Laws
March 20, 2024

ADU Laws and Regulations in San Diego - 2024

Steadily's blog cover page for information around landlord insurance.

Understanding ADU Basics in San Diego

In San Diego, accessory dwelling units (ADUs) offer homeowners a way to maximize property space and contribute to the mitigation of housing shortages. This section will provide a detailed look into what ADUs are, their types, and the specific regulations governing them within the city.

Definition of Accessory Dwelling Units

An Accessory Dwelling Unit is a secondary housing unit on a single-family residential lot. It's allowed regardless of when the primary residence was built, and the unit can be used for rental purposes or to house family members. San Diego has recognized ADUs as a critical component in addressing the local housing crisis by providing affordable housing options.

Detached vs. Attached ADU Characteristics

Detached and attached ADUs differ primarily in their physical connection to the primary residence:

  • Detached ADU: Stands as a separate structure from the primary house. Deemed more private, it typically involves a distinct construction process, offering a clear separation of living spaces.
  • Attached ADU: Shares at least one wall with the main home. It can be cost-effective since it utilizes existing structures, and it may require less exterior work than a detached unit.

Each has its benefits and challenges, and homeowners must comply with specific building regulations set by the city.

Junior ADU Features and Regulations

A Junior Accessory Dwelling Unit (JADU) is a smaller, self-contained living space created within the walls of an existing home. In San Diego, JADUs must be:

  • No more than 500 square feet in size.
  • Include an efficiency kitchen; bathrooms may be shared with the primary residence.

San Diego's laws allow for the creation of JADUs to further address housing flexibility and affordability, subject to complying with the local ordinances that regulate them.

Zoning Laws and Property Requirements in San Diego

In San Diego, Accessory Dwelling Units (ADUs) are subject to specific zoning laws and property requirements. They provide a means to address the housing affordability crisis by allowing homeowners to add living spaces to their properties.

Zoning Districts and ADU Compliance

San Diego's zoning regulations permit the construction of ADUs on lots that are zoned for both single-family and multi-family dwellings. Each zoning district has its own rules regarding the placement and development of ADUs. For example, a lot in a single-family zoning district with an existing or proposed single-family home may include both an ADU and a Junior ADU (JADU). It is crucial to ensure that the development complies with the local zoning requirements set by the city.

Setbacks and Living Space Limits

Setbacks are essential to consider when building an ADU. These are the minimum distances that structures must be located from property lines, roads, or other structures. In San Diego, the regulations stipulate specific setback measurements to maintain a sense of privacy for adjacent properties and to adhere to safety standards. Additionally, the living space of an ADU must be secondary in size to the primary residence on the property.

Maximum Size and Height Restrictions

San Diego imposes limits on the maximum size and height of ADUs to ensure they remain complementary to the existing neighborhood context. An ADU attached to the main residence can be up to 50% of the size of the single-family home with a maximum of 1,200 square feet. For detached ADUs, the maximum allowed size is 1,200 square feet, regardless of the primary residence's size. Height restrictions also apply and are subject to local zoning guidelines; therefore, it's important to consult the city's Municipal Code for precise measurements and possible exceptions.

Permitting Process for ADUs in San Diego

When building an Accessory Dwelling Unit (ADU) in San Diego, understanding the permitting process is crucial. This process ensures that construction complies with local regulations and safety standards.

Building Permit Essentials

To begin the ADU permit process, applicants must first obtain a building permit. This requires submitting detailed plans that illustrate the proposed ADU's layout, materials, structure, and compliance with the City's building codes. The City of San Diego mandates that ADUs be secondary to the primary dwelling in terms of size and that specific zoning requirements are met depending on whether the ADU is attached or detached.

Plan Checks and Information Bulletin 400

During the review phase, the City performs several plan checks to assess the project's compliance with local, state, and federal regulations. Information Bulletin 400 serves as a comprehensive guide, detailing critical elements such as setbacks, height limitations, parking requirements, and other necessary specifications for ADU construction in San Diego. It's imperative for builders and homeowners to familiarize themselves with this bulletin to avoid project delays or denials.

Permit Issuance and Inspection Phases

Once plan checks are approved, the permit issuance phase begins. A building permit is then granted, allowing construction to commence. Following permit issuance, there will be routine inspections throughout the building phase to ensure ongoing compliance. These inspections are vital steps in the process, leading to the final approval and official sign-off of the newly constructed ADU.

