City ADU planning guide

Santa Clara ADU regulations and next steps

Start with the most important planning decisions, then review the detailed city rules below before choosing a detached ADU plan or requesting a property-specific feasibility review.

Santa Clara ADU rules overview

Detailed local requirements vary by property. Use this section as a starting point for setbacks, parking, height, utilities, and approval considerations.

Lot fit

Setbacks and buildable area

Start with rear and side setbacks, lot coverage, access, and where a detached ADU can realistically sit on the property.

Design limits

Size, height, and unit type

Check whether the property is better suited for a detached ADU, attached ADU, garage conversion, or junior ADU.

Approvals

Parking, utilities, and permits

Confirm parking exemptions, utility connection requirements, impact fees, and city review steps before finalizing plans.

In Santa Clara, California, Accessory Dwelling Units (ADUs), commonly referred to as "granny flats " or "in-law units," are subject to both local and state regulations. While the state of California has passed numerous laws aimed at simplifying the process for building ADUs, cities like Santa Clara still have their own specific requirements. Here's an overview of ADU regulations in Santa Clara as of 2024:

Santa Clara allows the construction of two types of ADUs:

  • Detached ADUs Separate structures on the same lot as the primary residence.
  • Attached ADUs Units that are part of or attached to the primary residence (e.g., converting a garage or expanding an existing structure).

Additionally, Junior ADUs (JADUs) are smaller units, typically under 500 sq. ft., that can be created within the existing home, often by converting a bedroom.

Zoning and Location:

  • Zoning Requirements ADUs are generally permitted in residential zones, but there may be certain restrictions based on specific zoning designations.
  • Lot Size Typically, a minimum lot size of 3,000 sq. ft. is required to build an ADU, although this can vary.

Size Limitations:

  • Detached ADUs
    • Minimum size: 150 sq. ft.
    • Maximum size: 1,200 sq. ft. (may vary depending on the type of ADU and other factors like setbacks and height restrictions).
  • Attached ADUs The size of an attached ADU depends on the size of the existing house. Generally, an attached ADU cannot exceed 50% of the primary dwelling’s size, with a maximum of 1,200 sq. ft.
  • Junior ADUs (JADUs)
    • Must be no larger than 500 sq. ft.

Setback Requirements:

  • Detached ADUs must be set back from the property lines
    • Rear yard: Typically 4 feet, but may vary depending on the specifics of the property.
    • Side yard: Generally, 4 feet.
    • Attached ADUs must meet the same setback requirements as the primary structure.

Height Limitations:

  • Detached ADUs are typically limited to one story, with a height restriction of 16 feet (although this may be increased depending on the context, like if the ADU is located in a certain type of zoning district).
  • Attached ADUs must adhere to the height of the primary dwelling.

Parking Requirements:

  • Detached ADUs may require one additional parking space, though in many cases, this requirement can be waived if the property is within close proximity to transit options or if the ADU is located within certain districts.
  • unior ADUs (JADUs) do not require additional parking, as long as they are within the existing structure.

Impact Fees:

  • Santa Clara may charge impact fees for ADUs, depending on the size of the unit and its proposed use. The city has been working to lower these fees, especially for smaller units, to encourage ADU development.
  • State law also limits the fees that cities can charge for ADUs, particularly for units under 750 sq. ft.

ADU Permitting Process:

  • Building Permit You will need to obtain a building permit to construct an ADU. In most cases, you can submit an application online via the City of Santa Clara’s planning portal or through the Planning Division.
  • Streamlined Process California state law requires that cities provide a streamlined approval process for ADUs, with decisions typically made within 60 days of application submission (with some exceptions).

Design Review:

  • In many cases, ADUs in Santa Clara do not require a design review process, but they must still comply with design standards, such as
    • Compatibility with the existing home and surrounding neighborhood.
    • Use of appropriate materials and finishes.
  • If the ADU is part of a historic district or a specially designated area, additional review may be required.

Utilities:

  • ADUs must be connected to utilities such as water, sewer, and electricity. In some cases, the city may require separate utility meters for the ADU, especially if it’s a larger, detached unit.

Short-Term Rentals:

  • In Santa Clara, as in many other parts of California, ADUs cannot be used for short-term rentals (e.g., Airbnb) unless the primary residence is also used for short-term rentals. ADUs must be occupied by long-term tenants.

ADU Conversion Rules:

  • Homeowners may also convert existing structures like garages, basements, or attics into ADUs. However, the conversion must meet certain requirements regarding safety, building code compliance, and utility access.

State Legislation:

  • It's important to note that state laws supersede local ordinances when it comes to certain aspects of ADU development. California’s recent laws (such as SB 13, AB 68, and AB 881) aim to make it easier to build ADUs by:
    • Reducing or eliminating certain local regulations like parking requirements or minimum lot sizes.
    • Prohibiting certain fees for ADUs under a certain size.

Key Resources:

Show More

ADU planning resources

Explore ADU service areas and planning next steps

Compare nearby ADU city pages, review plan options, and move from early research to a property-specific ADU conversation.

Start here

Compare detached ADU plans

Review sizes, layouts, and configurable ADU options before your feasibility call.

Browse ADU plans
Budget

Understand ADU financing

See common funding paths and how homeowners think about ADU return potential.

Explore ADU financing
Process

Know what happens next

Walk through feasibility, design, permitting, and construction with Metricon Homes.

See how ADUs work

More ADU service areas

Bay Area ADUsCosta Mesa ADUsLos Angeles ADUsOakland ADUsSacramento ADUsSan Diego ADUsSan Francisco ADUsSan Jose ADUs

Build Your ADU with Metricon Homes

Metricon Homes helps you plan and build a fully custom Accessory Dwelling Unit tailored to your property, lot, and local regulations. From feasibility and design through permitting and construction, our team manages the entire process so you can add flexible living space, host family, or generate rental income with confidence.

Contact us today for a free property assessment and start planning your ADU.

CALL (833) 400-2497

Explore our ADU plans

Learn More(833) 400-2497