National City ADU Handbook (Mar 2024)

ADU HANDBOOK Source: Ohana MARCH 2024

ADU Handbook TABLE OF CONTENTS Overview 04 Introduction 05 ADU Types 06 ADU Standards 11 Steps to Build 13 Contacts 16 Potential Costs 17 Renting an ADU 18 FAQs 20 Resources 22 3

ADU Handbook Overview Source: Home Builder Digest The purpose of this handbook is to assist homeowners of the City of National City with understanding what an Accessory Dwelling Unit (ADU) is and whether one can be built on their property. This handbook also provides preliminary answers to key questions and shows the steps the City will require, and what the design and construction of an ADU will entail. How to Use This ADU Handbook Use this handbook as a guide to get started and to prepare the basic information you will need to give to the City, your lender, your designer, and your contractor. When you have taken photographs, measured your backyard, and sketched your idea for an ADU, as this handbook illustrates, you will be well on your way. There are architects, builders, and planners ready to help you at every stage. If you need additional information or have questions beyond this handbook, please refer to the Contacts section of this handbook for contact information for the Building and Planning Divisions.

To reference the City’s ADU Ordinance, please see Chapter 18.30.380Chapter 18.30.380 of the National City Municipal Codeof the National City Municipal Code. 4

ADU Handbook Introduction What is the Law for ADUs in What is an ADU? California? An Accessory Dwelling Unit (ADU) is a residential unit that can be added to a lot California Government Code Section with an existing single-family or multifamily 65852.150 declares that California is dwelling. ADUs can be detached (a facing a severe housing crisis and ADUs separate building in a backyard), attached are a valuable form of housing and can to or part of the primary residence, or a play a key role in meeting the housings garage conversion. ADUs are independent needs in many communities. The law housing units that have their own kitchens, recognizes that ADUs can provide bathrooms, living areas, and entrances. housing to individuals at an affordable cost within existing neighborhoods without the need to subdivide land to Why build an ADU? create new parcels. There are many reasons for building an ADU In 2017, the State Legislature passed on your lot. ADUs can provide additional a series of bills that allowed ADUs space for renters, grown children, elderly by-right* and created statewide

parents, or caregivers. “Empty nesters” development standards that regulated can stay in their neighborhood by moving size, setbacks†, height, and parking into a smaller ADU and renting their larger requirements (among other things) for existing home for additional income. An ADUs in all California cities. In 2019, ADU can be built to house a relative or the State Legislature passed another caregiver to be near one another while series of bills that refined guidance on maintaining privacy. ADUs. The City of National City has adopted its own ADU ordinance to comply with all the aspects of the State law to encourage the development of ADUs. To read the ordinance, see ChapterChapter 18.30.38018.30.380 of the National City Municipal Code. *Allowing something ‘by-right’ means that projects complying with zoning and regulations can be approved without the need for special permits, hearings, or conditions. By-right approvals are processed ministerially, or administratively, meaning without the need for discretionary approval. †Minimum required distance from the

property line to the structure. Source: Maxable 5

ADU Handbook ADU Types See what type of ADU you want to build and refer to that page to learn more: Detached ADU See Page 7 I have a single-family house I want to add an ADU in my The lot with a detached backyard and it will not share a ADU in the backyard: wall with the house + = Attached ADU See Page 8 I have a single-family house I want to add an ADU and the The lot with an ADU unit will share at least one wall attached to the house: with the house + = Conversion ADU See Page 9 I have a single-family house I would like to convert my The lot with a garage with a garage (attached or garage into an ADU converted to an ADU: detached) + = Junior ADU (JADU) See Page 10 I have a single-family house I want to convert a portion of The lot with a JADU: the house into a small ADU + = 6

