Best ADU Builders in San Diego (2026)

San Diego County is one of the most active ADU markets in California — over 2,700 permits issued in 2023 alone, roughly 30% of all new housing permits in the county. That volume attracts both excellent builders and unlicensed operators looking to cash in. This guide lists the best ADU builders in San Diego who have passed our independent CSLB verification: active license, bond on file, workers’ compensation confirmed, and no unresolved complaints.

Every builder featured here appears in our full San Diego ADU builder directory, which is checked automatically against CSLB public records. If a license status changes, the listing updates the same day.

ADU projects in San Diego typically cost $90,000 to $380,000. At that price point, hiring the wrong contractor can mean losing tens of thousands of dollars with no legal recourse.

California’s ADU boom has brought a wave of new contractors into the market — some legitimate, some not. CSLB logs hundreds of ADU-related complaints each year statewide. The pattern is consistent: unlicensed or underinsured contractor takes a deposit, does partial work or none at all, and the homeowner has no bond to file a claim against.

The minimum you should verify before hiring any ADU builder in San Diego:

• Active CSLB license with a B (General Building) classification
• Contractor bond on file — required by California law, provides financial protection if work is abandoned
• Workers’ compensation insurance — protects you from liability if a worker is injured on your property
• Clean complaint history — no unresolved CSLB complaints or disciplinary actions
• General liability insurance — protects against property damage during construction

Every builder listed below meets all of these standards. You can verify any contractor’s license independently at cslb.ca.gov.

This is not a paid list. Builders cannot pay to be featured. Our selection criteria:

• CSLB verification passed — active license, bond, workers’ comp, clean record
• ADU-specific experience — the builder explicitly offers ADU services, not just general contracting
• Google reviews with ADU mentions — real homeowners describing real ADU projects
• Established business — operating for multiple years with a track record
• San Diego County service area — physically located in or actively serving SD County

Builders are listed in no particular order. We don’t rank them — that’s a decision only you can make based on your project scope, budget, and location within San Diego County.

Lusso Design and Build

CSLB #1108702 · Active · San Diego · 5.0★ (57 reviews)

Lusso Design and Build holds a perfect 5.0 rating across 57 Google reviews — a strong score at that volume. They operate as a design-build firm offering ADU construction, home remodeling, and custom residential projects throughout San Diego County. Their ADU work covers detached backyard units, garage conversions, and full home additions.

Reviewers consistently mention design quality and communication throughout the project. For homeowners who want an ADU that matches the aesthetic of their primary home — not just a box in the backyard — Lusso is worth a conversation.

View Lusso Design and Build profile

Kanna Construction & Remodeling

CSLB #1067407 · Active · San Diego · 4.9★ (52 reviews)

Kanna Construction is a San Diego-based general contractor offering ADU construction alongside kitchen and bath remodeling, room additions, and complete renovations. With 52 reviews and a 4.9-star rating, they have a solid track record across a range of residential projects.

Their ADU-related reviews describe smooth permit coordination with the City of San Diego Development Services Department and clean, organized job sites. The company handles projects throughout San Diego proper, La Jolla, and the surrounding communities.

View Kanna Construction profile

Woolsey Construction

CSLB #900515 · Active · San Diego · 5.0★ (33 reviews)

Woolsey Construction is a luxury-focused San Diego builder with a 5.0 Google rating. They specialize in high-end ADU design and construction, custom homes, and major renovations. Their ADU work leans toward the premium end of the market — larger units with upgraded finishes, custom cabinetry, and integrated outdoor living spaces.

If your budget is at the higher end of the range and you want a unit that functions as a standalone guest house rather than a basic rental, Woolsey has the portfolio to back it up. They serve San Diego and the coastal communities.

View Woolsey Construction profile

Ritz ADU Design Build

CSLB #239311 · Active · San Diego · 4.8★ (18 reviews)

Ritz ADU is one of San Diego’s dedicated ADU companies — their entire business is built around accessory dwelling units. They offer a streamlined design-build process with pre-designed floor plans and custom options, covering detached ADUs, garage conversions, attached additions, and JADUs throughout San Diego County.

The focused ADU model means they’ve developed repeatable processes for San Diego permitting and utility connections. Reviewers note fast turnaround on the design phase and transparent pricing with no hidden fees.

View Ritz ADU Design Build profile

CRS Builders Inc.

CSLB #1041423 · Active · San Diego · 5.0★ (13 reviews)

CRS Builders holds a 5.0 Google rating and focuses on ADU construction and residential remodeling in San Diego. They handle the full scope — architectural plans, engineering, permitting, and construction — as a single point of contact.

Their reviews highlight professionalism and attention to detail during the finish phase. For homeowners building rental ADUs who want a unit that attracts quality tenants, the finish quality matters more than most people realize.

View CRS Builders profile

Elevated Remodeling

CSLB #906490 · Active · San Diego · 5.0★ (26 reviews)

Elevated Remodeling operates in San Diego with a 5.0 Google rating across 26 reviews. They offer ADU construction, garage conversions, and home additions. The company takes a design-build approach, managing the project from initial concept through final inspection.

Reviewers describe efficient communication and a structured process that keeps the project moving without surprises. They serve most of San Diego County including the inland communities of Poway, Escondido, and El Cajon.

