Introduction to San Diego ADU Regulations

San Diego has become one of the most desirable cities in California, known for its beautiful coastline, vibrant culture, and growing real estate market. In recent years, one of the most popular trends in home construction is the addition of Accessory Dwelling Units (ADUs). These small, self-contained living spaces, often referred to as "granny flats" or "in-law suites," can offer homeowners additional living space or provide rental income.

However, before you start building your ADU, it’s important to understand San Diego’s ADU regulations and zoning laws to ensure your project complies with all local codes and ordinances. In this article, we will cover everything you need to know about ADUs in San Diego, including zoning rules, design guidelines, permits, and frequently asked questions.

What is an ADU (Accessory Dwelling Unit)?

An Accessory Dwelling Unit (ADU) is a secondary housing unit on a single-family residential lot. ADUs are typically detached from the primary home, but can also be attached or even converted from existing structures such as garages or basements. They offer a wide variety of uses, including:

• Rental Properties: An ADU can generate rental income for homeowners.

• Family Housing: ADUs provide a private space for family members, such as elderly parents or adult children.

• Home Office: An ADU can serve as a separate office for those working from home.

• Guest Accommodation: It can be used to host guests or offer short-term rentals.

San Diego ADU Zoning Laws

Zoning laws regulate how land can be used in specific areas and play a critical role in determining whether or not you can build an ADU on your property. In San Diego, the regulations regarding ADUs fall under the California statewide laws and the San Diego Municipal Code.

1. Zoning Districts Allowing ADUs

In San Diego, ADUs are permitted in most residential zones, including:

• Single-family residential zones (RS-1-7, RS-1-14, etc.)

• Multi-family residential zones (RM-1-1, RM-2-5, etc.)

However, the property must meet certain conditions, such as:

• The property should be a minimum size (varies based on zone).

• The property should have access to public utilities such as water, sewer, and electricity.

• The main house must also comply with zoning regulations.

2. ADU Size Requirements

San Diego's ADU size requirements depend on the type of ADU being built:

• Detached ADUs: The maximum allowable size is generally 1,200 square feet (although this can vary).

• Attached ADUs: They can be up to 50% of the existing home’s size, but no more than 1,200 square feet.

• Junior ADUs (JADUs): These smaller units can be up to 500 square feet and must be within the existing structure of the primary dwelling.

3. Setback Requirements

ADU setback regulations define how far the ADU must be from property boundaries. In most cases, the minimum setback for detached ADUs is 4 feet from rear and side property lines, but there are exceptions depending on the specific location and type of ADU.

San Diego ADU Design Guidelines

The design of your ADU needs to align with both functional and aesthetic considerations. Key design elements to keep in mind include:

• Architectural Consistency: The ADU should complement the design and style of the main residence. While it doesn’t need to be identical, it should be visually cohesive.

• Privacy: Ensure that windows and doors are placed to respect the privacy of neighboring properties.

• Landscaping: Landscaping is important for ensuring that the ADU blends well into the neighborhood and minimizes its visual impact.

ADU Permit Process in San Diego

Building an ADU requires obtaining several permits, which can involve various steps:

1. Pre-Application: Before applying for permits, you may want to meet with a city planner to ensure your project meets zoning requirements.

2. Design Review: If your ADU requires any changes to the design or external appearance of your property, it will be subject to review by the city’s Planning Department.

3. Building Permits: Once your design is approved, you’ll need to submit for building permits. This involves providing detailed construction plans, including plumbing and electrical systems.

4. Inspection: After construction, the city will schedule inspections to ensure that your ADU meets safety and compliance standards.

Key Benefits of Building an ADU in San Diego

• Increased Property Value: Building an ADU can significantly increase the overall value of your property, making it an attractive investment.

• Rental Income: An ADU provides homeowners with the opportunity to earn passive income by renting out the space.

• Affordable Housing: ADUs are an affordable housing solution, especially in high-demand cities like San Diego.

• Family Flexibility: ADUs provide a flexible living arrangement for extended family, offering privacy and independence.