ADU Builder in Casa Conejo, Newbury Park

Casa Conejo ADUs Are Permitted by Ventura County

Construction of Casa Conejo began in 1960, making it the first planned community in what became Newbury Park. When the surrounding land was annexed into Thousand Oaks, Casa Conejo stayed outside city limits. Today it is home to about 3,267 people (2020 census) and is governed by Ventura County through its Thousand Oaks Area Plan.

For an ADU, that changes the whole permit path. The City of Thousand Oaks ADU ordinance does not apply. Instead, the county's Non-Coastal Zoning Ordinance governs, as updated by the Board of Supervisors on June 4, 2024 and in effect since July 3, 2024. HCD reviewed that update and confirmed in January 2025 that it complies with state law, so county standards here are more settled than the city's newer ordinance. Applications go to the Ventura County Resource Management Agency, starting with the Planning Division and moving to Building and Safety for plan check.

Early-1960s Ranch Homes and What They Mean for an ADU

Casa Conejo houses are mostly single-story ranch homes on flat, regular lots with a two-car garage. That is close to an ideal starting point for an ADU, but six decades of age show up once the walls are open. Original electrical services are often small for modern loads. Sewer laterals from the era are frequently clay pipe, and roots find the joints. Garage slabs may lack a vapor barrier, and older framing may not be bolted to its foundation.

None of that rules out a project. It means the investigation phase matters. We camera the sewer lateral, check the electrical panel and service, look at the garage foundation and framing, and note any past additions or conversions that may not have been permitted. With that information, the design and budget reflect the real house rather than a hopeful assumption.

• Sewer lateral video inspection to the street
• Main panel and SCE service capacity check
• Garage slab, footing and anchor bolt review
• Search for past unpermitted additions

ADU Types That Suit Casa Conejo Lots

The garage conversion is the natural first choice here. A two-car garage on a ranch house becomes a studio or small one-bedroom, keeps the backyard open and avoids new foundations. Nobody can make you rebuild the parking, and converted space is exempt from unit-size limits.

Flat backyards also make detached cottages practical. State law allows by right a new freestanding unit as large as 800 sq ft, sited as close as 4 feet to side and rear lines, and a single-story layout on a slab keeps costs predictable. Owners who want to stay flexible sometimes start with a junior ADU inside the house, leaving the garage and yard for a later phase. All three can coexist on one single-family lot under state law.

Working With the County From a Thousand Oaks Address

Casa Conejo residents use Thousand Oaks and Newbury Park addresses, shop in the city and send children to local schools, so the county jurisdiction surprises many owners. We confirm it from the parcel record and prepare the submittal to the county's ADU checklist. State review deadlines still apply: 15 business days for a completeness determination and 60 days to act on a complete application where a house already exists.

Utility providers may differ from those on neighboring city streets as well. We confirm which water purveyor and sewer provider serve the parcel before designing the connections, and SCE handles electrical service as it does throughout the area.