ADU Handbook Detached ADU What It Is Detached ADU Requirements A detached ADU is a physically separated Floor Area unit from the single-family home or Minimum size: 150 square feet. multi-family home. This is the classic Maximum size: 1,200 square feet, ‘backyard home’ that most people are unless ADU is constructed within familiar with. This type of ADU is the the footprint of existing dwelling or most flexible and allows for the greatest detached structure, then there is no range of design options, given that it maximum. is essentially a new freestanding home. Refer to Section 18.30.380 (F)(8)Section 18.30.380 (F)(8) of the However, it is the most expensive of National City Municipal Code. the ADU type and typically has more Height complexity during permitting and Not to exceed height of primary construction due to factors such as the dwelling or 16 feet, whichever is installation of new water, sewer, and greater. If property is within 1/2 electrical connections to the street and/ mile of public transit height cannot or overhead power lines. exceed 18 feet. For properties with

What It May Look Like multi-family dwellings, height cannot exceed 16 feet, unless it is two stories high, then 18 feet. If ADU is above the footprint of a detached garage, two stories is allowed. Refer to Section 18.30.380 (F)(4)Section 18.30.380 (F)(4) of the National City Municipal Code and California Government Code SectionGovernment Code Section 65852.2(c)(2)(D)65852.2(c)(2)(D). Setback Front: Minimum 15 foot setback. Sides: Minimum 4 foot setback. Rear: Minimum 4 foot setback. Refer to Section 18.30.380 (F)(5)Section 18.30.380 (F)(5) of the National City Municipal Code. Parking Not required. Refer to Section 18.30.380 (F)(3)Section 18.30.380 (F)(3) of the Source: City of San Jose Planning Department National City Municipal Code. 7

ADU Handbook Attached ADU What It Is Attached ADU Requirements An attached ADU is a unit attached to Floor Area the primary home. While construction Minimum size: 150 square feet. costs are comparable to a detached Maximum size: 50% of main ADU because it is all new construction, dwelling unit or 1,200 square feet, these units typically provide cost savings whichever is greater. with utility connections which can be Refer to Section 18.30.380 (F)(8)Section 18.30.380 (F)(8) of the connected directly through the primary National City Municipal Code. residence (versus creation of new water, Height sewer, and electrical connections to the street and/or overhead power lines). Cannot exceed the height of Attached ADUs are also typically limited the primary structure or 16 feet, in size to 50% of the total floor area of whichever is greater. If ADU is the primary residence. constructed above a garage or on a lot smaller than 5,000 square feet, What It May Look Like height shall not exceed twenty-five feet. Refer to Section 18.30.380 (F)(4)Section 18.30.380 (F)(4) of the

National City Municipal Code. Setback Front: Minimum 15 foot setback. Sides: Minimum 4 foot setback. Rear: Minimum 4 foot setback. Refer to Section 18.30.380 (F)(5)Section 18.30.380 (F)(5) of the National City Municipal Code. Parking Not required. Refer to Section 18.30.380 (F)(3)Section 18.30.380 (F)(3) of the National City Municipal Code. Source: Housable 8

ADU Handbook Conversion ADU What It Is Conversion ADU Requirements A conversion ADU is when existing Floor Area & Height structure—such as a garage or accessory If detached conversion, see page 7. structure—is converted into an ADU. If attached conversion, see page 8. Conversion ADUs are the most cost- effective approach to designing, Setback permitting, and building an ADU, Front: Minimum 15 foot setback. because homeowners are typically able Sides: Minimum 4 foot setback. to use existing foundations, framing, Rear: Minimum 4 foot setback. roof systems, and plumbing/electrical Refer to Section 18.30.380 (F)(5)Section 18.30.380 (F)(5) of the National City Municipal Code. systems. Additionally, permitting fees are generally lower. However, the ADU is Parking limited to the size/configuration of the Not required. existing structure and therefore design Refer to Section 18.30.380 (F)(3)Section 18.30.380 (F)(3) of the options can be more limited compared National City Municipal Code. to new construction. Before and After Conversion What It May Look Like Source: Housable Source: Housable

ADU Handbook Junior ADU What It Is JADU Requirements A Junior ADU (JADU) is a smaller type Floor Area of ADU which is limited to 500 square Minimum size: 150 square feet. feet and must be a conversion of Maximum size: 500 square feet. For existing space that is contained entirely JADUs within an existing structure, within an existing or proposed single- an additional 150 square feet for family residence with a separate entry. ingress and egress only. Garages and other non-living spaces Refer to Section 18.30.390(F)Section 18.30.390(F) of the may be converted to a JADU, if they National City Municipal Code. are attached to the primary residence. Height JADUs are allowed in addition to ADUs, therefore it is possible to build a total of Not applicable as a JADU has to two additional units on one single-family be contained within the walls of property. existing or proposed single-family JADUs are limited to one per lot with a home. single-family residence. Lots with multiple Setback detached single-family dwellings are not Not applicable. eligible to have JADUs. In addition, JADUs

