California SB 1117: Save $3,500-$15,000 on Pacific Beach ADUs Starting January 1, 2027

What SB 1117 Changes: How the 750 Sq Ft Exemption Works

California's new ADU impact fee reform fundamentally changes how local governments calculate development impact fees for accessory dwelling units. Understanding the difference between old and new rules is essential for maximizing savings on your Pacific Beach ADU project.

OLD RULE (Pre-January 1, 2027): Many California cities, including San Diego, charged impact fees on the entire floor area of ADUs once they exceeded the 750 sq ft threshold. Under the proportional calculation method, a 1,000 sq ft ADU on a lot with a 2,000 sq ft primary dwelling would pay 50% of the full impact fee—meaning if the primary dwelling owed $20,000 in impact fees, the ADU would owe $10,000.

NEW RULE (SB 1117, Effective January 1, 2027): The first 750 sq ft of EACH of up to TWO ADUs is now completely exempt from ALL impact fee calculations. Instead of charging fees based on the entire ADU's size, local governments can only charge proportionally for the square footage above 750 square feet. Using the same example, a 1,000 sq ft ADU now pays fees on only 250 sq ft (the excess above the 750 sq ft exemption), reducing the impact fee from $10,000 to just $2,500—a savings of $7,500.

How the Calculation Works: For a Pacific Beach ADU of any size, you subtract 750 square feet from the total square footage to determine the taxable area. A 600 sq ft ADU has zero taxable square footage (fully exempt). An 800 sq ft ADU has only 50 sq ft subject to fees. A 1,200 sq ft ADU pays fees on 450 sq ft instead of the full 1,200 sq ft.

All Impact Fee Categories Covered: SB 1117's exemption applies to ALL development impact fee categories mandated by the Mitigation Fee Act, including:

• School district impact fees ($5.38/sq ft in San Diego as of May 2026)
• Parks and recreation facilities fees
• Fire-rescue facilities fees
• Library facilities fees
• Mobility and transportation fees

The exemption does NOT apply to building permit fees, plan check fees, or utility connection charges—those remain separate costs.

Dual ADU Benefit: One of SB 1117's most powerful provisions applies to properties building two ADUs. Each unit gets its own 750 sq ft exemption. If you build two 800 sq ft ADUs on your Pacific Beach lot (assuming zoning permits dual ADUs), each unit exempts 750 sq ft, meaning you pay impact fees on only 50 sq ft per unit—100 sq ft total instead of 1,600 sq ft. This dramatically improves the economics of dual ADU projects.

Statewide Applicability: Unlike local ordinances that vary by jurisdiction, SB 1117 is a statewide California law sponsored by Senator Sabrina Cervantes (D-Riverside) and signed by Governor Newsom on September 29, 2026. The legislation explicitly declares ADU fee reform "a matter of statewide concern," meaning it overrides local ordinances and applies uniformly to all California cities and counties—including charter cities that typically retain local control. Pacific Beach, La Jolla, Mission Beach, and Bird Rock residents are guaranteed these savings regardless of local politics or City Council decisions. Learn more about California's comprehensive ADU law reforms.

Pacific Beach ADU Savings Calculator: Exact Fee Reductions by Size

Translating SB 1117's exemption into actual dollar savings requires understanding San Diego's current impact fee structure. Here's what Pacific Beach homeowners can expect to save on ADUs of different sizes starting January 1, 2027.

San Diego Impact Fee Baseline (2026 Rates):

• School impact fees: $5.38 per square foot (San Diego Unified School District, effective May 10, 2026)
• Parks, Fire, Library, Mobility fees: Variable by location, but typically range $8-$15 per square foot combined
• Total estimated impact fees: $13-$20 per square foot for residential construction in most San Diego neighborhoods

ADU Size	Exempt Sq Ft	Taxable Sq Ft	Total Savings
600 sq ft	600	0	$3,900-$6,000
800 sq ft	750	50	$4,550-$7,000
1,000 sq ft	750	250	$3,250-$5,000
1,200 sq ft	750	450	$1,950-$3,000
Two 800 sq ft ADUs	1,500	100	$9,100-$14,000