View Elevated Remodeling profile

JDC Build

CSLB #1071346 · Active · San Diego · 5.0★ (12 reviews)

JDC Build is a San Diego contractor offering ADU construction, home renovations, and custom builds. With a 5.0 rating and ADU-specific project experience, they handle both new detached ADUs and conversion projects. The company serves San Diego proper and the surrounding coastal and suburban communities.

Their reviews reference clear timelines and budget adherence — two factors that matter most when you’re financing an ADU project and need the rental income to start on a specific date.

View JDC Build profile

This is not a complete list. View all 31 verified San Diego builders in our full San Diego ADU directory.

San Diego’s ADU market has distinct characteristics that set it apart from Los Angeles and Sacramento:

• 2,700+ ADU permits issued in 2023 — approximately 30% of all new housing permits in the county
• ADU construction costs: $90,000 (garage conversion) to $380,000 (large detached)
• Average detached ADU cost: $230,000 to $280,000 for 500 sq ft
• Permit timeline: 4 to 8 weeks through the City of San Diego — faster than most California cities
• Monthly rental income: $1,300 to $2,800 depending on size and neighborhood
• Coastal Zone: Properties in La Jolla, Del Mar, Encinitas, Carlsbad, and Oceanside face additional Coastal Commission review requirements

San Diego’s climate advantage means year-round construction with virtually no weather delays — a factor that makes project timelines more predictable than in Northern California markets. For a detailed cost breakdown, see our ADU Cost in San Diego — 2026 Guide.

Beyond CSLB verification, here’s what to evaluate when choosing a San Diego ADU builder:

1. Get 3 to 5 bids. San Diego’s ADU market has significant pricing variation between contractors. Compare the scope of work in each bid — not just the bottom line. The cheapest quote often means cut corners or incoming change orders.

2. Ask about Coastal Zone experience. If your property is in the California Coastal Zone, your builder needs experience navigating the Coastal Development Permit process. This is a separate review layer that adds time and cost. Ask how many Coastal Zone ADU permits they’ve handled.

3. Confirm City vs. County jurisdiction. The City of San Diego and unincorporated San Diego County have different permitting processes, fees, and review timelines. Make sure your builder knows which jurisdiction applies to your property and has permitted in that jurisdiction before.

4. Ask for ADU-specific references. General remodeling experience doesn’t equal ADU experience. The permitting, utility connections, and site work for an ADU are different from a kitchen remodel. Ask to speak with homeowners who’ve had ADUs built.

5. Get a fixed-price contract. Avoid cost-plus contracts. A fixed-price contract protects you from the change order creep that blows ADU budgets. If a builder won’t commit to a fixed price, that’s a signal.

6. Check the CalHFA grant first. The $40,000 CalHFA ADU grant covers pre-development costs and can offset a significant portion of your upfront expenses. Apply before you sign a construction contract. Read our CalHFA grant guide for details.

Who are the best ADU builders in San Diego?

The best ADU builders in San Diego include Lusso Design and Build, Kanna Construction, Woolsey Construction, Ritz ADU Design Build, CRS Builders, Elevated Remodeling, and JDC Build. All hold active CSLB licenses with bond and workers’ comp confirmed. See our full verified San Diego builder directory for all 31 listings.

How do I verify an ADU builder’s license in San Diego?

Check the contractor’s CSLB license number at cslb.ca.gov. Confirm the license is active, the classification includes B (General Building), a contractor bond is on file, and workers’ compensation insurance is current. VerifiedADU checks all of these automatically for every listed builder.

How much does an ADU cost in San Diego?

ADU costs in San Diego range from $60,000 for a JADU to $380,000 for a large detached unit in a coastal neighborhood. The average 500 sq ft detached ADU costs $230,000 to $280,000. See our ADU Cost in San Diego guide for detailed breakdowns.

How long does it take to build an ADU in San Diego?

From permit submission to completion, most San Diego ADU projects take 8 to 14 months. The City of San Diego typically processes permits in 4 to 8 weeks — faster than most California cities. Construction takes 4 to 8 months for site-built ADUs or 2 to 4 months for prefab units.

Do I need a licensed contractor to build an ADU in San Diego?

Yes. California law requires a licensed contractor for any construction project valued over $500. ADU projects in San Diego range from $60,000 to $380,000, so a CSLB-licensed contractor with a B (General Building) classification is required. Hiring an unlicensed contractor is illegal and voids most insurance protections.

Is San Diego cheaper than LA for ADU construction?

Yes. San Diego is typically 10% to 20% cheaper than Los Angeles for equivalent ADU projects. Lower labor rates, faster permitting, and fewer hillside complications contribute to the cost difference. A 600 sq ft detached ADU costs $230,000 to $280,000 in San Diego versus $280,000 to $350,000 in LA.

Can I build an ADU in the San Diego Coastal Zone?

Yes, but properties in the California Coastal Zone may require a Coastal Development Permit in addition to the standard building permit. This adds $3,000 to $8,000 in fees and 2 to 6 months to the timeline. Affected areas include La Jolla, Del Mar, Encinitas, Carlsbad, and Oceanside.

What ADU types can I build in San Diego?

San Diego allows detached ADUs (up to 1,200 sq ft), attached ADUs (up to 1,200 sq ft or 50% of primary dwelling), JADUs (up to 500 sq ft within existing home), and garage conversions. Most single-family lots can have one ADU and one JADU. No replacement parking is required for any ADU type under current California law.