Parking are not allowed within detached ADUs. Not required. What It May Look Like Refer to Section 18.30.390(F)Section 18.30.390(F) of the National City Municipal Code. Source: Maxable 10

ADU Handbook ADU Standards The information presented below Design Standards summarizes additional Development and Architectural Characteristics Design Standards listed in the City of Your new ADU should incorporate National City’s ordinance not previously the distinctive architectural mentioned. For the full updated list of characteristics of surrounding the City’s Development Standards for development, for example: window ADUs, please see Section 18.30.380Section 18.30.380 of and door detailing, decoration, the National City Municipal Code. For materials, roof style and pitch, Residential Building Design Standards, finished-floor height, porches, see Section 18.42.070 (C)Section 18.42.070 (C). If there are any bay windows, dormers, chimneys, discrepancies between standards found balconies, shutters, decorative on this handbook and National City’s molding, and similar architectural Municipal Code, the latest standards details. found in the Municipal Code shall prevail. Exterior Materials Exterior materials, window details, Development Standards and colors of building additions

Number of ADUs should match those of the main For single-family dwellings, one ADU structure. and one JADU are permitted. For multi- Fire Sprinkler System family dwellings, up to two detached ADUs and at least one interior ADU are According to the municipal code, permitted (up to 25% of the number new ADUs are not required to of existing units in the multi-family provide fire sprinklers if they are not dwelling). Please refer to the California required for the primary residence. Government Code Section 65852.2 (e)Government Code Section 65852.2 (e) and In addition, the California ResidentialCalifornia Residential Chapter 18.30.380 (D)Chapter 18.30.380 (D) of National City’s Code Section R313.2Code Section R313.2 (Part 3 of Title Municipal Code. 24) requires that newly constructed one- and two-family dwellings install Landscaping automatic residential sprinkler One 24-inch box tree should be systems. To learn more about this planted within the required 15 foot requirement please see CaliforniaCalifornia front yard setback for ADUs or in the

Department of Forestry and FireDepartment of Forestry and Fire abutting parkway. Existing trees at Protection’s Information Bulletin 21-Protection’s Information Bulletin 21- least 15 feet high and 15 feet wide 005005, beginning on bottom of page 2. satisfy this requirement. 11

ADU Handbook and approvals. If your property Fire Hose Pull Measurement currently has a septic system instead The Fire Department requires a hose of a sewer connection, known as line measurement, starting from the an Onsite Wastewater Treatment edge of the curb to the farthest point System (OWTS), it is strongly of the ADU, not to exceed 150 feet in recommended that you obtain length. The measurement is required approval of your septic system prior in order confirm the Fire Department to expending funds for a final set hose can properly cover all sides on the of architectural plans for your ADU. ADU in the event of a fire. Keep this The San Diego County Department requirement in mind when planning of Environmental Health & Quality your ADU. (DEHQ) has oversight of all septic Engineering Standards systems, even those within National Site Considerations City boundaries. The configuration and location of your Other Utilities proposed ADU on your parcel may Your ADU project may require necessitate a more thorough review of coordination with other utilities, your project.

In some cases, an ADU including those that provide project will require an Engineering water, gas, electricity, and Permit, separate from the Building telecommunications services. Permit. Upon submittal to the Building Sweetwater Authority, the water Division, your plans will undergo agency serving National City, an initial review by the Engineering has created a brochure titled Division. Your site-specific requirements “Application Guide for ConcurrentApplication Guide for Concurrent will be identified at that first step Review with Land Use AgencyReview with Land Use Agency” to in the process. Considerations that help guide you in the submittal typically trigger additional review and and construction process. You are approvals include floor elevations, encouraged to also reach out to San drainage, slopes and grading, Diego Gas & Electric (SDG&E) early foundation type (slab on grade vs. on in the process as they may have raised footing), work in the right- other disconnection, re-connection, of-way such as sidewalk or driveway and new service requirements that

changes, and new sewer connections. could have both time and cost Sewer Connection implications. The majority of properties in National City are connected to the municipal sewer system, and review of your existing sewer lateral connection as well as payment of capacity fees will be required as part of your permits 12