600 Sq Ft ADU:

• Exempt square footage: 600 sq ft (fully exempt under 750 sq ft threshold)
• Taxable square footage: 0 sq ft
• School fees under SB 1117: $0
• Total impact fees under SB 1117: $0
• Pre-SB 1117 impact fees (proportional): ~$3,900-$6,000
• TOTAL SAVINGS: $3,900-$6,000

800 Sq Ft ADU:

• Exempt square footage: 750 sq ft
• Taxable square footage: 50 sq ft
• School fees under SB 1117: $269 ($5.38 × 50)
• Total impact fees under SB 1117: ~$650-$1,000
• Pre-SB 1117 impact fees (proportional): ~$5,200-$8,000
• TOTAL SAVINGS: $4,550-$7,000

1,000 Sq Ft ADU (Most Common Size):

• Exempt square footage: 750 sq ft
• Taxable square footage: 250 sq ft
• School fees under SB 1117: $1,345 ($5.38 × 250)
• Total impact fees under SB 1117: ~$3,250-$5,000
• Pre-SB 1117 impact fees (proportional): ~$6,500-$10,000
• TOTAL SAVINGS: $3,250-$5,000

1,200 Sq Ft ADU:

• Exempt square footage: 750 sq ft
• Taxable square footage: 450 sq ft
• School fees under SB 1117: $2,421 ($5.38 × 450)
• Total impact fees under SB 1117: ~$5,850-$9,000
• Pre-SB 1117 impact fees (proportional): ~$7,800-$12,000
• TOTAL SAVINGS: $1,950-$3,000

Dual ADU Scenario: Two 800 Sq Ft ADUs (1,600 Sq Ft Total):

• Exempt square footage: 1,500 sq ft (750 sq ft per unit × 2 units)
• Taxable square footage: 100 sq ft total (50 sq ft per unit × 2 units)
• School fees under SB 1117: $538 ($5.38 × 100)
• Total impact fees under SB 1117: ~$1,300-$2,000
• Pre-SB 1117 impact fees (proportional): ~$10,400-$16,000
• TOTAL SAVINGS: $9,100-$14,000

Important Notes on Calculations:

1. Savings assume proportional impact fee methodology was used pre-SB 1117. Some jurisdictions may have had different fee structures.
2. School fees are fixed at $5.38/sq ft statewide (May 2026 rate). Other impact fees vary by specific location within San Diego.
3. These calculations do NOT include building permit fees or plan check fees, which are separate from development impact fees.
4. For precise calculations on your specific property, request the current Development Impact Fee schedule from San Diego Development Services or consult with our experienced ADU construction team.

November-December 2026 Strategic Decision: Rush Permit or Wait for SB 1117?

Pacific Beach homeowners planning ADUs face a critical two-month decision window. Should you rush to submit your permit application by December 31, 2026 under current rules, or wait until January 2027 to capture SB 1117 savings? The answer depends on your design readiness, construction timeline priorities, and financial goals.

SCENARIO 1: Rush Permit Submission (Submit by December 31, 2026)

Advantages:

• Potentially faster approval if San Diego Development Services processes pre-deadline applications aggressively
• Avoid potential January 2027 submission queue and backlog
• Lock in current fee schedules if other fees (utilities, permits) might increase in 2027
• Start construction sooner if crews are already booked for Q1 2027

Disadvantages:

• Pay $3,250-$7,000 more in impact fees on typical 800-1,200 sq ft ADUs (or miss out on dual ADU savings of $9,100-$14,000)
• Design and engineering plans must be 100% complete and permit-ready by mid-December 2026
• Risk rushing critical design decisions to meet deadline
• Limited time for contractor selection and contract negotiation
• Coastal Development Permit coordination may be compressed under AB 462's 60-day timeline

SCENARIO 2: Wait for SB 1117 (Submit January 2027 or Later)

Advantages:

