How to Build the Perfect House and ADU for a Multigenerational Family in San Diego
More San Diego families are choosing to live together across generations—and doing it beautifully.
Whether you’re planning a remodel, a new build, or a backyard Accessory Dwelling Unit (ADU), the goal is the same: create a home that balances privacy, supports independence, and brings people together when it matters most. This guide focuses on San Diego’s unique housing market, local regulations, and lifestyle to help you design a multigenerational home that works for everyone.
Why multigenerational living is rising in San Diego
- Trends: High housing costs, limited inventory, and San Diego’s strong family culture are driving more households to live together under one roof—or one property line.
- Benefits: Shared childcare, elder care, and stronger family connections, with the option to rent out the ADU later for extra income.
- Property value: In San Diego’s competitive housing market, a well-designed ADU can significantly boost resale value and attract future buyers. Always verify short- and long-term rental rules with the City of San Diego.
San Diego-specific ADU and zoning considerations
San Diego has been proactive in encouraging ADUs as a solution to the housing shortage. Key things to know:
- Size limits: Most single-family lots can add at least one ADU and one JADU (Junior ADU). Detached ADUs can often be up to 1,200 sq. ft., but always confirm with the city’s planning department.
- Setbacks: In many cases, only 4-foot side and rear setbacks are required.
- Parking: Parking requirements are waived in many parts of San Diego if your property is within half a mile of public transit.
- Owner occupancy: Recent state laws have loosened owner-occupancy rules for ADUs, but check for updates if you’re considering renting.
- Permitting timeline: San Diego typically takes a few months to approve ADU permits, depending on complexity and workload. Start early to avoid delays.
Step-by-step path for San Diego families
- Define your family’s needs: Who lives in the main house now, and who will move into the ADU? Plan for 5–10 years down the road.
- Site planning: Consider San Diego’s terrain, coastal zones, and hillside ordinances. Document slopes, utilities, and access points.
- Budgeting: ADU costs in San Diego vary widely depending on size, finishes, and site work. Expect a significant investment and include a contingency for surprises.
- Assemble your team: Choose a local architect or design-build firm experienced with San Diego ADUs. Ask about recent permits they’ve handled in your neighborhood.
- Design for privacy and comfort: Pay special attention to noise, shared walls, and private outdoor areas.
- Permits and construction: Submit detailed drawings to speed up review and avoid costly change orders.
Outdoor living—San Diego style
- Shared spaces: Use your main yard for family BBQs, play areas, or gardening.
- Private ADU patios: Give the ADU a shaded terrace with drought-tolerant landscaping for privacy and water savings.
- Sustainable design: Consider permeable paving, rainwater capture, and native plants to align with San Diego’s sustainability goals.
Energy efficiency and sustainability
With San Diego’s climate and solar incentives, energy upgrades pay off quickly:
- Solar-ready roofs: Add conduit and panel capacity during construction.
- EV charging: Future-proof your property with a 240V outlet in the garage or driveway.
- Efficient HVAC: Heat pumps are ideal for San Diego’s mild climate.
Case study: A San Diego backyard cottage
The Garcias in Clairemont wanted to keep their college-aged son close while giving him independence. They built a detached ADU with a small kitchen, private patio, and separate entry. The ADU includes a mini-split heat pump, curbless shower, and extra insulation to buffer sound. The family wired for solar and an EV charger to prepare for the future. Now, their son enjoys independence while staying connected, and the unit is designed to eventually house aging parents—or be rented out for supplemental income.
Your next step
If you’re planning a multigenerational home in San Diego, start by sketching your site and writing down your must-haves. Meet with a local architect or design-build professional familiar with San Diego’s ADU regulations. Use the checklists above to guide your family conversations, and explore additional resources from the City of San Diego Development Services Department.
General Disclaimer: This article provides general information tailored to San Diego but is not legal, code, or engineering advice. Always verify zoning and building codes with the City of San Diego and consult licensed professionals (architect, engineer, contractor) before beginning any project.