ADU Handbook Steps to Build There are many steps involved when building an ADU. The following two pages details steps to take in four phases: Confirm Eligibility and Allowed Size of ADU •• Determine the eligibility of your property and the maximum size ADU you can build. Refer to Chapter 18.30.380Chapter 18.30.380 of the National City Municipal Code. •• Utilize ADU finance tools (see Resources section) to estimate your costs. Pre- •• Call or e-mail the Planning Division (see Contacts section) to Application discuss options as well as any zoning constraints or site- specific factors. This step will help to avoid surprises after Phase investing time and money into a building design. The Planning Division may refer you additional City Departments to further discuss your proposal. •• If applicable, submit an application at the Sweetwater Authority. The submittal process takes approximately 6 weeks. Please see their “Application Guide for Concurrent Review withApplication Guide for Concurrent Review with Land Use AgencyLand Use Agency” for more information. Design and Preparation

•• Decide if you will build a new ADU or convert an existing structure to an ADU. Refer to Resources section for guidance and examples. •• Consider your options for drafting plans such as hiring a designer or architect, drawing your own plans, purchasing plans, or purchasing a prefabricated unit. Design •• Consider your options for construction. You can hire a General Phase Contractor to manage and complete the construction or obtain an owner/builder permit to allow you to manage and complete the project yourself or through sub-contractors. Note that your designer and/or contractor must obtain a National City Business License. Once you select an ADU design option, you can get an estimate of City fees by looking up the Development feesDevelopment fees. You can also see the ADU Application Checklist for a list of submittal requirements. 13

ADU Handbook Submit Plans for Building Permit •• Depending on the type, size, height of your desired ADU, your building permit application may need a few rounds of comments and/or re-submittals. Plans are typically reviewed by various agencies, such as planning, engineering, and fire districts. Expect this process to take several weeks. •• The plans must have accurate information in order for the submittal to be accepted. Make sure to address the following items, which tend to be overlooked: - List the current applicable codes on the cover sheet (2022 Building Code cycle). - Establish a new address for the new ADU and be included on the plans. - Identify the accurate square footage of the proposed ADU in the scope of work and project data. •• You can reference the City’s Information Guide for Plan Check,Information Guide for Plan Check, Building Permits, and InspectionsBuilding Permits, and Inspections for further information on ensuring the plans and application are complete. Permitting Obtain Permits and Pay Fees Phase •• The building permit can be obtained by a licensed contractor

or as an owner-builder, meaning the property owner can obtain the permit. •• Once all the preliminary conditions and requirements have been met with the respective departments, the plans are approved through the plan check process, and the final permit fees have been paid, the permit will be ready for issuance. •• Pay all fees as required. The fees for an ADU permit are broken down into three types: - Plan Check Fees: These must be paid at the time of application submission and cover the cost of the plan check review. - Impact Fees: These must be paid prior to permit issuance and are based on the square footage of the structure. Impact fees are not required for ADUs that are under 750 square feet. - Permit Fees: These must be paid prior to permit issuance and cover the cost of permitting staff, inspection staff, and administrative staff. 14

ADU Handbook Construct Your ADU •• Once the building permit has been issued, you may begin the construction of the ADU. The permit, inspection record, and approved set of plans should remain on the job site for inspections. •• Inspections are required for each section of the construction phase (i.e. Foundation, Framing, Plumbing, Electrical, Mechanical etc.). To schedule inspections, you need to call 619-336-4363. Construct •• You may reference our Building Inspections PageBuilding Inspections Page for more information. & Occupy •• If for any reason the completed construction differs from Phase the approved set of plans, you will be required to either correct the completed construction or revise the approved set of plans which would require submitting new plans for plan check. Occupy Your ADU •• Once the construction phase is complete and you have received approval of the Building Division’s final inspection, you are able to occupy the ADU. •• If you want to rent your new ADU, see page 18 for more information. 15

