San Diego at a Glance
1.4M
Population
—
Parcels
—
Median Lot
—
Median Assessed
Building Code Requirements
These are the key dimensions and limits that govern what you can build in San Diego. Every project — whether it's a new home, ADU, remodel, or addition — must comply with these requirements.
30'
Max Height
15'
Front Setback
5'
Side Setback
13'
Rear Setback
50%
Lot Coverage
2
Parking / Unit
Values shown are for standard single-family residential zones. Multi-family zones, commercial zones, and overlay districts have different requirements. View all San Diego zone tables →
What You Can Build in San Diego
California state law overrides many local zoning restrictions for housing development. Here's what's available to property owners in San Diego, regardless of what local ordinances say.
Accessory Dwelling Unit (ADU)
State LawBuild a second home on your lot — detached, attached, or converted from a garage. California law (AB 68 / AB 881) guarantees ADU rights for all residential properties. No minimum lot size. Cities must approve ministerially within 60 days.
Junior ADU (JADU)
State LawConvert space within your existing home into a separate rental unit — up to 500 sf. Can be built in addition to an ADU, giving you two income-producing units on one lot. Owner occupancy required for either the JADU or primary home.
SB 9 — Duplex + Lot Split
State LawSplit your lot in two and build a duplex on each half — up to four units total on what was a single-family lot. No public hearing, no discretionary review, no environmental review (CEQA exempt). Ministerial approval required.
SB 1211 — Streamlined ADU
State LawEffective January 2025: two-story ADUs up to 1,000 sf are pre-approved statewide. No local design review, no discretionary process. Cities must approve compliant plans within 30 days.
AB 1033 — ADU Condo Conversion
Opt-InIf your city has adopted a local ordinance, ADUs can be sold as separate condominiums — independent from the primary home. This unlocks a new path to homeownership and lets ADU builders recoup their investment through sale rather than rental income only.
Housing News in San Diego
Owners keep thousands of San Diego homes vacant despite high rents. They could soon be taxed
Apr 08 · LA Times California
California HOA triumphs over ADU law
Apr 06 · CalMatters Housing
California bill would require parent bloggers to delete content of minors on social media
Mar 26 · LA Times California
Contributor: Rent algorithms aren't the issue. California just needs more housing
Mar 26 · LA Times California
Sebastopol City Council approves ADU condo conversions, but that's just the beginning - sebastopoltimes.com
Jan 09 · sebastopoltimes.com
National Law Review: ‘San Diego ADU Incentive Rollback Sheds Light on California Housing Woes’ - OB Rag
Jul 18 · obrag.org
Frequently Asked Questions
Can I build an ADU in San Diego? +
Yes. California state law (AB 68/AB 881) allows at least one ADU on any residential lot in San Diego. ADUs up to 800 sf are approved ministerially within 60 days, regardless of local zoning.
What is SB 9 and does it apply in San Diego? +
SB 9 (California Housing Opportunity and More Efficiency Act) allows duplexes and lot splits on single-family lots statewide. In San Diego, this means you can potentially build up to 4 units on what was a single-family lot — no public hearing required.
What are the setback requirements in San Diego? +
Setback requirements in San Diego vary by zone. Use LotCheck to check your specific property's setback requirements against San Diego County's zoning code. For ADUs, California state law allows reduced setbacks of 4 feet for rear and side yards.
How much does an ADU cost to build in San Diego County? +
ADU construction in San Diego County typically ranges from $150,000 to $400,000 depending on size, finishes, and whether it's a conversion or new construction. Garage conversions tend to be the most affordable option.