Financial Considerations and Incentives in San Diego

When considering building an Accessory Dwelling Unit (ADU) in San Diego, potential builders can benefit from understanding the nuances of financial requirements including impact fees, potential exemptions, and available financial assistance, as well as opportunities for support through grants and loans. Additionally, an ADU bonus program offers incentives aimed at promoting affordable housing.

Understanding Impact Fees and Exemptions

Impact fees are levied by the city to offset the costs of public services necessitated by new developments. San Diego's approach to ADUs includes certain exemptions and reductions in impact fees to encourage their construction. For example, ADUs under 750 square feet are exempt from impact fees, which can significantly reduce the overall cost of development.

For ADUs larger than this, fees may still apply, but they have been considerably reduced compared to standard residential development fees. Homeowners should closely review the current fee schedule for precise figures as these fees can vary depending on the specific characteristics of the project.

Grants and Loans for Financing ADU Construction

To facilitate the financing of ADU construction, the San Diego Housing Commission's (SDHC) ADU Finance Program provides financial assistance to homeowners. This assistance comes in the form of construction loans designed to make the addition of ADUs more attainable.

The program also offers technical assistance to shepherd homeowners through the process of building an ADU on their property. This kind of resource is particularly valuable for low-income homeowners who might otherwise find the process daunting and the expense prohibitive.

ADU Bonus Program and Affordable Housing

The ADU Bonus Program in San Diego is part of a wider effort to address the housing crisis by increasing the number of affordable rental units. By participating in this program, property owners can construct an affordable ADU and, in exchange, receive certain development incentives such as expedited permit processing and increased floor area ratios.

To qualify as affordable, these ADUs must be rented at or below prices affordable to low-income households, and these affordability conditions typically persist for a tenure of 15 years. This initiative reflects San Diego's push towards using ADUs as a method to expand the city's affordable housing stock.

Construction and Development Standards in San Diego

When it comes to construction and development of Accessory Dwelling Units (ADUs) in San Diego, adherence to general building codes and safety regulations is of utmost importance. These standards ensure that new constructions are both safe for occupants and compliant with state and local requirements. Careful selection of contractors and awareness of environmental considerations are also pivotal in the ADU development process.

General Building Codes and Safety Regulations

San Diego's approach to building an ADU mandates compliance with the California Building Code to ensure the safety and welfare of future occupants. This includes but is not limited to structural integrity, fire safety, utilities, and access. ADU projects must meet specific seismic, fire-resistance, and egress standards. A detailed summary of these conditions can be found on the City of San Diego Official Website.

Contractor Selection and Technical Assistance

Selecting the right contractor is crucial for a successful ADU project. Homeowners should seek contractors who are well-versed with San Diego’s ADU regulations to ensure a streamlined process. Technical assistance for homeowners, possibly including financial aid through construction loans, is available through the San Diego Housing Commission's ADU Finance Program, which assists in understanding and navigating the construction of ADUs.

Sustainable Development and Environmental Considerations

Sustainable development in San Diego’s ADUs means incorporating eco-friendly materials and practices. These may involve the use of renewable energy sources, water-efficient landscaping, and high-performing insulation to minimize environmental impact. Choosing sustainable options can position an ADU as part of a Sustainable Development Area, meeting higher standards for energy efficiency and resource conservation. Information about San Diego ADU regulations and fostering sustainable development can be explored through resources like Dwellito's comprehensive guide.

Special Conditions in San Diego

In San Diego, accessory dwelling units (ADUs) face unique regulatory frameworks due to the city's distinct landscape and historical fabric. The Coastal Regulation Considerations, historical districts, and more specific rules on parking and landscaping all influence ADU development.

Coastal Regulation Considerations

ADUs located within the Coastal Overlay Zone have to comply with both San Diego municipal regulations and the California Coastal Commission's guidelines. This dual oversight ensures that ADU development respects the coastal environment's delicate balance, often requiring additional review processes and adherence to specific aesthetic standards.

ADUs in Historical Districts and Overlay Zones

San Diego's historical districts and overlay zones come with a supplementary layer of regulation aimed at preserving the area's cultural and architectural heritage. Construction of ADUs in these areas must respect the existing character of neighborhoods, often necessitating designs that blend seamlessly with historic structures.

Parking Space Requirements and Landscape Considerations

San Diego has delineated parking requirements that may exempt ADUs from additional parking spaces if they are located within a half-mile radius of public transit. Moreover, landscape requirements in San Diego stipulate that any new construction, including ADUs, incorporate water-efficient landscaping, supporting the city's water conservation efforts and promoting sustainable development practices.