ADU Handbook Contacts Building Division - City of National City building@nationalcityca.gov 1-619-336-4210 https://www.nationalcityca.gov/government/community-development/building Planning Division - City of National City planning@nationalcityca.gov 1-619-336-4310 https://www.nationalcityca.gov/government/community-development/planning Engineering Division - City of National City engineering@nationalcityca.gov 1-619-336-4380 https://www.nationalcityca.gov/government/engineering-public-works/ engineering-division Fire Prevention Division - City of National City rhernandez@nationalcityca.gov 1-619-336-4550 https://www.nationalcityca.gov/government/fire/fire-prevention Sweetwater Authority 1-619-420-1413 https://www.sweetwater.org San Diego Gas & Electric https://www.sdge.com Department of Environmental Health & Quality - San Diego County 1-858-565-5173 https://www.sandiegocounty.gov/deh/ 16

ADU Handbook Potential Costs To determine the costs for constructing your ADU you will need to estimate the costs to obtain a Building Permit (and other necessary permits), costs to design your ADU, hard costs (e.g., building construction, sewer or septic upgrade, and site improvements) and soft costs (e.g., design costs and study costs, such as septic analysis). In addition, you will want to also estimate the rental income amount, if you plan to rent your ADU. We have provided links to useful and free cost estimator tools on the Resources section. Below are some rules of thumb to follow as you calculate ADU costs: •• New construction is typically 125% more expensive than conversions (assuming the structure to be converted is in good physical condition). •• The bigger the ADU, the more expensive—but less expensive on a per square foot basis. In other words, each additional square foot you add has a marginally decreasing cost. •• The higher the quality of the fixtures and finishes, the more expensive the ADU.

•• Separately metered utilities (water, electrical, gas) cost more than using existing utility lines and supplemental permits are required. •• Building on slopes or hillsides adds significant additional cost. •• New detached ADUs are required to have solar systems, which should be considered in overall project costs. Source: United Dwelling 17

ADU Handbook Renting an ADU Do I want to be a landlord? Not everyone is ready to be a landlord. With an ADU on your property you can rent your ADU for long-term use but, you cannot rent the ADU as a short-term vacation rental (for a period of less than 30 days). If you plan to rent, it is crucial you understand what your landlord responsibilities will be. Renting your ADU means you are sharing your property with another household who has tenancy rights and the right to expect quiet enjoyment of the home for which they are paying rent. Additionally, as a landlord, you are subject to all of the same requirements under local, State and federal law, such as non-discrimination and the requirement to give notice of changes to the lease. To learn more about your responsibilities, check out “A Guide to Residential Tenants’ and Landlords’ Rights and“A Guide to Residential Tenants’ and Landlords’ Rights and Responsibilities”Responsibilities”. Lease Agreements A legally enforceable lease describes both landlord and tenant expectations. A lease

dictates what will make sharing your property work for you—for example, will you allow your tenant to smoke in the unit? If not, be sure the lease agreement states that very clearly. Will you allow pets? If so, think about the number, type and size that will be acceptable and spell it out in the lease. What are your expectations for guests? Where will the tenant park? You should plan to inspect the unit once a year to be sure everything is in working order, such as the smoke alarm—be sure the lease makes it clear you will do this and how you will give notice to the tenant when you plan to enter the unit. There are many resources available for landlords and you are encouraged to seek help from organizations that can inform you of the most up-to-date, legally enforceable list of typical lease conditions (some are listed on the Resources section). You can also build and customize your lease for free on various websites including Zillow RentalZillow Rental ManagerManager. Selecting Tenants When selecting tenants, landlords must adhere to federal Fair Housing laws that may apply.

