Schedule ADU Consultation
(805) 864-5399 ext: 967
Schedule ADU Consultation (805) 864-5399 ext: 967

Thousand Oaks ADUs

Everything about building Accessory Dwelling Units in Thousand Oaks, CA

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The city government of Thousand Oaks has updated its local zoning codes to comply with the State ADU mandate.
The California Building Code (CBC) 2019 is adopted.

Last Updated 10/13/20


City Hint: The city permitted a total of 17 ADU projects in the past year of 2019, which is below the average compared to other cities in California.

Number of ADUs allowed:

1 junior and 1 attached or detached ADU are allowed on single-family lots. Multifamily lots may have 2 detached ADUs and attached ADUs equal to 25% of the multi-family units.

Types of ADUs allowed:

Detached ADU, Attached ADU, Junior ADU are allowed. ADUs may be new construction or converted from existing space. JADUs must be converted from existing space.

Lot size:

Single family and multi-family residential properties will not be subject to the minimum lot size of the underlying zoning district or by ordinance for ADU projects. ~ Updated: State Law AB-68

ADU size:

o Junior ADU: 500 square feet
o Attached ADU: 50% of primary residence area
o Detached ADU: 850 square feet for a studio or 1- bedroom unit and 1,000 square feet for a 2- bedroom or larger unit


Junior and attached ADUs are subject to the same setbacks as the primary residence. Side and rear setbacks for detached ADUs are 4 ft.


One parking space is required for attached and detached ADUs with 1 or more bedrooms. The parking may be uncovered and may be tandem in a driveway. No parking is required for studio units or junior ADUs. ADUs are exempt from parking requirements in certain situations Parking is not required for an ADU meeting any of the following criteria:
o Located within ½ mile of public transit
o Located in an architecturally and historically significant district
o Located within one block of car share vehicle
o Located within an existing structure that has been expanded by no more than 150 square feet

Fire Safety:

Fire sprinklers are required if the primary residence has fire sprinklers and may be required otherwise per the Fire Department under certain conditions

Shape, materials and style:

i) Materials and colors of exterior walls, roof, eaves, windows, and doors of an ADU must match those of the primary dwelling.
ii) Roof slope of ADU must match the dominant roof slope of the primary dwelling.
iii) ADU must have an independent exterior entrance separate from the primary dwelling.


Junior and attached ADUs have the same maximum height as the primary dwelling unit. Detached ADUs are limited to a maximum height of 16 feet

Design review:

One of the residential units on the lot shall be occupied by the property owner. Attached or detached accessory dwelling units shall not be located within one hundred (100) feet of any publicly or privately-owned natural open space. Attached or detached accessory dwelling units shall be reviewed ministerially. The accessory dwelling unit must contain at minimum an efficiency kitchen.
The accessory dwelling unit shall not be located in the front yard area between the primary residence and the street.

Number of Bedrooms:

Attached or detached accessory dwelling units shall be reviewed ministerially.


Owner-occupancy will not be required for new Accessory Dwelling Unit (ADU)s (conversion and new construction) built between 2020 and 2025. ~ SB13

Utility connections:

Local health officer approval where a private sewage disposal system is being used, if required. (State requirements)

Allowed Zones:

*** Beginning in 2020, according to state law, all residential zoning districts, including single-family and multi-family, are allowed to build Accessory Dwelling Units. ***

Residential Building Code:

The California Building Code (CBC) 2019 is adopted.

Call/Text ADU Operator (805) 864-5399
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ADU Design Library

Browse hundreds of models to find the right fit for your property.

ADU Model 400 sqft

W 20 ft L 20 ft

ADU Model 927 sqft

W 38 ft L 27 ft

ADU Model 500 sqft

W 25 ft L 20 ft

Customer Reviews

"Housable has been a great resource regarding my ADU project. I purchased both the Property and Design Reports. In both cases, they delivered as promised and on time."

Ed in Corona, CA

"The property report was great! Made me feel like my project is feasible."

Alexandria in Santa Ana, CA

"My experience with Housable was exceptional. The team was extremely helpful and responsive. I am very satisfied and happy to have used these services. As a home owner I do not know the construction lingo or process but the Housable team very kind and helpful and patient with me. My expectations were exceeded. Thank you for everything."

Monica H. in Oakland, CA

Complete 5-Step Process

Browse hundreds of permit-ready ADU designs and order one to customize to your needs.
Connect with local contractors to get site visits and cost estimates for your project.
Mark up changes to your plans and provide critical info needed to permit your project.
Finalize your project blueprints to submit for building permits.
Select your contractor and build your project.

What our customers say:

Customer Reviews

"My permits were APPROVED, thank you for all your hard work. I am in the process of meeting with contractors. "

Mary S. in San Jose, CA

"I just wanted to let you know that the permit process has been completed and we are currently in the construction phase. The work you guys did was great and I will definitely be using this service again in the future. I will keep you guys updated on anything important. Thanks!"

Patrick L. in Orange County, CA

Detached ADU - Completed in 2020
1,003 sq. ft., 3 bed, 2 bath

Estimate Your ADU Potential
Costs / ROI



* upon completion of ADU


* based on local average price per sqft


* estimated by location


* 30 years / 5% interest rate / 20% down payment


Size: 500 sqft


Appreciation Estimate = (Base Value: $) / (Home's Living Space: sqft) * (ADU's Living Space: sqft)

Rental Estimate = (Rent Per Sqft: $3.95) * (ADU's Living Space: sqft)

Check your property's zoning, browse designs & get contractor estimates for your ADU project:

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Housable is providing information about specific properties that is furnished to users as a good-faith estimate of the development potential of a property. You should not in any way base your development, investments, or other financial decisions on this information. We strongly advise you to consult with an industry professional, such as a lender, realtor, contractor, or architect, who is sufficiently licensed and insured in their field, and who can work with you individually to confirm all requirements before moving forward with any real estate development or investment.