Fullerton
ADU BuilderIn Fullerton, CAAnd Orange County
NewGen ADU Builders is a licensed, insured and bonded ADU builder in Fullerton, about 8 miles east of Cerritos, backed by a 1-year workmanship warranty.
01 — Services
What We Build in Fullerton
Every ADU service we offer is available in Fullerton. Its established neighborhoods and larger lots suit detached ADUs, and steady rental demand near the university makes a new unit a practical investment. We design and build the unit to fit the lot, the main house, and the budget you set.
- 01
Garage Conversion
Turn an existing garage into a finished living unit with its own kitchen, bath, and entrance. Often the fastest route to an ADU on a Fullerton lot because the structure already exists.
Learn More - 02
Storage Room Conversion
Convert a workshop, storage building, or similar structure into a complete ADU after an honest on-site assessment.
Learn More - 03
New Ground-Up ADU Construction
Build a new unit from the foundation up when no existing structure fits or you want a specific layout.
Learn More - 04
Detached ADU
A standalone backyard home offering the most privacy for tenants or family.
Learn More - 05
Attached ADU
A new unit that shares a wall with your home, a strong fit for Fullerton lots without room for a separate structure.
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02 — Local Market
ADUs in Fullerton:The Local Numbers
Fullerton homeowners are building ADUs, and the public record shows it. These are the city's own home value, rent, and permit numbers, plus what appraisal research says ADUs add.
$1,039,798
Typical Fullerton home value
Zillow Home Value Index, August 2026
+29.2%
Change in typical home value over five years
Zillow Home Value Index, August 2021 to August 2026
$2,917
Typical monthly rent in Fullerton, all rentals
Zillow Observed Rent Index, August 2026
610
ADU building permits issued in Fullerton, 2021 to 2025, as reported to the state
California HCD Annual Progress Reports
What the research shows
Statewide, appraisal data from the Federal Housing Finance Agency shows California properties with an ADU had a median appraised value of $1,064,000 in 2023, against $715,000 for properties without one. FHFA notes the higher growth in appraised value for properties with ADUs requires further analysis, so this is a comparison of medians, not a promise for any one home. A peer-reviewed study of Los Angeles found that ADU presence raises a parcel's assessed value and selling price by 7% to 9%. Both are statewide or City of Los Angeles figures, not Fullerton-only numbers, and Fullerton is in Orange County.
What the local record shows
Typical home values in Fullerton are up 29.2% over five years, and typical rent is $2,917 a month. Of the ten cities in our service area, Fullerton has the second-highest typical home value. Fullerton reported 610 ADU building permits issued from 2021 to 2025.
See the City of Fullerton's ADU pageSources · data retrieved 2026-09-21
- Zillow Research — Home Value Index and Observed Rent Index for Fullerton, CA, data through August 2026, and the same series for the other nine service-area cities used in the comparison
- California HCD — Housing Element Annual Progress Reports, Table A2, ADU building permits issued in Fullerton, 2021 to 2025, by permit issue date with repeat reports removed
- FHFA — Trends in Median Appraised Value for Properties With ADUs in California, published 2025-01-02
- Brueckner and Thomaz — ADUs in Los Angeles: Where are they located and by how much do they raise property value? Real Estate Economics, 2024
- City of Fullerton — Accessory Dwelling Units ("Granny Units")
03 — Process
How It Works in Fullerton
- 01
Consult
Text, call, or send the form for your free ADU property and investment analysis. We review your Fullerton property, its site conditions and utilities, then walk through your goals, budget, and preliminary feasibility.
- 02
Design
We develop the concept and finish selections for your project and coordinate architectural and engineering work based on the final scope, then deliver a written estimate you approve before we move to permitting.
- 03
Permit
We submit for plan check and coordinate every permit requirement with the City of Fullerton so your project is fully approved before construction starts.
- 04
Build
From foundation and framing through MEP and finishes, we manage the defined scope, selections, and schedule, with inspections at every stage. Construction runs 3 to 6 months.
- 05
Turnover
Final inspection, punch-list completion, and a complete handoff of your finished ADU in Fullerton, backed by our 1-year workmanship warranty.
04 — Why Choose Us
Why FullertonHomeowners Choose Us
Based Minutes Away in Cerritos
Fullerton is about eight miles east of Cerritos in north Orange County, inside our range for site visits and builds. Site visits are easy to schedule and we are close by throughout the build.
Licensed, Insured & Bonded
Your property is protected throughout the build, and documentation is available on request.
Honest, Transparent Pricing
Most projects fall between $120,000 and $340,000, and we tell you where yours lands before you commit.
1-Year Workmanship Warranty
If anything we built needs attention in the first year, we come back and fix it.
ADUs Are All We Do
Garage conversions, storage conversions, and new attached and detached units are our entire business.
05 — Get Started
Ready to Start Your ADUin Fullerton?
Reach out and we will schedule a short intake call, then come to your Fullerton property for a free on-site visit and written estimate.
- Free on-site estimates in Fullerton
- Licensed, insured and bonded
- 1-year workmanship warranty
- Text us at (562) 308-6040
06 — FAQ
Common Questions fromFullerton Homeowners
Do you serve all of Fullerton?
Yes. Fullerton is well inside our 30-mile range from Cerritos, and we serve every neighborhood, including the neighborhoods around Downtown Fullerton, Sunny Hills, and the Cal State Fullerton campus.
How soon can you visit my property in Fullerton?
We start with a short intake call, then schedule the on-site visit. Because Fullerton is close to our Cerritos home base, visits are easy to fit in. The call and visit are free and carry no obligation.
How much does an ADU cost in Fullerton?
Our projects run between $120,000 and $340,000. Conversions sit at the lower end and new detached construction at the upper end. You get a written estimate after the on-site visit.
How do I get started if I am in Fullerton?
Text or call (562) 308-6040 or send the form. We set up a short intake call, then schedule your on-site visit.
What should I compare when I'm getting bids from other ADU builders?
Before you compare bids, compare scope. Ask every builder to spell out, in writing, who is responsible for design and engineering, utility and electrical-service work, and foundation and structural scope; what cabinet, counter, flooring, and tile allowances are included; who handles permit and inspection responsibilities and site concrete, drainage, and exterior work; what the change-order process and exclusions are; and what your completion, punch-list, and warranty responsibilities look like. We put all of it in writing before you sign.
07 — Service Area
Serving Fullerton andSurrounding Areas
Fullerton is one of the nine cities closest to our Cerritos headquarters, and part of the Orange County side of our range. Near the edge of our range? Text us and we will confirm.
Based in Cerritos and proud to serve Fullerton. Get your free ADU estimate today.