• Save $3,250-$7,000 on single ADUs or $9,100-$14,000 on dual ADUs
• More time for thoughtful design optimization and maximizing the 750 sq ft exemption
• Better contractor selection with time to vet multiple bids
• Benefit from fee exemption certainty—no risk of calculation errors or disputes
• Ability to coordinate with AB 462 coastal permitting without timeline pressure

Disadvantages:

• Potential January 2027 application backlog if many homeowners wait for SB 1117
• Lose approximately 2 months of construction timeline
• Other fees (utilities, building permits) could potentially increase in 2027 (though impact fee savings likely outweigh this risk)
• Construction crews may have less availability if Q1-Q2 2027 books up

Factor	Rush Permit (Dec 2026)	Wait for SB 1117 (Jan 2027+)
Impact Fee Savings	$0 (pay full fees)	$3,250-$14,000 saved
Design Requirements	Must be 100% complete by mid-Dec	More time for optimization
Timeline to Construction	Potentially 2 months faster	Start 2 months later
Risk of Rushed Decisions	Higher (compressed timeline)	Lower (adequate planning time)
Best For	Completed designs + booked crews + timeline priority	Most homeowners (maximize savings)

Recommendation for Most Pacific Beach Homeowners:

Wait for January 2027 submission UNLESS all three conditions are met:

1. Your ADU design, structural engineering, site plans, and coastal compliance are 100% complete and permit-ready by mid-December 2026
2. You have construction crews scheduled and committed to a Q1 2027 start date
3. Your timeline is significantly more critical than saving $3,250-$14,000 in fees

For the vast majority of homeowners, the $3,250-$14,000 in guaranteed savings outweighs the speculative benefits of rushing a December submission. Additionally, rushed design decisions often lead to change orders during construction, which can cost far more than the two-month timeline delay.

Special Considerations for Pacific Beach Coastal Properties:

ADUs in Pacific Beach's coastal zone require Coastal Development Permits. Under AB 462 (effective October 2025), coastal agencies must approve or deny ADU permits within 60 days. If you submit in early January 2027, you could receive coastal approval by early March 2027—still early enough for spring/summer construction starts. Rushing a December 2026 coastal permit application may not provide meaningful timeline advantages while sacrificing thousands in impact fee savings.

Local Ordinance Compliance Deadline: What Happens December 31, 2026

SB 1117 doesn't just create savings opportunities—it imposes strict compliance deadlines on local governments. Understanding these deadlines helps Pacific Beach homeowners know what to expect as January 1, 2027 approaches.

Mandatory Ordinance Updates by December 31, 2026:

SB 1117 requires ALL California cities and counties to update their ADU ordinances to comply with the 750 sq ft exemption mechanism by December 31, 2026. This isn't optional—it's a state mandate with automatic consequences for non-compliance.

Local agencies must:

1. Amend existing ADU ordinances to incorporate SB 1117's fee calculation methodology
2. Ensure ordinances reflect that the first 750 sq ft of each of up to two ADUs is exempt from impact fees
3. Submit adopted ordinance amendments to the California Department of Housing and Community Development (HCD) within 60 days after adoption

Automatic Nullification Provision:

If any jurisdiction fails to update its ADU ordinance by December 31, 2026, that ordinance automatically becomes NULL AND VOID as a matter of law on January 1, 2027. This is an extraordinary enforcement mechanism—the state legislature essentially built in automatic compliance.

Once nullified, California's statewide ADU law (Government Code §§ 65852.2 and 65852.22) governs directly. SB 1117's fee exemption applies automatically whether or not the local jurisdiction has updated its ordinance. This means Pacific Beach homeowners are guaranteed SB 1117 savings starting January 1, 2027 regardless of local government action or inaction.

San Diego's Current Status:

The City of San Diego enacted Resolution 2026-34 on July 20, 2026, which updated the citywide Development Impact Fee Nexus Study and exempted ADUs under 750 sq ft entirely from Parks, Fire, Library, and Mobility impact fees. However, Resolution 2026-34 addresses ADUs under 750 sq ft differently than SB 1117 addresses ADUs over 750 sq ft.

