ADU Construction in Sacramento & the Greater Region
Detached ADUs, attached additions, garage conversions, and JADUs — designed, permitted, and built for rental income, resale value, and everyday livability.
ADU Types We Build
Three Ways to Add a Legal Second Unit
Whether you call it a granny flat, an in-law suite, a backyard cottage, or a casita, an accessory dwelling unit is one of the highest-leverage additions you can make to a Sacramento-region property — and the right type depends on your lot, your budget, and your goals.
Detached ADU
$175–$300 / sq ft
A brand-new standalone structure in the backyard — the most flexible option for maximizing rental income or creating a fully independent guest house, with its own entrance, utilities, and address.
Attached Addition
$100–$300 / sq ft
An addition connected to and expanding the main home — often the most cost-efficient path when you already have usable adjacent square footage and want to share a wall or utility run.
Garage Conversion
$25,000–$150,000
Convert an existing attached or detached garage into a rental unit, home office, or guest suite — typically the fastest and least expensive route to a permitted, income-producing ADU.
Our Process
From Feasibility to Final Inspection
We manage every phase of your ADU project so you're never coordinating architects, engineers, and inspectors yourself.
- 01
Feasibility Analysis
We assess your property, review Sacramento city and county zoning requirements, and determine the optimal ADU configuration for your lot, budget, and goals.
- 02
Design Coordination
Our team coordinates with architects and designers to create plans that maximize square footage, functionality, and rental appeal.
- 03
Engineering & Permitting
We handle structural engineering, permit applications, and regulatory compliance — including the differences between Sacramento County and City of Sacramento ADU rules.
- 04
Utility Coordination
Complete coordination of electrical, plumbing, HVAC, sewer, and other utility work so your ADU integrates cleanly with the existing property.
- 05
Expert Construction
Licensed, disciplined execution from our own crews and vetted trade partners — not a rotating cast of subcontractors.
- 06
Final Inspection & Delivery
Thorough quality checks and final inspections. Your ADU is finished, inspected, and ready for occupancy — our non-negotiable standard.
Faster Permitting
Build on a Sacramento Pre-Approved Plan
The City of Sacramento keeps a set of ADU plans that have already been reviewed and approved. Building from one of these means the design side of plan check is largely settled before you apply — you are no longer waiting on a reviewer to evaluate a brand-new design from scratch.
For an owner or investor, that usually translates into a shorter runway to permit and fewer correction cycles on the architectural set. You still handle a site-specific review — your lot, utilities, setbacks, and structural conditions — but you skip a large part of the design review that a fully custom ADU has to go through.
We are building one now: a 747 SF, 2-bed / 1-bath pre-approved unit, all-electric with rooftop solar and a heat pump water heater. See the build, excavation through stucco →
Sacramento Permitting Experience
We Know the Difference Between City and County Rules
Sacramento County and the City of Sacramento apply different setback, parking, and utility-connection rules to ADU permits — and El Dorado Hills, Granite Bay, Cameron Park, Folsom, and Rocklin each layer on their own jurisdictional quirks. We've built across all of them, so your permit application isn't a first attempt.
ADU as Rental Income
A well-placed ADU can add meaningful monthly rental income and long-term property value in the Sacramento market. We design and price every unit with that math in mind — not just square footage for its own sake.
See Investor Services →Get a Ballpark Number
Not ready for a full proposal? Run our free ADU Cost Estimator to get a tailored budget range for a detached ADU, attached addition, or garage conversion on your property.
Try the ADU Cost Estimator →Common Questions
ADU Basics Before You Call
How much does an ADU cost in Sacramento?
Garage conversions typically run roughly $25,000–$150,000, while detached ADUs typically run $105,000–$300,000, or about $175–$300 per square foot depending on finish level. Use our free ADU Cost Estimator for a number tailored to your project.
How long does permitting take?
Timelines vary by jurisdiction, lot condition, and utility scope. We walk every client through a realistic timeline during the feasibility phase — see our full FAQ page for more detail.
Verified Google Reviews
What Our Clients Say
We hired Folsom City Carpentry to build an ADU on our property in El Dorado Hills, and we couldn't be happier with the results. Hunter was professional, responsive, and easy to work with from start to finish. He explained the process clearly, stayed on schedule, and handled the project the right way with permits and inspections.
Hunter built a detached garage for us and handled the permits and inspections. He explained everything clearly so we understood why certain structural elements were needed.
Common Questions
ADU Questions We Get Every Week
How much does an ADU cost in Sacramento?
A detached ADU runs $175–$300 per square foot, an attached addition $100–$300, and a garage conversion typically $25,000–$150,000. A 747 sq ft detached unit we are building now came in at $149,500 including appliances, which works out to $200 per square foot. Finish level, lot conditions, and how far utilities have to run are what move the number.
How long does it take to build an ADU?
Plan on roughly nine to twelve months from first conversation to final sign-off, and understand that permitting — not construction — is usually the long pole. The shell of our current Sacramento ADU went from excavation to stucco in about nine weeks. Everything before and after that is design, plan check, corrections, and inspections.
Do I need a permit for an ADU in Sacramento?
Yes, always. Every ADU requires a building permit, and a garage conversion needs one too even though the structure already exists. Unpermitted work is the single most expensive mistake in this category — it surfaces at resale or refinance, and correcting it after the fact costs more than doing it right.
Can I build an ADU on my lot?
Usually, but the answer depends on your setbacks, lot coverage, existing utilities, and which jurisdiction you are in. State law has made ADUs much easier to approve in California, but local standards still control size and placement. We check this before you spend anything on plans.
What is a pre-approved ADU plan?
The City of Sacramento maintains a set of ADU designs that have already cleared architectural review. Building from one means the design portion of plan check is largely settled before you apply, which typically shortens the runway to permit and reduces correction cycles. You still go through a site-specific review for your particular lot.
Do you handle the permits, or do I?
We do. Structural engineering, permit applications, corrections, and inspection scheduling are all ours. You are not the one calling the county to find out why plan check went quiet.