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ADU Construction Contractor San Diego County

Your Backyard Could Be Paying You Monthly

San Diego County homeowners are sitting on untapped value. We turn unused space into permitted, rent-ready units — built to last in this climate, by people who actually show up and finish the job.
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Call: 619-481-7245
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B General Contractor Licensed

We hold the Class B license California law requires to pull ADU permits and serve as prime contractor — so your project is always legal and protected.

In-House Crew, No Subcontractors

Our 7-person crew handles your project start to finish. No strangers showing up unannounced, no accountability gaps, no finger-pointing when something needs fixing.

16 Years of Exterior Expertise

We've spent 16 years mastering siding, stucco, and windows in San Diego County's coastal and inland climates — the skills that determine how long an ADU actually holds up.

10% Military and Senior Discount

San Diego County's military families and seniors get 10% off every project — a real discount on a real investment, not a footnote buried in fine print.

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Accessory Dwelling Unit Builder San Diego County

ADU Construction Built Around Your Property

Adding an accessory dwelling unit to your San Diego County property is one of the smartest financial moves available to homeowners right now. Rental income between $2,000 and $4,000 per month is realistic in this market, and homes with permitted ADUs sell for roughly 35% more on average, according to the National Association of Realtors. What makes or breaks an ADU isn’t the floor plan — it’s the execution. Proper permitting, quality exterior finishes, and a crew that actually knows what they’re doing in San Diego County’s climate are what separate a 30-year investment from a 10-year repair bill. That’s where our 16 years of exterior remodeling experience becomes directly relevant to your project. We hold both a Class B General Contractor license and a Class C33 Painting and Decorating Contractor license — the credentials that legally authorize us to serve as prime contractor on your ADU build, pull all permits ourselves, and handle the exterior finishes that determine how your unit looks, performs, and rents.
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Detached ADU Construction San Diego County

What a Well-Built ADU Actually Gives You

Done right, an ADU in San Diego County isn’t just extra space — it’s a monthly income stream, a property value increase, and a long-term asset your family keeps.

Your ADU generates $2,000–$4,000 per month in rental income in San Diego County's competitive rental market.

Your property value increases 20–35% when a permitted ADU is added, based on current San Diego County market data.

Your exterior finishes are chosen specifically for San Diego County's climate — coastal salt air, inland UV exposure, or fire-risk zone requirements, depending on your location.

Your ADU matches your existing home because the same crew handling framing also handles siding, stucco, windows, and paint — no mismatched materials or rushed finishes.

Your permits are pulled by us, not handed off to you — we handle every submission and coordinate with the relevant San Diego County or City department for your address.

Your project has one point of contact from the first site visit to the final inspection — no rotating faces, no middlemen, no communication gaps.

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Call us or get a free online quote to help us identify your project needs.

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We'll follow up

If you requested an online quote, you can expect a callback within 24-48 hours of your request.

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The floor is yours

Connect with an expert and share all project specifics.

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Plan your project

Like what you hear? We'll provide next steps and expert guidance.

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Garage Conversion ADU San Diego County

Your Garage Might Be the Fastest Path Forward

If you have an existing garage, a garage conversion ADU in San Diego County is often the most cost-effective way to start generating rental income. Typical costs range from $80,000 to $150,000 — significantly less than a full detached build — and the timeline is shorter because the structure already exists. We handle the full scope: structural modifications, insulation, drywall, windows, exterior siding or stucco matched to your main home, and exterior painting. The result is a legal, permitted, rentable unit that looks like it belongs on the property — not like an afterthought someone threw together over a weekend. For homeowners in Escondido, El Cajon, Chula Vista, Santee, and throughout San Diego County who want a faster, more affordable entry point into ADU income, the garage conversion conversation is worth having before you assume a full detached build is your only option.
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Granny Flat Contractor San Diego County CA

Every ADU Type, One In-House Crew

Whether you’re planning a detached backyard cottage, a garage conversion ADU, an attached in-law suite, or a granny flat for an aging parent, the construction requirements are largely the same — and so are the stakes. A poorly finished exterior costs you in rent, in resale value, and eventually in repairs. We build every ADU type across San Diego County, from North County communities like Oceanside, Carlsbad, and San Marcos to East County cities like Santee and La Mesa to South County areas near Chula Vista and National City. We know the local permit offices, the Coastal Overlay Zone requirements for coastal communities, and the fire-resistant material standards for inland and higher-risk areas like Ramona and Alpine. You’re not getting a contractor that learned about San Diego County’s regulations last year. You’re getting 16 years of exterior construction experience applied to a project that actually matters to your financial future.
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Adu Construction FAQs