Key questions for San Diego as of November 2026:

• Does Resolution 2026-34's framework satisfy SB 1117's requirement for the partial exemption mechanism (first 750 sq ft of larger ADUs)?
• Will San Diego City Council need to pass an additional ordinance amendment specifically implementing SB 1117's calculation methodology for ADUs exceeding 750 sq ft?
• What is the timeline for any necessary ordinance updates before the December 31, 2026 deadline?

What Pacific Beach Homeowners Should Do:

1. Monitor San Diego City Council agendas in November-December 2026 for SB 1117 ordinance implementation items
2. Contact San Diego Development Services in early December 2026 to confirm ordinance compliance status
3. Request written confirmation of how impact fees will be calculated for ADUs over 750 sq ft starting January 1, 2027
4. If submitting permits in January 2027, explicitly reference SB 1117 and request fee calculations based on the 750 sq ft exemption

Pacific Beach ADU Design Optimization: Sizing for Maximum ROI Under SB 1117

SB 1117's 750 sq ft exemption creates new strategic considerations for ADU sizing. Pacific Beach homeowners should optimize designs to balance impact fee savings, construction costs, rental income potential, and coastal building constraints.

Under 750 Sq Ft ADUs: Maximum Fee Savings Percentage

Advantages:

• 100% exempt from all development impact fees (save $3,900-$6,000 on a 600 sq ft unit)
• Lower construction costs: $168,000-$252,000 for 600 sq ft detached ADU at $280-$420/sq ft
• Smaller footprint fits more Pacific Beach lots with tight setback requirements
• Faster permitting due to simpler plans and reduced square footage

Disadvantages:

• Lower rental income: $2,400-$2,800/month for 600 sq ft units in Pacific Beach
• Tight living space may limit tenant pool (less attractive to couples or professionals)
• Less flexibility for premium finishes or multiple rooms

Best for: Homeowners prioritizing lowest upfront cost, maximum fee savings percentage, or building on constrained lots

800-1,000 Sq Ft ADUs: The Pacific Beach Sweet Spot

Advantages:

• Strong impact fee savings: $3,250-$7,000 depending on size
• Only moderate fees on excess square footage: $650-$3,250 in total impact fees
• Optimal rental income: $3,000-$3,500/month (attractive to single professionals or couples)
• Construction costs remain manageable: $224,000-$420,000 for 800-1,000 sq ft
• Comfortable living space with room for 1-2 bedrooms, full kitchen, full bath
• Fits most Pacific Beach lots within setback and lot coverage limits
• Properties near Tourmaline Surfing Park in Pacific Beach typically benefit from SB 1117 savings of $3,500-$7,000 on 800-1,000 sq ft ADUs, with coastal setback requirements similar to other Pacific Beach coastal properties

Disadvantages:

• Not 100% fee exempt (pay fees on 50-250 sq ft excess)
• Higher construction costs than sub-750 sq ft units

Best for: Most Pacific Beach homeowners seeking optimal balance of cost, savings, rental income, and market appeal

Why 800-1,000 Sq Ft is Optimal:

Pacific Beach's coastal lot constraints typically limit ADUs to 800-1,200 sq ft due to:

• 4-foot side and rear setbacks (or 0-foot if fire-rated construction)
• Maximum lot coverage limits (40-60% depending on zone)
• Coastal Development Permit requirements for design compatibility
• Height limits (16-25 feet depending on zone)

Within these constraints, 800-1,000 sq ft offers the best ROI:

• Fee savings are substantial ($3,250-$7,000)
• Construction cost per square foot remains efficient ($280-$420/sq ft)
• Rental income reaches market-competitive rates ($3,000-$3,500/month)
• Unit size appeals to the broadest tenant pool
• For Pacific Beach properties along Garnet Avenue, Grand Avenue, or near Crystal Pier, the combination of SB 1117 fee savings and strong coastal rental demand creates exceptional ROI opportunities

1,200+ Sq Ft ADUs: Premium Rental Income Strategy

Advantages:

• Premium rental income: $3,500-$4,500/month for 1,200+ sq ft units
• More attractive to families or professionals needing office space
• Potential for 2-3 bedrooms, multiple baths
• Highest resale value if selling property with ADU

