Union City is a growing and vibrant East Bay community where homeowners are embracing smarter ways to increase their property’s functionality and value. One of the most impactful ways to do that? Building an Accessory Dwelling Unit (ADU). Whether you need a home for aging parents, a private rental unit, or your own office or studio space, an ADU can transform your home’s possibilities.

At Royalty Builders, we provide full-service ADU design and construction in Union City—from initial planning and permits to final construction. With our expert team by your side, you’ll get more space, more options, and more peace of mind.

Types of ADUs We Build in Union City

At Royalty Builders, we design ADUs around your lifestyle and your property. Whether you’re expanding your home’s footprint or converting an existing space, we’ll help you choose the right type of ADU and customize it for beauty, efficiency, and compliance.

We specialize in:

• Detached ADUs – Standalone backyard homes for rentals, guests, or multigenerational living

• Attached ADUs – Connected additions to your main residence—perfect for family living

• Garage Conversions – Turn existing garages into functional, code-compliant living space

• Above-Garage ADUs – Add usable square footage by building upward

• Basement ADUs – Unlock underutilized space with a comfortable and legal basement suite

Each ADU we build in Union City meets California and local regulations—and reflects your unique vision.

Full-Service ADU Design + Build in Union City

Our design-build model means you get one experienced team handling every aspect of your project. No need to coordinate between architects, engineers, and contractors—we handle it all under one roof.

Our full-service ADU process includes:

• Feasibility and zoning analysis

• Custom architectural design and 3D modeling

• Structural engineering and energy code compliance

• Complete permit management with the City of Union City

• High-quality construction and finishing

• Final walkthrough, inspections, and occupancy clearance

We provide consistent updates, clear timelines, and one point of contact—so you’re always in the loop.

How Much Does It Cost to Build an ADU in Union City?

ADU pricing in Union City varies depending on your lot, the type of unit, materials, and site conditions. At Royalty Builders, we pride ourselves on clear, itemized estimates—so you know exactly what you’re paying for.

Average cost ranges in Union City:

• Garage Conversion: $120,000 – $170,000

• Attached ADU: $180,000 – $290,000

• Detached ADU: $200,000 – $350,000+

• Above-Garage ADU: $220,000 – $360,000

We also help homeowners explore financing options, including renovation loans and home equity strategies that can make your project more accessible.

Permits for ADU Construction in Union City – What You Need to Know

Union City follows California’s streamlined ADU policies but still requires compliance with local building codes and site-specific zoning. Our experienced permitting team ensures your project gets approved quickly and smoothly.

We handle:

• Site assessment and setback verification

• Design plan preparation and engineering

• Complete permit submittals and revisions

• Coordination with Union City building and planning departments

• Utility tie-ins and final inspections

We’ve worked extensively with the City of Union City—and we know how to keep your project moving forward.

Why Build an ADU in Union City?

Union City offers great schools, a central Bay Area location, and increasing property values. With demand for flexible housing rising, ADUs offer both personal convenience and real investment potential.

Here’s why more Union City homeowners are building ADUs:

• 🏘 Multigenerational living made easy – Separate space for loved ones

• 💼 Home office or studio – Dedicated work-from-home solutions

• 💰 Rental income – Offset your mortgage with long-term tenants

• 📈 Increased resale value – Add livable square footage and market appeal

• 🔄 Flexible future use – Age in place, downsize, or host guests with ease

With ADU-friendly regulations and rising demand, there’s never been a better time to build.

Frequently Asked Questions – ADUs in Union City

Q: What is the maximum ADU size allowed in Union City?
A: In most cases, up to 1,200 sq. ft. is allowed for a detached ADU. Lot size, setbacks, and zoning may affect the maximum. We’ll confirm during your consultation.

Q: Do I need to provide extra parking for an ADU?
A: Often, no. Parking requirements may be waived depending on proximity to transit and other conditions. We’ll verify this for your address.

Q: How long does the process take from start to finish?
A: Most ADU projects take 6–10 months from planning to completion. We provide a personalized timeline based on your project’s scope.

Q: Can I legally rent my ADU?
A: Yes, Union City allows long-term rentals of permitted ADUs. We ensure your unit is fully code-compliant for rental use.

Contact Royalty Builders – Union City’s Local ADU Experts

Are you ready to expand your space, increase your home’s value, or plan for future flexibility? Let Royalty Builders help you design and build the perfect ADU in Union City—seamlessly and stress-free.

📞 Contact us today and schedule your free ADU consultation in Union City.

More freedom. More value. Built right—with Royalty Builders.