The State of California Civil Rights Department provides more information on Housing DiscriminationHousing Discrimination. When considering tenant applications, you may encounter potential renters that participate in the Housing Choice Voucher program. This is a program managed by the Federal Department of Housing and Urban Development. 18

ADU Handbook (HUD), and has several potential advantages to you as a landlord. You several potential advantages to you as a landlord. You can find more information about this program and how landlords benefit from it at the Housing Authority of the County ofHousing Authority of the County of San Bernardino’s website.San Bernardino’s website. Setting Rent Levels To determine the “right” rent you should charge for your ADU, start by finding out what the current market is charging. To do so, you can search for “average rent” on the internet and compare similar rental price listings. You can also check HUD’s HOMEHUD’s HOME Rent LimitsRent Limits for your city, which publishes Fair Market Rent every year. When deciding on how much you will charge to rent your ADU, you may also want to think about how much income you need in order to cover your costs and pay down any debt you acquired. 19

ADU Handbook FAQs Where can I find the most updated information about current ordinance on ADUs? Chapter 18.30.380Chapter 18.30.380 Accessory Dwelling Units (ADUs) and Chapter 18.30.390Chapter 18.30.390 Junior Accessory Dwelling Units (JADUs) of the National City Municipal Code. Who can I talk to for ADU-related planning questions? You can contact the City of National City’s Planning Division. Please see the Contacts section for contact information. Can I build more than one ADU? Yes, two detached ADUs are permitted on a lot with a multi-residential use if the lot includes an existing multi-family residential property and each ADU does not exceed 1,200 square feet in total floor area and 16 feet in height. Multiple ADUs are permitted within the portions of existing multi-family residential structures that are not used as livable space—such as storage rooms, basements or garages—if each unit complies with state building standards. Moreover, at least one ADU is permitted within an existing multi-family residential structures and up to twenty-five percent of

the existing number of multi-family dwelling units is allowed. See Chapter 18.30.380 (D) of the National City Municipal Code. My property is on septic. Can I still build an ADU? Consult with the Department of Environmental Health and Quality (DEHQ) early in the process. Although ADUs are allowed on any parcel with a single-family home, all performance standards for sanitation must be met and approved. In the event that your OWTS does not meet capacity or performance standards, you will need to work with the Engineering Division for the proper review and approval to install a new service lateral that connects to the municipal sewer system. How big can I make my ADU? The allowable size of an ADU is dependent on the type being proposed. Specifically, whether the ADU is attached to the existing house or detached. If the ADU is attached to the existing house, it cannot be bigger than 50% of the existing house or 1,200 square feet, whichever is less. If the ADU is detached, then it can be no larger than 1,200 square feet in size. 20

ADU Handbook Will adding an ADU raise my property taxes? ADUs/JADUs will be assessed by San Diego County at their current valuation. However, existing square footage which is not touched by the project will not be re- assessed. Do I need to live on the property to build an ADU? There is no owner-occupancy requirement for an ADU. However, there is an owner- occupancy requirement for a JADU. Can my ADU be used as a short-term rental? No. ADUs/JADUs, including those on multi-family properties, must be rented for a period exceeding 31 days. Can I sell my ADU separately from my primary unit? The ADU may not be sold or otherwise conveyed separate from the primary residence. 21

ADU Handbook Resources The following are external resources providing additional information to help you navigate the ADU process: • HCD ADU WebsiteHCD ADU Website • Symbium National City ADUSymbium National City ADU Provides links to various resources on A free one-stop resource for ADUs ADUs, including an ADU handbook in your city to find pertinent published by the California Housing information about your property and Community Development and sketch ADU designs that fit Department. your property. • Casita CoalitionCasita Coalition • California Apartment AssociationCalifornia Apartment Association -- Provides guidebooks for homeowners Rental/Lease Agreement WebinarRental/Lease Agreement Webinar on building and financing an ADU. On-demand class that covers various California laws that regulate • California Housing Finance AgencyCalifornia Housing Finance Agency landlord/tenant relationships. State agency providing opportunities for ADU projects via third-party lending. • MaxableMaxable Offers free ADU tools and guides including a cost estimator tool as well as an e-ADU course.

• Accessory DwellingsAccessory Dwellings A clearinghouse for ADU trends, data, and best practices. • ADU Educational WorkshopADU Educational Workshop Virtual ADU educational workshops, including planning, permitting, building, financing, and property management. • Second Unit InspirationSecond Unit Inspiration An idea booklet on ADUs with sample floor plans. 22