Nestled on the Peninsula between San Mateo and Redwood City, Belmont offers peaceful, suburban charm with close proximity to everything the Bay Area has to offer. For homeowners looking to expand their living space, accommodate family, or create a rental income stream, building an Accessory Dwelling Unit (ADU) is one of the smartest investments you can make.

At Royalty Builders, we specialize in custom ADU design and construction in Belmont—from initial site assessment to final inspection. Whether you’re considering a detached unit for parents, a garage conversion for a tenant, or a backyard studio for your work-from-home lifestyle, we handle everything with precision, transparency, and care.

🛠️ Full-Service ADU Design + Build in Belmont

With Royalty Builders, you get more than just a contractor—you get a dedicated team that manages your project from start to finish. Our in-house designers, permit experts, and construction pros work seamlessly to bring your vision to life.

✅ Feasibility Assessment & Site Evaluation – We examine your property to confirm buildable space, access, and zoning compliance
✅ Custom ADU Design – Your unit is tailored to your property, goals, and Belmont’s architectural standards
✅ Permitting & City Coordination – We handle the entire permitting process with the City of Belmont
✅ High-Quality Construction – Built with care, craftsmanship, and long-lasting materials
✅ Final Walkthrough & Compliance – We don’t just build—we deliver move-in ready, legally approved ADUs

We pride ourselves on clear communication, accurate timelines, and delivering exceptional results on every project.

🧱 Types of ADUs We Build in Belmont

Our ADUs are fully customizable based on your lot size, home layout, and how you intend to use the space:

• Detached ADUs – Standalone backyard units perfect for family, guests, or renters

• Garage Conversions – Convert an existing garage into a fully functional living space

• Attached ADUs – Add a new wing to your home with a separate entrance

• Above-Garage ADUs – Utilize vertical space for a stylish, elevated apartment

• Junior ADUs (JADUs) – Small units (under 500 sq. ft.) created within your existing home’s footprint

📍 Why Build an ADU in Belmont?

Belmont is a prime location for ADU development—offering privacy, strong home values, and supportive zoning policies. Whether your goal is to increase property value, support your family, or earn extra income, an ADU is a smart step forward.

✔️ Create Multi-Generational Living Solutions – Keep family close while maintaining independence
✔️ Generate Passive Rental Income – Take advantage of Belmont’s strong demand for housing
✔️ Add Home Office or Hobby Space – Quiet, detached areas perfect for remote work or creative pursuits
✔️ Boost Property Value – ADUs significantly increase resale potential
✔️ Benefit from State-Backed ADU Laws – California’s streamlined ADU policies make it easier than ever to build

💲 ADU Construction Costs in Belmont

The cost of building an ADU in Belmont depends on the size, type of unit, and site conditions. Here’s a general range:

• Garage Conversions: starting from $90,000–$160,000

• Detached ADUs: typically range from $200,000–$400,000+

• Attached ADUs: usually fall between $175,000–$300,000

• Above-Garage Units: may cost $225,000–$375,000+ due to structural reinforcement and access

📌 We provide detailed, line-item estimates so you know exactly what to expect—and we’ll help you explore financing options if needed.

📝 Permits for ADU Construction in Belmont – What to Expect

While the State of California has passed ADU-friendly laws, each city—including Belmont—retains local control over design standards, setbacks, and permitting procedures. That’s why working with an experienced contractor like Royalty Builders is so important.

Here’s how we guide you through the Belmont ADU permitting process:

🔹 Zoning & Property Review
We verify that your lot meets Belmont’s residential zoning criteria and check setback, height, and coverage limits. Most single-family homes qualify for at least one ADU.

🔹 Architectural Review (If Required)
Depending on your ADU’s location or size, you may be required to undergo a design review to ensure architectural consistency with your neighborhood. We handle all submittals and adjustments.

🔹 Permit Submittal & Coordination
We prepare and submit your entire permit package, including architectural drawings, Title 24 energy compliance, site plans, and structural details. We coordinate with Belmont’s Building and Planning Departments to ensure a smooth process.

🔹 Plan Review & Approvals
We respond quickly to any correction notices or comments from the city. Belmont is required to issue approvals within 60 days for most ADU applications under California law.

🔹 Inspections & Final Certificate
After construction, we arrange all required city inspections and obtain your Certificate of Occupancy—making your ADU fully legal and move-in ready.

✅ Our deep understanding of Belmont’s local ordinances allows us to move your project forward efficiently—minimizing delays and keeping your timeline on track.

👷 Why Choose Royalty Builders as Your Belmont ADU Contractor?

We know Belmont. We know ADUs. And most importantly—we know how to get things done right the first time. With Royalty Builders, you get a local team that values craftsmanship, communication, and customer satisfaction.

Here’s what sets us apart:

• 🏗️ Full-Service Design + Build

• 🧭 Zoning & Permit Expertise in Belmont

• 🛠️ Top-Tier Construction & Materials

• 📋 Detailed Estimates, No Hidden Fees

• 🤝 Dedicated Project Manager From Start to Finish

Whether you’re building for family, income, or lifestyle, we’ll help you unlock your property’s potential—beautifully and legally.

❓ FAQ – ADU Services in Belmont

Q: Can I build an ADU and a Junior ADU (JADU) in Belmont?
A: Yes! Most single-family lots in Belmont allow one detached ADU and one JADU within the existing home, subject to certain conditions.

Q: Do I need to provide extra parking for my ADU?
A: Often no. Parking requirements are waived in many cases, especially if your property is near public transit or if you’re converting existing space.

Q: What size ADU can I build in Belmont?
A: Detached ADUs can be up to 1,200 sq. ft., depending on your lot size and configuration.

Q: How long does it take to get permits?
A: Most ADU permits are issued within 60 days, per California law. Our team expedites the process wherever possible.

📞 Contact Us – Start Your Belmont ADU Today

Ready to build an ADU that brings freedom, flexibility, and lasting value to your Belmont property? Let’s make it happen—together.

📞 Call us today and schedule your free consultation.

At Royalty Builders, we don’t just build ADUs—we build solutions for real life, right where you live.