Disadvantages:

• Higher impact fees: $5,850-$9,000 for 1,200 sq ft (fees on 450 sq ft excess)
• Substantially higher construction costs: $336,000-$504,000+ for 1,200 sq ft
• May exceed lot coverage limits on smaller Pacific Beach lots
• Longer permitting and construction timelines

Best for: Homeowners with larger lots, higher budgets, and long-term rental income focus

Dual ADU Consideration: Maximizing SB 1117's Two-Unit Benefit

SB 1117's most powerful provision applies to lots building two ADUs—each unit gets its own 750 sq ft exemption. Our team specializes in multi-unit ADU projects that maximize this benefit.

Dual 750 Sq Ft ADUs (1,500 Sq Ft Total):

• Combined rental income: $5,400-$6,000/month ($2,700-$3,000 per unit)
• Impact fees: $0 (both units fully exempt)
• Construction cost: ~$420,000-$630,000 total
• Annual rental income: $64,800-$72,000
• Cash-on-cash return: 10.3-17.1% before appreciation

Dual 800 Sq Ft ADUs (1,600 Sq Ft Total):

• Combined rental income: $6,000-$7,000/month ($3,000-$3,500 per unit)
• Impact fees: ~$1,300-$2,000 (each unit pays fees on 50 sq ft only)
• Construction cost: ~$448,000-$672,000 total
• Annual rental income: $72,000-$84,000
• Cash-on-cash return: 10.7-18.8% before appreciation

Dual ADUs require larger lots (typically 7,500+ sq ft in Pacific Beach) and more complex permitting, but SB 1117's dual exemption makes them significantly more financially attractive than pre-2027 fee structures. North Pacific Beach properties near Kate Sessions Park and Tourmaline Surfing Park often have larger lots suitable for dual ADU projects, maximizing the $9,100-$14,000 dual exemption benefit.

Coastal Development Permit Interaction: AB 462 Streamlining + SB 1117 Savings

Pacific Beach ADU projects benefit from two simultaneous regulatory improvements: AB 462's coastal permitting acceleration (effective October 2025) and SB 1117's impact fee savings (effective January 2027). Understanding how these laws work together helps homeowners and contractors maximize timeline and cost advantages.

AB 462: 60-Day Coastal ADU Permits (Effective October 15, 2025)

Before AB 462, building an ADU in California's coastal zone required a Coastal Development Permit—a process that could take 6-18 months and involve California Coastal Commission appeals. AB 462 transformed this timeline:

• Coastal agencies must approve or deny ADU permits within 60 days of complete application
• Local government decisions on ADU coastal permits are NOT appealable to the Coastal Commission
• If the agency fails to act within 60 days, the ADU is deemed approved automatically

For Pacific Beach, La Jolla, and Mission Beach (all within the coastal zone), AB 462 reduced permitting timelines by 4-10 months compared to pre-2025 processes.

SB 1117: Impact Fee Savings (Effective January 1, 2027)

SB 1117 reduces upfront development costs by $3,250-$14,000 for typical ADU projects through the 750 sq ft impact fee exemption.

Combined Timeline and Cost Benefits:

Pre-AB 462, Pre-SB 1117 (Before October 2025):

• Coastal permit timeline: 6-18 months
• Impact fees (1,000 sq ft ADU): ~$6,500-$10,000
• Total project timeline: 12-24 months from application to construction completion
• Total upfront fees and permits: ~$11,500-$25,000

Post-AB 462, Post-SB 1117 (January 2027+):

• Coastal permit timeline: 60 days (2 months)
• Impact fees (1,000 sq ft ADU): ~$3,250-$5,000 (with SB 1117 exemption)
• Total project timeline: 8-14 months from application to construction completion (4-10 months faster)
• Total upfront fees and permits: ~$8,250-$20,000 ($3,250-$5,000 savings on impact fees alone)

Strategic Submission Timing:

For Pacific Beach coastal ADU projects:

1. Early January 2027: Submit permit application to capture SB 1117 fee savings
2. 60-Day Coastal Review: Receive coastal permit approval by early March 2027 under AB 462's mandatory timeline
3. Spring/Summer 2027 Construction: Start construction in optimal weather months

This timeline captures both SB 1117 savings and AB 462 speed while positioning projects for ideal construction seasons in Pacific Beach's coastal climate.

