consultation with an ASCC member. The director may refer items directly to the ASCC when in her/his opinion the public interest would be better served by having the ASCC conduct the review.

2.

ASCC review is a discretionary review completed by the full ASCC at a noticed meeting.

ii.

Findings for Approval. The review body must be able to make all of the following findings in order to approve an ADU subject to discretionary review:

1.

The structure is designed so as to minimize disturbance to the natural terrain;

2.

Existing vegetation is preserved to the maximum extent possible;

3.

The structure is designed and located to allow adequate light and air for itself and its neighbors;

4.

Landscaping, screening and fencing preserve privacy and mitigate adverse effects on neighboring properties;

5.

Entrances, exits and internal circulation shall be sited to promote traffic safety and ease and convenience of movement;

6.

Night lighting is located and fixtures chosen to promote public safety but minimize effects on adjoining properties;

7.

Planting and site design mitigate the problems of drainage and soil erosion;

8.

Materials and colors are compatible with the rural setting of the town and the surrounding landscape and structures;

9.

Proposed grading minimizes the apparent disturbance to the natural terrain;

10.

The project is consistent with the Portola Valley Design Guidelines;

11.

The physical position, massing, and architectural design of the ADU reflect that it is accessory in nature and holds a subservient position to the main building;

12.

The design of the ADU and its ingress/egress reflect their physical positions on the property, such that units on or adjacent to setbacks are designed to minimize impacts toward adjacent properties.

iii.

Notice. Minimum noticing for ADUs requiring discretionary review shall include:

1.

Noticing to adjacent neighbors by the applicant, as required by the planning and building director in a form consistent with application materials published to the town website.

2.

Noticing as described by Section 18.64.085, ASCC - notification.

c.

An ADU application which is dependent on a septic tank and drain field shall be referred to and require approval of the county health officer in accordance with town policies.

d.

An ADU application which requires soil movement greater than fifty cubic yards or other work requiring a site development permit under Section 15.12.070 shall be referred to the town geologist, the town engineer, and any other review bodies necessary as determined by the planning and building director.

6.

Assignment of Review Responsibilities.

a.

Ministerial Review. State exemption ADUs authorized under Section 18.36.040.B.4.b above and ADUs which do not have any of the conditions listed in Section 18.36.040.B.6.b—d, below, shall be subject to ministerial review. All projects subject to ministerial review shall comply with all code requirements.

b.

Staff Discretionary Review. ADUs which do not have any of the conditions listed in Section 18.36.040.B.6.c., below, and which include any of the following shall be subject to staff discretionary review. However, any state authorized ADU defined in Section 18.36.040.B.4.b shall not be subject to discretionary review.

i.

An internal ADU larger than twelve hundred square feet or fifty percent of the existing building, whichever is less;

ii.

An ADU taller than eighteen feet in vertical height or twenty-four feet in maximum height;

iii.

An ADU with a light well larger than the minimum building code requirement;

iv.

An attached ADU which causes the main residence to exceed eighty-five percent of the adjusted maximum floor area (AMFA), except where the proposed ADU is up to eight hundred fifty square feet for external ADUs with up to one bedroom or one thousand square feet for external ADUs with more than one bedroom.

c.

ASCC Review. ADUs which include any of the following shall be subject to ASCC review. However, any state authorized ADU defined in Section 18.36.040 B.4.b shall not be subject to discretionary review.

i.

A separate driveway for the ADU.

ii.

Location in a non-residential zone.

iii.

Location on a property with historic resources, as identified in the historic resources element of the general plan, as provided for in Chapter 18.31, H-R (Historic Resources) Combining District Regulations..

d.

Geological Hazards. ADUs subject to Section 18.36.040(3)(b) (geologic safety exception) shall be subject to discretionary review consistent with Resolution No. 2746-2017, as may be amended from time to time.

7.

Additional Restrictions. In addition to the development standards described in this section, all ADUs and JADUs shall be subject to the following restrictions:

a.

Sold Separately. ADUs and JADUs shall not be sold separately from the main dwelling.

b.

Owner Occupancy. Where there is an ADU, either the ADU or the main building must be owner occupied. The other unit may be rented. ADUs approved between January 1, 2020 and December 24, 2024 are excepted from this requirement. Where there is a JADU, either the JADU or the main building must be owner occupied.

c.

Rental Restrictions. On properties where an ADU or JADU is present, any rentals of the ADU, JADU, or main building shall be for a term of thirty days or more.

8.

Administration.

a.

Appeals. A decision by the planning and building director or ASCC on an ADU may be appealed, if the appeal is filed within fifteen days of the decision.

i.

A decision made by the planning and building director is appealable to the ASCC.

ii.

A decision made by the ASCC is appealable to the planning commission.

b.

Implementation. The town council authorizes the planning and building director to establish permit application requirements, forms, and checklists that the director finds necessary or useful for processing any applications governed by this chapter and to adopt administrative guidelines to assist in the implementation of this chapter.

(Ord. 2021-438, § 1, 2021; Ord. 2019-431, § 2, 2019; Ord. 2018-424, § 1, 2018; Ord. 1991-266 §§ 1 (part), 2, 1992: Ord. 1988-242 § 3 (Exh. B) (part), 1988: Ord. 1987-219 § 2, 1987: Ord. 1979-166 § 17, 1979; Ord. 1976-145 § 2, 1976: Ord. 1967-80 § 1 (6303), 1967)