Ongoing Management and Use of ADUs in San Diego

Once established, Accessory Dwelling Units (ADUs) in San Diego offer homeowners versatility in property use but require adherence to specific guidelines for rental and residency. Different structures of ADUs can accommodate needs such as independent living facilities, while ongoing maintenance is pivotal to meet the standards set by the San Diego Municipal Code.

Rental Rules and Homeowner Residencies

Homeowners who build ADUs on their property can benefit from the additional rental income while contributing to the housing supply in San Diego. However, they must comply with certain restrictions; for instance, in many cases, the property owner must occupy either the primary residence or the ADU itself. This regulation is designed to maintain neighborhood stability and ensure the ADU is managed responsibly.

Structuring ADUs for Independent Living Facilities

ADUs can also provide ideal spaces for independent living facilities, a critical aspect for homeowners wishing to support relatives who require some level of autonomy. By constructing an ADU, homeowners can design these units to include accessibility features and tailored amenities that facilitate comfortable, independent living while still being close to family support.

Maintenance and Compliance with Municipal Code

Maintaining an ADU involves regular upkeep and ensuring that the dwelling continues to meet all requirements of the San Diego Municipal Code. Compliance with guidelines regarding size, location, and safety codes is not only a matter of legal adherence but also affects the well-being of occupants and the community. Homeowners are responsible for routine checks and updates to the property as per city ordinances.

Frequently Asked Questions

As regulations evolve, understanding the specifics of Accessory Dwelling Unit (ADU) requirements is crucial for homeowners and developers in San Diego. This section addresses common queries regarding ADU development to clarify San Diego's current rules and expectations.

What are the minimum size requirements for an ADU in San Diego?

The minimum size for an ADU in San Diego is 150 square feet. This size ensures that the unit is livable and can contain the necessary basic amenities.

Can I build an ADU on a property with an existing single-family home in San Diego?

Yes, properties zoned for single-family or multifamily use are allowed to develop one ADU and one Junior ADU (JADU) alongside an existing or proposed single-family dwelling. This supports the city's goal of increasing housing supply and affordability.

Are there any specific design standards an ADU must meet in San Diego?

San Diego has design guidelines intended to ensure that ADUs blend well with the neighborhood. These standards address aspects such as landscaping, architecture, and exterior materials to maintain a coherent community aesthetic.

What is the maximum allowable size for an ADU in San Diego?

The maximum size of an ADU is 1,200 square feet or 50% of the primary unit's living area, whichever is less. However, the actual size might be affected by other site-specific factors such as lot coverage and setback requirements.

How do the recent changes to state law affect ADU construction in San Diego?

Recent updates to California state law have sought to simplify the process and reduce barriers for the construction of ADUs. This includes eliminating certain fees, reducing parking requirements, and streamlining approval processes to encourage more ADU development.

What fees are associated with building an ADU in San Diego?

Building an ADU in San Diego involves various fees, such as development impact fees, construction permit fees, and utility fees. Thanks to new legislation, some fees, particularly those related to impact fees for smaller ADUs, have been reduced or waived to lower the cost of ADU construction.

This post is for informational purposes only and does not serve as legal, financial, or tax advice. Consult your own legal, financial, or tax advisor for matters mentioned here. The information on this site is general in nature. Any description of coverage is necessarily simplified. Whether a particular loss is covered depends on the specific facts and the provisions, exclusions and limits of the actual policy. Nothing on this site alters the terms or conditions of any of our policies. You should read the policy for a complete description of coverage. Coverage options, limits, discounts, deductibles and other features are subject to individuals meeting our underwriting criteria and state availability. Not all features available in all states. Discounts may not apply to all coverages. Steadily is not liable for any actions taken based on this information. If you believe any of this information may be inaccurate please contact us.

Download your free resource

Table of Contents

Get coverage in minutes

One of America's best-rated landlord insurance services. No hidden cancellation fees. Competitive rates nationwide.

Get a quote
Get Appointed

Delight your clients with one of America's best-rated landlord insurance services nationwide.

Apply Today

Video Library

View all videos

Other Resources

Get coverage in minutes

No hidden cancellation fees. Competitive rates nationwide.

    Thank you! Your submission has been received!
    Oops! Something went wrong while submitting the form.

    Get Appointed

    Become a Steadily appointed agent and start selling one of America's best-rated landlord insurance services.