Types of ADUs We Build
Detached ADU
A standalone structure on your property — fully separate from the main home. Ideal for rental income or multi-generational living.
Attached ADU
An addition to the main home with a separate entrance. More cost-effective and faster to permit than a detached unit.
Garage Conversion ADU
Convert an existing garage into a permitted living space. Often the fastest and most affordable ADU option.
Junior ADU (JADU)
A unit within the existing home footprint, up to 500 sq ft. Limited construction — good for a bedroom or studio conversion.
ADU Cost & ROI Estimator
Estimate your investment and potential rental income before you commit to anything.
ADU Cost & ROI Estimator
Estimates for Central Valley, CA — actual cost varies by project
* Estimates based on Central Valley averages. Actual cost depends on site conditions, finishes, and permits. Request a free estimate for an accurate quote.
How Our ADU Process Works
From your first call to the final inspection — here's exactly what to expect when you hire C Hernandez Construction for your ADU.
Free Consultation
We visit your property, review your goals and budget, and answer every question — no cost, no pressure.
Design & Planning
We help coordinate plans and site drawings. We work with your designer or can refer you to trusted local drafters.
Permit Submission
We assist with submitting to your city's building department. California AB 2221 has streamlined ADU permits significantly.
Foundation & Framing
Our licensed crew breaks ground, pours the foundation and frames the structure — the phase we specialize in.
MEP Rough-In
Electrical, plumbing and mechanical rough-in with licensed subcontractors we coordinate directly.
Finish & Final Inspection
Drywall, paint, flooring, trim and fixtures. City final inspection passed and your ADU is ready to occupy or rent.
Get Your Free ADU Estimate
Tell us about your project and we'll get back to you the same day with a free, no-obligation estimate.
ADU Built by Our Crew
ADU Framing in the Bay Area
ADU FAQ
How long does it take to build an ADU?
From permit approval to completion, an ADU typically takes 4–8 months depending on type and size. We can help estimate your specific timeline during the free consultation.
Can an ADU be rented out?
Yes. ADUs can be rented as long-term rentals under California law. Short-term rental rules vary by city — check with your local municipality.
Do you handle ADU permits?
We assist with permit coordination and work closely with your local building department throughout the process. We've navigated permits in Ceres, Modesto, Turlock, and across Stanislaus County.
What cities do you build ADUs in?
We build ADUs in Ceres, Modesto, Turlock, Salida, Riverbank, Patterson and surrounding Central Valley communities.
What is the minimum size for an ADU?
California law allows ADUs as small as 150 sq ft, but most practical ADUs are 400–1,200 sq ft. Use the estimator above to see costs for your desired size.
Do ADUs increase home value?
Yes — significantly. A permitted ADU typically adds more value than it costs to build, especially in the Central Valley rental market where demand is high.
Why Licensed Matters for ADUs
An unpermitted ADU cannot be legally rented, financed, or sold. Hire licensed — protect your investment.
| Factor | C Hernandez Construction Lic. #1106454 | Unlicensed Contractor |
|---|---|---|
| CA State License Verified | ||
| Liability Insurance | ||
| Workers' Compensation | ||
| Pulls Required Permits | ||
| Passes City Inspections | ||
| Protects Your Home Value | ||
| Legal for Sale/Refinance | ||
| Accountable if Issues Arise |
In California, hiring an unlicensed contractor for projects over $500 is illegal and can void your homeowner's insurance.
ADU Construction in the Central Valley
We serve the entire Stanislaus County area and surrounding communities. Same licensed crew, same quality — wherever you are.
Our home base. We know the local permit office and inspection requirements inside and out.
Serving all Modesto neighborhoods — from East Side to West Side and surrounding areas.
ADUs, framing, and home additions throughout Turlock and nearby communities.
Fast service to Salida with the same licensed, inspected quality as everywhere we build.
Experienced with Riverbank building codes and permit processes for residential projects.
Serving Patterson with framing, ADU construction, and general contracting services.
Recent Projects
Real projects from our crew — framing, ADUs, additions and more across the Central Valley.
Ready to Start Your ADU?
Call us or request a free estimate. We're available Mon–Sat 7am–6pm.