Building an ADU in San Diego: A Step-by-Step Guide to Design, Permits, Costs, and ROI

2 min read RemodelSD San Diego, CA

Building an ADU in San Diego: A Step-by-Step Guide to Design, Permits, Costs, and ROI

By RemodelSD | January 09, 2026 | San Diego

ADU-ready outdoor living: smart site planning turns unused space into lifestyle value.

Accessory Dwelling Units (ADUs) are one of the smartest ways San Diego homeowners can add flexible space and long-term value. Whether you want a rental unit, a private suite for family, a home office that actually feels separate, or a guest house that makes entertaining easy, an ADU turns underused land into real lifestyle upgrades.

But ADUs are not “simple additions.” They are small homes with big requirements: planning, utilities, layout, permitting, budget control, and construction quality. The good news is that with the right plan and the right contractor, building an ADU can be one of the most rewarding projects you can do on your property.

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