South San Francisco ADU Contractor – Full-Service Design + Build by Royalty Builders
Looking to add more living space or generate passive income on your South San Francisco property? With housing demand at an all-time high, building an Accessory Dwelling Unit (ADU) is one of the smartest upgrades you can make. At Royalty Builders, we offer full-service ADU design + build solutions tailored for South San Francisco homeowners—helping you create a functional, attractive, and fully permitted unit on your property.
From garage conversions to detached backyard homes, we manage the entire process—from concept to completion—with unmatched attention to detail and customer care.
Why Build an ADU in South San Francisco?
With its central location near San Francisco, Silicon Valley, SFO, and major tech campuses, South San Francisco is a hub for commuters and families alike. Building an ADU allows you to:
Add flexible living space for extended family or guests
Create a long-term rental unit to offset your mortgage
Build a home office, gym, or creative retreat
Increase your property’s value and future resale appeal
Support multi-generational living without compromising privacy
Thanks to California’s pro-ADU legislation, South San Francisco now offers a streamlined process for homeowners to legally add these units—making it easier than ever to maximize your property’s potential.
Full-Service ADU Design + Build in South San Francisco
At Royalty Builders, we provide end-to-end ADU services under one roof. We handle everything—site analysis, design, permits, construction, and inspection—so you can focus on your vision while we bring it to life.
Here’s how we work:
Feasibility Study: We evaluate your lot, access, slope, and utility connections to determine what’s possible.
Custom Design Plans: Our in-house designers create a plan that complements your main home and fits your goals.
Permitting & Approvals: We manage the full permit process with South San Francisco’s Planning and Building Departments.
Construction: Our skilled builders deliver high-quality work on time and within budget.
Post-Construction Walkthrough: We review every detail with you and remain available for support long after the project is finished.
We make the ADU process smooth, fast, and fully customized.
Types of ADUs We Build in South San Francisco
Depending on your property, lifestyle, and budget, we offer a variety of ADU types:
Detached ADUs: Backyard cottages or self-contained rental units
Attached ADUs: Additions to your existing home with a private entrance and full amenities
Garage Conversions: Efficiently convert your garage into a full living space
Above-Garage Units: Add a second-story living space over your garage for additional privacy and functionality
Junior ADUs (JADUs): Create a compact living space within your home using existing square footage
We’ll help you choose the right layout and location based on your goals and property features.
How Much Does It Cost to Build an ADU in South San Francisco?
ADU costs vary based on the size, structure type, design features, and site conditions. Here are general price ranges:
Garage Conversion: $130,000 – $180,000
Attached ADU: $200,000 – $350,000
Detached ADU: $250,000 – $400,000+
High-End Custom ADUs: $500,000 and up
What affects cost:
Lot slope and grading
Utility upgrades (sewer, water, electric)
Foundation work and drainage
Interior finish level and appliances
Smart home features or solar systems
Permitting and development impact fees
We provide clear estimates and no surprises, helping you make informed decisions from the start.
ADU Permit Process in South San Francisco
The City of South San Francisco follows California ADU mandates, which means they must allow most legal ADUs with streamlined processing. Royalty Builders takes care of the entire process so you don’t have to worry about zoning codes, forms, or back-and-forth with the city.
We manage:
Zoning review and setback checks
Preparation of full plan sets
Permit applications and submittals
Plan check corrections
Scheduling inspections and final approvals
We stay current with all local and state ADU guidelines, so your project is always in full compliance.
Frequently Asked Questions – ADU Services in South San Francisco
Q: Can I build an ADU on a small lot in South San Francisco?
A: Yes! Most residential lots qualify under state law. We’ll help you determine what’s feasible on your property.
Q: How big can my ADU be?
A: Typically up to 1,200 sq. ft., depending on your lot size and ADU type. We’ll maximize your space while staying compliant.
Q: Can I rent out my ADU?
A: Yes. ADUs are legal long-term rentals. Short-term rentals may be restricted, so we’ll guide you based on current rules.
Q: How long does the process take?
A: Most projects take 6 to 10 months, including design, permits, and construction.
Q: Will I need extra parking for my ADU?
A: Often no. Parking requirements are waived in many parts of South San Francisco if you’re near public transit.
Why Choose Royalty Builders for Your South San Francisco ADU?
🏗 Complete Design + Build Services
📍 Local Knowledge of South San Francisco Codes & Permits
✍️ Custom Floorplans Tailored to Your Needs
🛠 Top-Quality Materials & Construction
✅ On-Time, On-Budget Project Management
🌟 Trusted by Bay Area Homeowners
We’ve helped dozens of families create stunning ADUs across the Peninsula—and we’re ready to help you next.
Ready to Build an ADU in South San Francisco?
Let’s turn your backyard or garage into a beautiful, functional living space. Contact Royalty Builders today to schedule your free ADU consultation and start planning your project.
Call us today and schedule a free consultation.
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