Can I Build Second Story Addition in San Diego, CA? (2026)
Find out if you can build a second story addition in San Diego, CA. Rules, permit requirements, costs, and next steps.
Adding a second story in San Diego, CA is possible in most zones, subject to height limits and structural permit requirements.
A second story addition is one of the most complex home improvement projects in San Diego, CA. It requires a full building permit, structural engineering review, and must comply with the height limits for your zoning district. Unlike a ground-floor addition, a second story changes the roofline and structural load path of your entire home, triggering stricter engineering requirements. In San Diego, zone height limits range from 30 feet in RS-1-4 zones — verify your zone before planning.
Second Story Addition Rules in San Diego
Second Story Addition Rules in San Diego: Building permit required: Yes — all second story additions require a permit. Permit thresholds: All structural additions require permit. Example height limit (RS-1-4): 30 feet, max 2 stories. Structural engineering drawings required. Setbacks apply to the full structure height. SD DSD building permit required. Community plan design guidelines may apply. Coastal Zone additions require Coastal Development Permit in addition to building permit. FAR and lot coverage limits apply.
Costs & Fees
Second story addition permit fees in San Diego: Valuation-based — typically $2,000–$12,000+. Note: structural engineering fees ($2,000–$10,000+) are separate from permit fees.
Timeline
Plan check: 6-12 weeks plan check. Construction typically 3-6 months for a full second story.
Next Steps
Next steps for adding a second story in San Diego: 1. Hire a structural engineer to assess your existing foundation and framing capacity. 2. Confirm your zone height limit and verify the addition meets all setback requirements. 3. Submit full structural plans and permit application to the San Diego Development Services Department (DSD). 4. Inspections required at foundation reinforcement, framing, shear panels, and final.
San Diego Development Services Department (DSD)
Phone: (619) 446-5000
Website: https://www.sandiego.gov/development-services
Online Permits: https://www.sandiego.gov/development-services/opendsd
Frequently Asked Questions
Can I build an ADU in my backyard in San Diego?
Yes. California state law requires San Diego to permit ADUs by-right on all residential lots. You can build a detached ADU up to 1,200 sqft, plus a Junior ADU (JADU) up to 500 sqft within your existing home. No owner-occupancy requirement applies. San Diego also offers a Standard ADU Plan Program to speed up permit approval. Permits are processed within 60 days.
What are San Diego's Airbnb (short-term rental) rules?
San Diego requires a Short-Term Residential Occupancy (STRO) license ($150/year) for all rentals under one month. There are four license tiers: Home-Sharing (hosted), Whole-Home Primary Residence, Mission Beach properties, and Whole-Home Non-Primary Residence (limited citywide via lottery). The 10.5% Transient Occupancy Tax applies to all short-term rentals. Operating without a license carries fines of $1,000 per day.
How does San Diego's zoning system work?
San Diego uses the Land Development Code (LDC) with community plan areas governing local land use. Residential zones use a numeric system — RS (Residential Single Unit) or RM (Residential Multiple Unit) followed by numbers indicating density (e.g., RS-1-4 = single-unit residential, 4,000 sqft minimum lot). Each of San Diego's 107+ communities has its own community plan that implements the General Plan for local conditions.
Do I need a permit to run a business from my home in San Diego?
Yes. A Home Occupation Permit ($175) is required for any business operated from a residence. Restrictions: no clients on-site, no non-resident employees, no exterior signs, maximum 25% of floor area used for business. San Diego's LDC Section 113.0295 governs home occupations.
What are the setback requirements for a single-family home in San Diego?
Setbacks in San Diego vary by zone designation. In the most common RS-1-4 (single-family residential) zone: front yard 15 ft, side yards 4 ft, rear yard 15 ft. Larger lot zones (RS-1-7, RS-1-14) have proportionally larger setbacks. Canyon-adjacent properties often have additional open space easements limiting building closer to canyon edges.
Are solar panels required on new homes in San Diego?
Yes. California's Title 24 Energy Code requires solar PV on all new low-rise residential construction. San Diego receives 266+ sunny days per year — one of the best solar markets in the US. SDG&E net metering is available. Properties in San Diego's Coastal Zone may need additional Coastal Commission review for rooftop modifications, but solar cannot be denied for code-compliant installations.
What is San Diego's Coastal Zone and how does it affect my property?
San Diego's Coastal Zone encompasses roughly the westernmost 3-4 miles of the city, covering neighborhoods like Ocean Beach, Mission Beach, Pacific Beach, La Jolla, and others. Properties in the Coastal Zone require a Coastal Development Permit (CDP) from the California Coastal Commission for new construction, additions over 10% of existing floor area, and some changes to primary structures. This applies in addition to regular city building permits and can add 2-6 months to project timelines.
Source: San Diego Development Services Department (DSD) — Building Regulations. Last verified April 5, 2026. View source