Rancho Santa Fe ADU for Mother-in-Law with Detached Garage
Rancho La Cima Drive, Rancho Santa Fe, CA 92091
Homeowner Story: Bring aging family closer
Other Features: Garage
Special Circumstance: HOA
Custom Rancho La Cima Estates HOA ADU
This Rancho Santa Fe ADU presents an ideal living arrangement for a mother-in-law seeking independence and a peaceful atmosphere. Spanning 1,200 square feet, this luxurious ADU offers two bedrooms and two bathrooms, ensuring ample space for her to call home. Being located within the Rancho La Cima Estates HOA, we ensured the exterior of the ADU matches the primary home and meets all of their architectural standards. Learn more about building an ADU in an HOA.
Additionally, the ADU features a detached two-car garage, providing parking and convenient storage options. Read more about building an ADU with a garage.
Floor Plan:
2BR/2BA 31×48 L-Shape
Community:
The County of San Diego Accessory Dwelling Unit Guide
The County of San Diego oversees ADU development throughout the region’s unincorporated communities, including areas such as Rancho Santa Fe, Valley Center, Bonsall, Fallbrook, Lakeside, Spring Valley, and many others. You may also think your property is in a certain jurisdiction because your address includes a city, such as Escondido, but you actually fall outside of city limits and are within the county jurisdiction. Understanding which jurisdiction applies is one of the first steps in determining what can be built.
The County allows a variety of ADU configurations, including two-story ADUs and guest quarters in addition to an ADU. In 2026, the County also became one of the first jurisdictions in San Diego County to adopt AB1033, allowing qualifying ADUs to be sold separately from the primary residence. As of June 2026, only the County of San Diego and the City of San Diego have adopted AB1033.
Unlike many jurisdictions, the County still requires in-person permit submissions, which can add some time and coordination during the permitting process. Depending on the location of the property, other agencies such as local fire districts may also require review and approval before permits can be issued.
San Diego County ADU Permitting
Most ADU permits within the County of San Diego are approved within approximately 3 to 5 months after submission, although timelines vary depending on project complexity and agency review requirements. Compared to some cities within San Diego County, permit fees are generally moderate. ADU permit costs often range from approximately $15-$18 per square foot, depending on the size and scope of the project.
The County requires in-person permit submissions and, depending on the property’s location, additional review from agencies such as local fire districts. Early planning can help identify these requirements and create a more predictable permitting process.
Unlike many coastal cities in the region, only a small portion of the County’s jurisdiction falls within the Coastal Zone. Most County ADU projects therefore do not require Coastal Zone review.
