Cost & ROI calculator
ADU cost calculator
This free ADU cost calculator estimates your Sacramento-region build in seconds. Pick a type, drag the size, and choose your city to see a 2026 turnkey cost range, the financed monthly payment, projected rent, and roughly how fast it pays back. No email required.
Estimate your ADU
Ballpark 2026 turnkey cost, financing, and rental return for your area.
Estimated turnkey cost
$250–$360 / sq ft · incl. design, permits & construction
Estimates only — 2026 regional ranges, not a bid. Your real price depends on site conditions, finishes, and your lot. We confirm with a free feasibility check.
Want the static numbers instead of a personalized estimate? See our full published ADU pricing →
How it works
Three inputs, one number
The calculator takes three things and turns them into a real-world estimate. Here's what each one does.
ADU type
Detached, garage conversion, attached, junior, or multigenerational. Each type carries its own cost-per-square-foot band — a garage conversion reuses an existing slab and runs far cheaper per foot than a ground-up detached build.
Size
Square footage drives the total. The slider is capped to the realistic range for the type you picked, and the estimate flags the 750 sq ft line where impact fees disappear.
City
Your submarket sets a cost multiplier. Sacramento and Elk Grove sit at baseline; Roseville, Folsom, Granite Bay, and El Dorado Hills run 6–12% higher on both build cost and achievable rent.
What you get
Four answers, not just a price
Most calculators stop at a cost. This one frames the whole decision — what it costs, what it earns, and how the two compare.
Turnkey cost range
A low-to-high all-in band, plus the implied $/sq ft. Turnkey means design, engineering, permits and city fees, site work, construction, and finishes — not a stripped shell number.
Estimated financed payment
What that build costs per month if financed over 30 years near current rates — the figure that actually matters when you weigh it against rent.
Projected monthly rent
An observed 2026 Sacramento-area rent band for that size and submarket, roughly $1,000–$2,800/month.
Payback period
Roughly how many years of rent it takes to cover the build — a quick gut-check on the investment, not a formal pro forma.
What's in the number
What the estimate covers
The cost the calculator shows is a turnkey figure. That word is doing a lot of work — here's exactly what's inside it, and the site-specific costs that can sit outside it.
Included in the estimate
- Architectural design & structural engineering
- Title 24 energy compliance
- Permits and city/jurisdiction fees
- Site prep, foundation, and utility connections
- Full construction — framing through finishes
- Cabinets, counters, flooring, fixtures, and appliances
Priced after we see your lot
- Major lot grading or retaining walls on steep sites
- Long utility trenching runs (deep-lot detached builds)
- Solar beyond the code-required minimum
- Landscaping, fencing, and hardscape beyond the unit
- Sewer or panel upgrades a specific property may need
The same five cost buckets, broken out line by line, live on the pricing page. For market-wide ranges and the factors behind them, read how much an ADU costs in Sacramento.
How accurate it is
A ballpark, not a bid
This calculator is built to land you in the right range so you can plan and compare — it is not a fixed quote. It applies 2026 Sacramento-region cost-per-square-foot bands and a per-city multiplier, then assumes mid-range finishes and a standard, buildable lot. Three things move your real number that a calculator can't see.
Your lot
Soil, slope, access, tree removal, and how far utilities have to travel can swing the total by tens of thousands either way.
Your finishes
The slider assumes mid-range. Builder-basic trims the cost; quartz, custom cabinetry, and premium fixtures push toward the top of each band.
Your jurisdiction
City fees and plan-check timelines vary. Units under 750 sq ft skip impact fees; pre-approved plans can cut permitting to about 30 days.
We build on a $1,000 deposit — the most California law lets a contractor collect up front — and the rest is tied to inspection-verified milestone draws, so you never pay ahead of completed, permitted work. A free feasibility check turns this estimate into a firm, lot-specific quote.
From estimate to plan
Once you have a number
Use the figure above as your starting point, then dig into whichever question it raised.
See full pricing
Published ranges by ADU type, what a turnkey price includes, and the $1,000-down milestone payment schedule.
View ADU pricing →Finance the build
HELOC, cash-out refi, renovation and construction loans — and why the financed payment often runs below the rent. (CalHFA grant is exhausted.)
Explore ADU financing →Browse models
Prefer a fixed-price floor plan? Our model lineup shows sizes, beds, baths, and locked-in pricing per design.
See ADU models →ADU cost calculator FAQs
It uses 2026 Sacramento-region cost-per-square-foot ranges adjusted for your city, so it's a realistic ballpark — not a bid. Your exact price depends on site conditions, finishes, and your lot, which we confirm in a free feasibility check.
Yes. The figures are turnkey — they include design, engineering, permits and city fees, site work, construction, and finishes. They do not include site-specific surprises like deep utility trenching or major grading, which we price after seeing your lot.
Each Sacramento-area submarket carries a cost multiplier. Sacramento and Elk Grove are baseline; Roseville, Folsom, Granite Bay, and El Dorado Hills run 6–12% higher on labor and materials — and usually support higher rents that offset the added cost.
From observed 2026 Sacramento-area ADU rents by size and submarket, roughly $1,000–$2,800/month. A sub-400 sq ft unit lands near the bottom; an 800-plus sq ft two-bedroom in a premium area lands near the top.
No. The calculator personalizes a number to your inputs. Our full published price ranges, what's-included tables, and the $1,000-down payment schedule live on the pricing page — this tool links you straight there.
No. The calculator runs entirely in your browser with no form gate. You only share contact details if you choose to request an exact, lot-specific quote.
Turn your estimate into a firm number
A free feasibility check confirms what's buildable on your lot and gives you an exact, all-in quote — usually within a few days.