ROI Analysis: How SB 1117 Fee Savings Accelerate ADU Investment Returns

Impact fee savings translate directly into improved ROI timelines and cash-on-cash returns. Understanding these financial impacts helps homeowners make confident ADU investment decisions and positions contractors as financial advisors, not just builders.

Scenario	ADU Size	Total Cost	Monthly Rent	Payback Period	Cash-on-Cash Return
Without SB 1117	1,000 sq ft	$400,000	$3,000	133 months (11.1 years)	9.0%
With SB 1117	1,000 sq ft	$395,000	$3,000	131.7 months (10.9 years)	9.1%
Optimized with SB 1117	800 sq ft	$318,000	$3,000	106 months (8.8 years)	11.3%
Dual ADUs with SB 1117	Two 800 sq ft	$560,000	$6,500	86 months (7.2 years)	13.9%

Baseline ROI Scenario (Without SB 1117):

• ADU size: 1,000 sq ft
• Construction cost: $400,000 (including design, permits, impact fees, construction)
• Impact fees (pre-SB 1117): $6,500-$10,000
• Monthly rental income: $3,000
• Annual rental income: $36,000
• Simple payback period: 133 months (11.1 years)
• Cash-on-cash return: 9% (not accounting for appreciation or tax benefits)

With SB 1117 Fee Savings ($5,000 Example):

• ADU size: 1,000 sq ft
• Construction cost: $395,000 (saving $5,000 on impact fees)
• Impact fees (with SB 1117): $3,250 (fees on 250 sq ft only)
• Monthly rental income: $3,000 (unchanged)
• Annual rental income: $36,000
• Simple payback period: 131.7 months (10.9 years)
• Cash-on-cash return: 9.1%
• Timeline improvement: 1.3 months faster payback

Compounding Financial Effects:

SB 1117 savings create multiple financial benefits beyond the direct fee reduction:

1. Lower Loan Principal: If financing the ADU, saving $5,000-$12,000 reduces the loan amount, decreasing monthly debt service and total interest paid over the loan term. On a 20-year loan at 7% interest, saving $10,000 upfront reduces total interest by approximately $10,000-$12,000.
2. Improved Debt Service Coverage Ratio: Lower total project costs improve the project's debt service coverage ratio, potentially qualifying homeowners for better loan terms or approval on borderline applications.
3. Reduced Property Tax Basis (Jurisdiction-Dependent): In some California jurisdictions, development impact fees are included in the property tax reassessment basis. Saving $5,000-$12,000 on fees can reduce annual property tax increases by $50-$120 annually (at 1% property tax rate).
4. Cash Flow Flexibility: Saving $5,000-$12,000 upfront provides cash for higher-quality finishes, landscaping, or reserves for maintenance—all of which improve tenant satisfaction, reduce vacancy, and support premium rents.
5. Accelerated Equity Building: Faster payback timelines mean homeowners reach positive equity sooner, enabling cash-out refinancing, HELOCs, or other financial strategies.

Long-Term Appreciation Context:

These ROI calculations focus on rental income payback and don't account for property appreciation—a significant wealth-building component of ADU investments in Pacific Beach. ADUs typically add $150,000-$300,000 in property value (depending on size and quality). Combined with SB 1117 fee savings, the total investment return becomes highly compelling:

• $318,000 ADU construction cost (with SB 1117 savings)
• $36,000 annual rental income
• $200,000 property value increase
• Total 5-year value: $180,000 (rent) + $200,000 (appreciation) = $380,000 return on $318,000 investment
• 5-year total return: 19.5% (not annualized)

SB 1117 improves this calculation by reducing the denominator (total investment) while maintaining the numerator (rental income + appreciation), directly improving ROI percentages.