Known as the “City of Good Living,” San Carlos is the perfect place to expand your property with a beautifully designed Accessory Dwelling Unit (ADU). Whether you want extra living space, rental income, or a place for family, Royalty Builders provides full-service ADU design + build solutions in San Carlos that are tailored, stress-free, and built to last.

From garage conversions to detached guest houses, we handle everything in-house—design, permits, and construction—so your project stays on time, on budget, and on point.

Why Build an ADU in San Carlos?

San Carlos offers a mix of suburban charm and Silicon Valley convenience, making it an ideal location for adding an ADU. With increasing demand for housing and rising home values, ADUs provide practical and financial benefits for homeowners looking to:

• House aging parents or grown children in comfort and privacy

• Generate passive income with a long-term rental unit

• Create a private home office, studio, or wellness space

• Boost property value and resale appeal

• Future-proof your home for multi-generational living

California’s updated ADU laws make it faster and easier to build a legal secondary unit—and San Carlos is fully aligned with those policies.

Full-Service ADU Design + Build in San Carlos

At Royalty Builders, we provide a start-to-finish ADU experience under one roof. No need to hire separate designers, permit consultants, and contractors—we do it all with one expert team who knows San Carlos inside and out.

Our process includes:

• Feasibility Assessment: We evaluate your lot’s layout, access, utilities, and zoning to determine the best ADU options.

• Custom Design: Our in-house design team creates personalized plans that reflect your goals, taste, and property conditions.

• Permitting & City Approvals: We handle all interactions with the City of San Carlos to obtain permits quickly and ensure full compliance.

• Construction Management: Our licensed crews deliver top-quality construction with attention to detail and craftsmanship.

• Final Walkthrough & Support: We make sure every inch of your ADU meets expectations and provide continued support after completion.

We’re proud to build ADUs that blend seamlessly with your home while adding function, flexibility, and long-term value.

Types of ADUs We Build in San Carlos

San Carlos’s diverse residential lots and modern family lifestyles allow for a variety of ADU types. We specialize in:

• Detached ADUs: Standalone backyard cottages ideal for renters, family members, or guests

• Attached ADUs: Built as extensions of your home, offering convenient access and independence

• Garage Conversions: Transform existing garage space into a full living unit—efficient and cost-effective

• Above-Garage Units: Utilize vertical space to add an elevated ADU with views and privacy

• Junior ADUs (JADUs): Convert a portion of your main home into a small, self-contained unit with a separate entrance

We’ll help you determine the best option based on your goals, budget, and property configuration.

How Much Does It Cost to Build an ADU in San Carlos?

ADU costs in San Carlos vary depending on the size, type, finish level, and complexity of the project. On average:

• Garage Conversion: $130,000 – $180,000

• Attached ADU: $200,000 – $350,000

• Detached ADU: $250,000 – $400,000+

• Custom High-End Builds: $500,000 and up

What affects cost:

• Property slope and grading needs

• Utility upgrades and trenching

• Interior finishes and appliances

• Permit and impact fees

• Custom features like vaulted ceilings, skylights, or green building elements

We provide transparent pricing and a free consultation to help you plan with confidence.

ADU Permit Process in San Carlos

San Carlos has adopted state-compliant ADU regulations that allow most homeowners to add a unit more easily than ever before. Our team has extensive experience with San Carlos Planning and Building Departments, ensuring smooth, timely approvals.

We handle:

• Zoning and setback review

• Full plan development and submission

• Plan check responses and city coordination

• Building inspections and final approvals

Our familiarity with local requirements helps you avoid delays and costly mistakes.

Frequently Asked Questions – ADU Services in San Carlos

Q: Can I build an ADU on a small lot in San Carlos?
A: Yes. Most residential lots qualify for at least one ADU, even small ones. We’ll review your site and explain what’s possible.

Q: Will I need to provide additional parking?
A: Not always. Parking requirements may be waived if your home is near transit, which applies to many areas of San Carlos.

Q: How long does the entire ADU process take?
A: Most ADU projects take 6 to 10 months, depending on complexity. This includes design, permitting, and construction.

Q: Can I rent out my ADU for income?
A: Yes! Long-term rentals are allowed. Short-term rentals (e.g., Airbnb) may be subject to local restrictions.

Q: What size ADU can I build?
A: Typically up to 1,200 sq. ft., depending on lot size, zoning, and configuration.

Why Choose Royalty Builders for Your San Carlos ADU?

• 🏗 Experienced Design + Build Firm

• 📍 Local Knowledge of San Carlos Regulations

• ✨ Beautiful Custom Designs that Fit Your Home

• 🛠 High-Quality Construction by Skilled Crews

• ✅ End-to-End Management for a Stress-Free Experience

• 🌟 Proven Success Across the Peninsula

We bring reliability, creativity, and attention to detail to every ADU project in San Carlos.

Ready to Build Your ADU in San Carlos?

If you’re ready to expand your property with a high-quality, custom-designed ADU, the team at Royalty Builders is here to help. Schedule your free consultation and discover what’s possible on your lot—whether you’re building for family, income, or lifestyle.

Call us today and schedule a free consultation.