Garage / interior conversion ADU
$170 – $230 / sqft
Lowest entry point. Works when the existing slab, walls, and panel can stay.
2026 California pricing
ADU pricing, no games.
Here is what California ADUs and remodels actually cost in 2026. The bands below come straight from our own close-out books — not industry averages. Most projects we deliver land in the lower half.
JADU inside the main house
$160 – $220 / sqft
Up to 500 sqft. Often the cheapest path to a permitted unit.
Detached new-build ADU
$220 – $290 / sqft
Freestanding unit in the rear yard with its own kitchen and bath.
Attached ADU / small addition
$210 – $280 / sqft
Bumps off the main house. Ties into existing structure and utilities.
Kitchen remodel
$215 – $325 / sqft
Cabinets, counters, lighting, full MEP refresh.
Bath remodel
$235 – $345 / sqft
Full gut: tile, fixtures, waterproofing, plumbing rough-in.
The real number
Want a fixed price for your lot?
Free 45-minute site walk. We measure the lot, check the panel and sewer, then email a written, line-by-line quote within a week. No pressure, no obligation.
Book the free site walkWhat's included
- Foundation, framing, roof, exterior — turnkey shell.
- Full MEP: electrical, plumbing, HVAC mini-split.
- Standard finishes: cabinetry, tile, fixtures, paint.
- Permit drawings, plan check, all inspections.
What sits on top
- Designer upgrades — premium tile, custom millwork.
- Hillside, fire-zone, or coastal jurisdiction soft costs.
- Long utility runs (LADWP / PG&E pole pulls).
- Appliances and FF&E above standard spec.
We surface every one of these on the site walk — before you sign.
FAQ
Pricing FAQ
How accurate is the ADU cost calculator?
Within ±15% for typical projects on flat lots with standard utility access. The estimator is based on our last 80 California ADU contracts, segmented by region, type, and finish level. Unusual lots (steep slope, deep setbacks, problematic soil) need a site walk to confirm.
What's not included in the calculator number?
Property tax impact (~1.1% of constructed value annually), permit fees (city-specific, $8K–$40K typically — see the permit directory), utility hookup fees (PG&E / SCE / SoCalGas / SFPUC), soft costs like landscape and driveway, and FF&E (furniture). The calculator covers hard construction cost only.
Why is my number higher than a calculator I saw on another site?
Most ADU calculators online use 2020–2022 cost data and skip Title 24 envelope upgrades, panel upgrades, and sewer-lateral compliance. Our 2026 numbers include them — see the full 2026 California cost report. The most common surprise on lowball quotes is the missing $15K–$45K in code-driven scope.
Can I get financing for an ADU and add the cost to my mortgage?
Yes — Fannie Mae ADU appraisal rules let you refinance against the post-construction value. Full breakdown in ADU financing in California (2026) and HELOC vs. RenoFi vs. construction loan. We don’t take referral fees.
Does the calculator account for solar and battery?
Yes — solar PV is included in the line item because Title 24 requires it in most California climate zones. Battery storage is optional and added as a separate line. Both are at-cost; we don’t mark up energy systems.
What if I want luxury finishes vs. standard?
The calculator has three finish tiers: 'rental-grade' (durable, sub-$50/sqft tile, base cabinets), 'mid-market' (custom paint-grade cabinets, $75–$120/sqft tile), and 'high-end' (custom wood cabinets, slab counters, $150+/sqft tile, premium appliances). Tier choice swings cost by ±$60K on a typical 800-sqft ADU.
How long is my calculator estimate valid for?
60 days — California construction costs are moving roughly 5–8% per year. After 60 days, re-run with current numbers or request a written estimate.
Do you share my calculator results with anyone?
No. Results are local to your browser unless you choose to email them to yourself or request a follow-up. We never sell or share inputs.
Calculator outputOff-site · Leo replies tonight
Numbers look right? Get the same scope priced by a real PM.
- Same line items the calculator used, plus the ones it missed
- Signed, dated estimate — not a screenshot
- Turnaround: 48 hours
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