ADU Builder

ADU Construction in Huntington Beach, CA

Serhal Builders builds ADUs in Huntington Beach, including detached backyard units, garage conversions, attached ADUs and junior ADUs.

Huntington Beach follows California’s state ADU and JADU law, and all ADUs get ministerial review by Building, Public Works and Fire. Properties in the Coastal Zone may also need a Coastal Development Permit, so we check your address early.

We’re a licensed, veteran-owned general contractor (CSLB #1074208) with more than 31 years in construction, and we build ADUs across Orange County.

Full-Service Solutions

Complete ADU Services in Huntington Beach

One licensed contractor from design and permits to the final inspection.

Detached ADUs

A separate backyard home built from the ground up, with its own entrance, kitchen and bathroom.

Garage Conversions

We turn an existing garage into a full living space, often the most budget-friendly way to add a unit.

Attached ADUs

An addition connected to your home with its own entry, kitchen and bath, so family stays close but independent.

Junior ADUs (JADU)

A unit of up to 500 square feet created inside your existing home, with its own entrance.

Design & Floor Plans

In-house design, plans from our design partner, or your own architect’s plans. We work whichever way suits you.

Permits & City Approval

We prepare and submit the permit package and handle plan-check corrections with the city.

Utilities & Systems

Electrical, plumbing, sewer, water and gas tie-ins planned early so there are no surprises mid-build.

Kitchens, Baths & Finishes

Cabinets, counters, tile, flooring and fixtures, all handled by the same team that remodels full homes.

Why Choose Us

Solutions & Benefits

Every lot is different. These are the three ways most homeowners add a unit.

Detached ADU

Attached & JADU

Plans & Permits

Detached ADUs & Garage Conversions

A detached ADU gives you a separate backyard home with its own entry, kitchen and bath. A garage conversion reuses an existing structure and is often the most budget-friendly way to add a unit.

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Attached ADUs & Junior ADUs

An attached ADU connects to your home but lives independently. A junior ADU is up to 500 square feet created inside your existing home, a good fit for family members who want their own space nearby.

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Plans & Permits Your Way

Use our in-house design, our design partner, or plans you already have. We prepare the permit package, respond to plan-check comments and coordinate inspections until final sign-off.

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Local Knowledge

What Huntington Beach Homeowners Should Know

Coastal Zone – ADUs in the Coastal Zone may need a Coastal Development Permit, and the city notes garage conversions there still need to meet minimum parking standards.

State exemption size – The city's ADU summary allows one ADU up to 800 square feet and 16 feet tall with reduced 4-foot side and rear setbacks.

Detached size – New detached ADUs are capped at 1,200 square feet under the city's summary.

Short-term rentals – Short-term rentals are prohibited unless the ADU was legally established before February 19, 2021.

Simple Process

Our Working Process

Building an ADU in Huntington Beach has more steps than a remodel. Our process keeps it clear and manageable.

Consultation & Site Visit: We look at your lot, utilities and goals and recommend the ADU type that fits.

Design & Permits: We design in-house, with our partner, or from your plans, then handle submittal and plan-check corrections with the city.

Construction & Final Inspection: Our crew builds the ADU and coordinates every inspection through to final sign-off.

Service Areas

ADU Construction in Nearby Cities

We also build ADUs in these Orange County cities:

Anaheim Brea Buena Park Costa Mesa Cypress Fullerton Garden Grove Irvine La Habra La Palma Los Alamitos Orange Placentia Santa Ana Seal Beach Stanton Tustin Villa Park Westminster Yorba Linda All ADU Services

Quick Answers

Frequently Asked Questions

Do I need a coastal permit for an ADU in Huntington Beach?

If your property is in the Coastal Zone, you may need a Coastal Development Permit. We check this at the start.

How big can my ADU be in Huntington Beach?

The city's summary allows one ADU up to 800 square feet and 16 feet tall with 4-foot side and rear setbacks, and caps new detached ADUs at 1,200 square feet. Larger or taller units must meet base zoning.

Can I rent my Huntington Beach ADU short-term?

The city prohibits short-term rentals of ADUs unless the unit was legally established before February 19, 2021. Rentals of 30 days or more are fine.

Are you a licensed contractor?

Yes. Serhal Builders is a licensed California general contractor (CSLB #1074208). We're veteran-owned and family-run, with more than 31 years of construction experience.

Do you handle the plans and permits?

Yes. We can design your ADU in-house, work with our design partner, or build from plans you already have. Either way we prepare the permit package and handle corrections with the city.

Can I convert my garage into an ADU?

In most cases, yes. California law generally does not allow cities to require replacement parking when a garage is converted into an ADU. We check your specific property before design.

How do I get started?

Call us at 949-829-4999 or request a quote online. We'll talk through your goals, look at your property and explain which ADU type fits best.

ADU Construction in Huntington Beach, CA