Common questions about our Adu Construction services

Costs vary significantly depending on the type of ADU and the scope of work involved. In San Diego County, garage conversion ADUs typically run $80,000 to $150,000. Detached ADUs — the backyard cottage or standalone unit — generally fall between $200,000 and $450,000, sometimes more for larger builds or premium finishes. Attached ADUs and in-law suites usually land somewhere in between. California’s construction cost index rose roughly 37% from 2021 to 2024, so quotes from a few years ago will understate today’s real numbers. Permit costs in San Diego County typically add another $6,500 to $21,000 depending on size and type, though impact fees are fully waived for ADUs under 750 square feet under state law. The best way to get a number that’s actually useful for your situation is to start with a site visit — too many variables depend on your specific property, location, and goals.
Yes, always. Any ADU built in San Diego County — whether it’s a detached backyard cottage, a garage conversion, or an attached in-law suite — requires a permit before construction begins. This applies whether you’re in the City of San Diego, Escondido, Chula Vista, Oceanside, or any unincorporated county area. The permit process involves plan check review, inspections at multiple stages, and a final certificate of occupancy before anyone can legally occupy the unit. If you have an unpermitted structure built before January 1, 2020, Assembly Bill 2533 — signed in September 2024 — creates a simplified path to legalizing it. We handle all permit submissions ourselves. A contractor who asks you to pull your own permits is a red flag worth taking seriously.
To legally serve as the prime contractor on an ADU build in California, a contractor must hold a Class B General Building Contractor license from the California State License Board. This is not optional — it’s the legal requirement that authorizes a contractor to pull permits, manage a project involving two or more unrelated building trades, and take full responsibility for the construction. Many exterior contractors lack this license, which means they cannot legally run your ADU project from start to finish. We hold both a Class B General Contractor license and a Class C33 Painting and Decorating Contractor license. You can verify any California contractor’s license status at CSLB.ca.gov — and we’d encourage you to do exactly that before signing anything with anyone.
A realistic timeline for a detached ADU in San Diego County — from initial permit submission through final inspection — is typically six to twelve months. Garage conversions and attached ADUs can move faster because they involve less structural work. The permit review phase is often where timelines stretch, particularly if plan check revisions are required or if your property falls under additional review, such as the Coastal Overlay Zone in communities like Encinitas, Carlsbad, or Oceanside. San Diego County offers year-round construction weather — no winter work stoppages, no freeze-thaw delays, no weather-driven schedule disruptions. A contractor who knows the local permit process and submits clean, complete applications will move faster than one who is learning as they go.
Most single-family residential properties in San Diego County qualify for at least one type of ADU, and California’s regulations have expanded significantly since 2019. The specifics depend on your lot size, zoning designation, setback requirements, lot coverage limits, and whether your property falls under any overlay zones — the Coastal Overlay Zone, for example, adds requirements for properties in communities like Del Mar, Encinitas, and Oceanside. The City of San Diego updated its ADU program in June 2025 to allow four to six ADUs on certain properties depending on lot size. Unincorporated county areas follow County of San Diego regulations, which differ from city rules. The fastest way to find out what’s possible on your specific property is a site visit — we can assess feasibility quickly and give you a straight answer before you invest time or money in a plan that may not work for your address.
In 2025, nearly 100 San Diego County homeowners reported that a Chula Vista-based ADU contractor took out construction loans totaling $15 million in their names for projects that in most cases never started. The California State License Board revoked that contractor’s license in June 2025. The best protection is straightforward: verify the contractor’s CSLB license at CSLB.ca.gov before signing anything. Confirm they hold a Class B General Contractor license — not just a specialty license. Ask whether the work will be done by their own crew or subcontractors. Make sure there’s a written contract with a clear scope, timeline, and payment schedule. Be cautious of anyone who asks for a large upfront deposit before work begins or who asks you to pull the permits yourself. We hold active B General and C33 licenses, carry full insurance, and put everything in writing. You’re welcome to verify all of it before we ever pick up a tool.
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Site Visit and Feasibility Review

We assess your property, confirm what San Diego County regulations allow for your specific address, and give you honest answers before you commit to anything.

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Permit Submission and Plan Approval

We prepare and submit all permit documentation, coordinate with the relevant local department, and move your project through the approval process without putting that burden on you.

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Construction Through Final Inspection

Our in-house crew builds your ADU from framing through exterior finishes, passing each required inspection until you receive your certificate of occupancy.