
Why Build an ADU in San Diego, California?
San Diego homeowners are capitalizing on the city's strong rental market and progressive ADU policies to create additional income and housing. With proximity to major employers like UCSD, Qualcomm, and military bases, ADUs in San Diego command premium rents while adding significant value to your property. The city's year-round perfect weather and streamlined permitting process make now the ideal time to build.
If you're not familiar with what an Accessory Dwelling Unit (ADU) is, it is a secondary housing unit on the same property as a primary residence, often used for rentals, guest accommodations, or extra family living space. Commonly called granny flats, backyard cottages, or in-law suites, ADUs offer homeowners flexible housing options, additional income potential, and increased property value. As cities like San Diego continue to seek solutions for housing shortages, ADUs have become a practical and popular choice.
Read our ADU guidesSan Diego ADU Market Insights
San Diego issued 2,761 ADU permits in 2023, more than doubling from 2020. Military personnel and biotech workers drive consistent rental demand. The city offers unique 'zero lot line' options for maximum space utilization. Proximity to Mexico creates additional rental opportunities for cross-border professionals. Average ADU adds $280,000 to property value.
- 30-40% average property value increase for San Diego homes with ADUs
- $1,500-$3,600 monthly rental income potential in San Diego's strong rental market
- $375-$600 per sq ft average construction costs in San Diego
Complete Guide to San Diego ADU Regulations
(2025 Updated)
San Diego has embraced ADU development with flexible regulations and incentives. The city allows ADUs in all residential zones and has eliminated many barriers that previously made construction difficult.
What You Can Build on Your San Diego Property
San Diego's ADU ordinance allows remarkable flexibility for homeowners:
1,200 sq ft for detached ADUs
50% of primary dwelling for attached ADUs (max 1,200 sq ft)
No minimum lot size requirements
0 feet allowed from side and rear property lines in some zones
4 feet standard for other areas
No setback for garage conversions within existing footprint
16 feet for detached ADUs
30 feet for attached ADUs (matching main house)
Additional height allowed for sloped lots
No parking required within Transit Priority Areas
One space per ADU required in other areas (can be tandem)
No replacement parking for garage conversions
Best Neighborhoods for ADUs in San Diego
San Diego's diverse neighborhoods offer unique opportunities for ADU development, from beachside communities to inland valleys with larger lots.
Clairemont
Central location
$1,800-2,400/month rentals
Large lots
Proximity to multiple employment centers
University City
Near UCSD and biotech corridor
High demand from researchers and students
$2,200-3,200/month rentals
Allied Gardens
Affordable development opportunities
Family-friendly with good schools
$1,600-2,200/month rentals
Pacific Beach
Premium coastal location
Strong vacation rental potential (30+ days)
$2,500-3,600/month rentals