SB9 Subdivision Experts
Maximize Your Property Value with SB9
Unlock the full potential of your land. We help California homeowners navigate Senate Bill 9 to split their lots, build additional units, and significantly increase property value with professional design and engineering.

Our Stats
California Trusted Architectural & Structural Engineering
Years of Experience
Projects Delivered
Permit Approval Rate
Professional Team Members
Cecilia Home provides licensed architectural and structural engineering services for ADUs, additions, remodeling, wall removals, and permit-ready plans. We make the process simple, clear, and stress-free.
With 20+ years of experience, 2,000+ completed projects, and a 95% approval rate, our California-registered engineers deliver accurate, code-compliant designs trusted by homeowners statewide.
Trust & Collaboration
Turn One Property Into Two. Or Four.
Senate Bill 9 allows eligible homeowners to split their single-family lot into two separate parcels and build up to two units on each.Navigating the eligibility requirements and city ordinances is complex. Our team provides the feasibility analysis, architectural design, and engineering required to execute a profitable SB9 project.






All Featured Projects Are Real, City-Approved Plans
Why You Need This
Why Consider an SB9 Lot Split?
Understanding the risks of going it alone vs. the rewards of professional execution.
Risks of Incorrect Filing
- Most applicants are rejected for incomplete site plansCity planners require precise setbacks and easements on the first try.
- Utility access & setbacks are misunderstood by 80% of homeownersIncorrect utility mapping can kill a project before it starts.
- Costly delays from non-compliant map submissionsEvery resubmission adds weeks or months to your timeline.
Benefits of SB9
- Legally increase property value overnightLot splits allow you to create a new APN, unlocking equity instantly.
- Create a new separate buildable lot to sellSell the new lot to a developer or private buyer for immediate profit.
- Add rental units for long-term passive incomeBuild a duplex or ADUs to generate significant monthly cash flow.
Why Choose Cecilia Home
- In-house SB9 Engineering & Survey TeamWe have 20+ specialists dedicated to subdivision and land planning.
- Direct Communication with City PlannersWe handle all negotiations and corrections directly with the jurisdiction.
- Fast Turnaround for FeasibilityGet a clear "Go/No-Go" answer and Tentative Map strategy quickly.
- Proven Track RecordWe have successfully guided numerous homeowners through the SB9 process.
Our Features
Why Choose Cecilia Home?
Licensed, experienced, and trusted across California—we deliver precise designs, clear communication, and reliable results for every project.
PROFESSIONAL EXPERTISE
Licensed architects and engineers with deep knowledge of California codes, ensuring accurate, compliant, and build-ready designs.
CLIENT-CENTERED APPROACH
Clear communication and personalized guidance at every step, ensuring your vision stays at the center of the project.
COMPREHENSIVE SOLUTIONS
From design to permit approval, we provide complete, end-to-end services that save you time and streamline your project.
QUALITY ASSURANCE
All plans meet California building standards, with rigorous checks to ensure safety, accuracy, and long-term performance.
FAST & EFFICIENT DELIVERY
Our optimized design workflow allows us to deliver complete, permit-ready plans in as fast as 7 days—without compromising quality.
LOCAL EXPERIENCE
Expert understanding of California’s building styles, climate needs, and local city requirements for successful permits.
SB 9 Services
Complete SB 9 Lot Split & Housing Solutions
From feasibility and lot split layouts to two-unit design and permit approvals, we deliver complete SB 9 solutions for California homeowners.

SB 9 Urban Lot Split
Conceptual and permit-ready layouts that split one property into two legal parcels, including new lot lines, access, and basic development potential for each lot.

Two-Unit SB 9 Development
Site planning and building design for SB 9 two-unit projects—such as an existing home plus a new SB 9 unit—coordinated with setbacks, parking, and open-space requirements.

Lot Split with Two New Homes
Architectural and structural plans for creating two separate homes on newly split SB 9 parcels, including massing studies, elevations, and engineering for each unit.

SB 9 Setback & Compliance Study
Detailed analysis of setbacks, easements, utilities, and zoning limits, with buildable area diagrams that show exactly where SB 9 units can be placed on your property.
Our Process
Our Process
Our process is designed to be transparent and efficient, delivering a complete one-stop service from design to final permit approval.
Guidance for your project
Free Consultation
Expert advice on your project needs, budget considerations, and permit requirements.
On-Site Assessment
Precise measurements and site evaluation for accurate project planning.
Design Development
Creating detailed plans and visualizations to bring your vision alive.
Permit Acquisition
Navigating complex approval processes to ensure code-compliant construction.
Construction Support
Ongoing guidance and contractor coordination throughout the building process.
Client Testimonials
Trusted by California Homeowners
Ranked #1 on Thumbtack based on verified reviews from homeowners who relied on our architectural and structural engineering services.
Cecilia Home designed our complete home renovation, explained everything clearly, and delivered detailed plans. Honest, professional, and fairly priced—our HOA now knows exactly how to proceed.
View Verified ReviewTrudy M.
Home Remodeling
Mason delivered exactly what I needed—professional, responsive, and great value. Clear communication throughout the process. I'll rely on him for all future remodeling projects.
View Verified ReviewJoanne D.
Home Remodeling
Mason responded instantly and offered honest guidance on whether my garage conversion would pass city review. Knowledgeable, direct, and trustworthy—I look forward to working with them again.
View Verified ReviewJasper T.
ADU Design
I appreciated their honesty. They explained that my foundation cracks were common in the Bay Area and didn't push unnecessary work. Professional, transparent advice I could trust.
View Verified ReviewArturo S.
Structural Engineering
As a general contractor, I value teams who are responsive and accurate. Cecilia Home delivered clear communication, timely plans, and over-the-counter approval. I highly recommend them.
View Verified ReviewKevin V.
Building Permit Services
Mason gave detailed structural guidance for removing our load-bearing wall, including safety considerations. Quick responses and practical advice that helped us comply with local regulations.
View Verified ReviewJackson B.
Wall Removal
FAQ
SB 9 Questions
Answers to the most common questions about California's Senate Bill 9 lot split law.
Eligibility depends on zoning (single-family), setbacks, hazardous zones, historic districts, utilities, and access requirements. We perform a complete feasibility study to determine qualification before starting the project.
Yes. Both the lot split and new units require comprehensive architectural plans, structural engineering, Title 24 compliance, and detailed site planning to meet SB 9 and local city codes.
Timelines vary by city. Feasibility and design typically take 4–8 weeks, while city review ranges from 8–20 weeks depending on caseload and complexity.
Yes. SB 9 allows lot splits and also permits two residential units per parcel, enabling homeowners to create new income-producing units.
Yes. We prepare the application, submit the plans, respond to reviewer comments, coordinate with planning and building departments, and manage the process until final approval.
No. ADUs fall under separate state laws. SB 9 allows lot splits and additional units on newly created parcels. Many homeowners use SB 9 and ADU laws together to maximize property value.