Permitted ADUs Throughout San Diego County
California’s ADU reform laws have made San Diego one of the best places in the country to add a second unit. The City just approved 25 new ADU reforms. We build permitted, code-compliant ADUs from plans to final inspection.
Isaac visits every home personally. Free estimate, no sales pitch.
San Diego City Council recently approved 25 comprehensive ADU and JADU reforms that reduced fees, relaxed setbacks, and created clearer pathways for garage conversions and detached new builds. Under current rules, a single-family lot can accommodate up to three secondary units: one Junior ADU (JADU) within the existing structure, one converted ADU, and one fully detached ADU. ADUs under 750 sq ft are exempt from impact fees. State law requires permit decisions within 60 days. The rental income math now works clearly for most San Diego properties.
Detached ADUs can be up to 1,200 sq ft and 2 stories. JADUs max at 500 sq ft within the existing home. Properties in High or Very High Fire Hazard Severity Zones need a 4-foot side and rear setback for new detached ADUs. No impact fees for ADUs under 750 sq ft. We work with Sky Permits, our expediting partner, and know the specific requirements for both City of San Diego and unincorporated county parcels.
The questions most homeowners ask before booking an estimate.
Garage conversions (ADU or JADU) typically run $80,000–$130,000 depending on existing structure and finish level. Detached new-build ADUs range from $180,000–$350,000+ depending on size and site conditions. Per square foot, expect $200–$400 for conversions and $300–$500 for new construction. We give exact numbers after a site visit.
From first meeting to move-in, most ADU projects take 6–12 months. Design and permitting typically takes 2–4 months (state law requires permit decisions within 60 days). Construction on a garage conversion runs 3–4 months. A detached new-build runs 5–8 months. Using pre-approved county plans can shorten permitting significantly.
Most likely yes. California state law removed the minimum lot size requirement for ADUs — even small lots can qualify as long as they meet other criteria (residential zoning, setbacks, utility capacity). San Diego County’s ADU handbook and the City’s Development Services department are the authoritative sources for your specific parcel.
On a single-family lot in San Diego, you can now have up to three secondary units: one standard ADU (attached or detached, up to 1,200 sq ft), one Junior ADU (JADU, within the existing structure, up to 500 sq ft), and in some cases one additional conversion unit. The City of San Diego’s 2025 ADU reforms clarified these rules.
Yes — ADUs under 750 square feet are exempt from most impact fees under California’s SB 13, which can save $8,000–$15,000 on qualifying projects. All-electric ADUs may also qualify for additional utility rebates of $2,000–$3,000.
A one-bedroom ADU in San Diego typically rents for $2,500–$3,500 per month, or $30,000–$42,000 annually. A 2024 UCLA study found permitted ADUs in Southern California increased home values by $150,000–$300,000 depending on size. The rental income on a $200,000 garage conversion often covers the mortgage payment on the project within 5–7 years.
No — California removed the owner-occupancy requirement for ADUs in 2020 and it has not been reinstated. You can build and rent an ADU as an investment property without living on-site. San Diego’s 2025 ADU reforms preserved this.
Free in-home estimate. No sales team — you’ll meet Isaac, the owner, at the appointment.
Or call us: 619-866-2836
