A guide for building backyard homes in

Oakland, California

Accessory Dwelling Units (ADUs) in Oakland are allowed under state law, and a single-family home may construct at least one ADU. Owner-occupied single-family properties may construct one ADU and one Junior ADU, while multi-family properties with four or more existing residential units may construct one ADU. ADUs may be either new construction or converted from existing space, and can be detached, attached, or junior.

Yes, a permit is required to construct an Accessory Dwelling Unit (ADU) in Oakland. The permit process will vary depending on the type of ADU you are constructing and the regulations in place in your specific location. At Type Five, we handle the entire permit process for you.

The maximum amount of time the city of Oakland has to review your permit application is within 60 days of submission. It is possible to get your permit approved within 30-90 days of submission so long as your designs were drawn with the local code in mind.

Under state law, a single-family home in Oakland may construct at least one Accessory Dwelling Unit (ADU). Owner-occupied single-family properties may also construct one ADU and one Junior ADU. Multi-family properties with four or more existing residential units may construct one ADU. However, the exact number of ADUs allowed on a property may vary depending on the specific regulations in place in your area. You should consult with the city of Oakland and your local zoning board to determine the specific number of ADUs allowed on your property.

There is no minimum lot size requirement for an ADU in Oakland. California state law also mentions that lot coverage requirements can’t preclude the creation of a statewide exemption ADU. A statewide exemption ADU is 800 square feet, with a height limitation of 16 feet and and 4 feet rear and side yard setbacks.

In Oakland, the size of an Accessory Dwelling Unit (ADU) is determined by its category. Category 1 ADUs are limited to a floor area of either 50% of the existing primary residential facility or 800 square feet, whichever is greater. Category 2 ADUs have different size limitations depending on whether they are attached or detached. Attached Category 2 ADUs are limited to 50% of the floor area of the primary residential facility, or 850 square feet for one-bedroom units and 1,000 square feet for units with more than one bedroom, whichever is greater. Detached Category 2 ADUs are limited to a floor area of 1,200 square feet. Type Five's system can adapt to fit within these requirements, but most importantly to the available are you have to build.

It is possible to construct a two-story Accessory Dwelling Unit (ADU) in Oakland, but it may be subject to certain limitations. The height of an ADU in Oakland is determined by its category and its location on the property. Category 1 ADUs do not have any height restrictions, while Category 2 ADUs must be subordinate in height to the primary dwelling and must comply with the height limits of the underlying zoning district.

Additionally, any attached or detached ADUs located outside required setbacks must be limited to the height of the primary dwelling, except in certain specific zoning districts. It is recommended that you consult with the city of Oakland and your local zoning board to determine the specific height requirements for your proposed ADU.

Type Five offers a two-story model that fits Oakland's requirements.

There is no limit to the number of bedrooms an ADU can have in the city of Oakland according to California state law. The California HCD ADU handbook states that a limit on the number of bedrooms could be construed as a discriminatory practice towards protected classes, such as familial status, and would be considered a constraint on the development of ADUs.

The setbacks for building an Accessory Dwelling Unit (ADU) in Oakland will depend on the type and location of the ADU. Under state law, newly constructed detached ADUs can be as close as 4 feet from the rear and side property lines. Attached ADUs and conversions from existing space that are expanded must comply with the setbacks of the underlying zone.

In Oakland, the requirements for utilities in an Accessory Dwelling Unit (ADU) are determined by the category of the ADU. Category 1 ADUs do not require a new or separate utility connection. Category 2 ADUs may require a new or separate utility connection, but the connection fee or capacity charge must be proportionate to the burden of the ADU on the water or sewer system.

In most cases, fire sprinklers are not required in an Accessory Dwelling Unit (ADU) in Oakland. An ADU is only required to provide fire sprinklers if sprinklers are required for the primary dwelling unit. However, the ADU must still meet other fire safety requirements, such as minimum fire flow and water pressure on the adjoining streets.

You are required to install solar panels on your ADU in Oakland if your ADU is a newly constructed, non-manufactured, detached ADU.

You should be able to rent an ADU in Oakland for $1,975 which is the average monthly rent for a one bedroom apartment so long as the rental term is longer than 30 days. There is no owner-occupancy requirement for ADUs built before December 31st, 2024.

You cannot use an ADU as an AirBnB in Oakland unless you are renting it out for a period longer than 30 days. California law states that ADUs created under subdivision (e) of Gov. Code, § 65852.2 cannot be rented for a period less than 30 days. This means you cannot use your ADU as a short-term rental in Oakland.

Your local homeowners association (HOA) cannot prohibit the construction of an ADU or JADU in Oakland. Assembly Bill 670 (2019) and AB 3182 (2020) amended Section 4751, 4740, and 4741 of the Civil Code to preclude common interest developments from prohibiting or unreasonably restricting the construction or use, including the renting or leasing of, an ADU on a lot zoned for single-family residential use.

Covenants, conditions and restrictions (CC&Rs) that either effectively prohibit or unreasonably restrict the construction or use of an ADU or JADU on such lots are void and unenforceable or may be liable for actual damages and payment of a civil penalty.

The city of Oakland will assess the value of your newly added ADU, typically by using the cost-bases method of appraisal, and multiply it by the property tax rate of 1%. So if your ADU in Oakland costs $217,053 to build, you can expect your annual property taxes to increase by $2,170.53 per year. Adding an ADU to your property will not trigger a reassessment of the value of your primary residence.

Adding an ADU to your property in Oakland typically adds value to your property, however, the exact amount depends on the appraisal method that your appraiser chooses to use. If an appraiser uses the cost-basis method & the cost of your ADU is $217,053, then you can expect your home value to appreciate by $217,053.

Another method that an appraiser can use is the sales comparison approach, where the value of the ADU addition is determined by recently sold properties in Oakland that included ADUs. However, this approach depends on the number of recently sold properties and there sometimes isn’t enough information to use this approach with ADUs. A back-of-the-envelope way to estimate the value yourself would be to multiply the existing price per square foot of your property by the square footage added by the ADU and compare it to the cost of your ADU. The appreciation is likely in between those two numbers.

The average cost to build an ADU in Oakland is $217,053. Keep in mind there are a ton of factors to consider when estimating the cost of a project, many of which are unique to your property and sometimes require special surveys to identify. Examples of these factors include whether or not your property is flat or sloped and whether or not you need to upgrade your utilities.

It’s also important to note that converting an existing structure or converting your garage into an ADU isn’t necessarily cheaper than building a brand new detached ADU. You can get an in-depth overview about what goes into the costs of building an ADU in your city by starting to customize your ADU using Type Five's design tool.