As of October 2026, the City of Bakersfield's own ADU program offers a rough planning figure of $150 to $300 per square foot, with whole projects running from about $30,000 for a simple interior junior ADU to $400,000 or more for a large detached unit on a difficult lot. Fees, utility work and finishes move the final total.
What does that look like at common ADU sizes?
The table simply multiplies the city's rough $150 to $300 per sq ft placeholder by typical unit sizes. It is arithmetic for orientation, not a quote and not our pricing.
| Unit size | At $150 per sq ft | At $300 per sq ft | Typical fit |
|---|---|---|---|
| 400 sq ft | $60,000 | $120,000 | Studio, junior ADU or small garage conversion |
| 600 sq ft | $90,000 | $180,000 | One-bedroom |
| 850 sq ft | $127,500 | $255,000 | Largest one-bedroom under the city's detached limit |
| 1,200 sq ft | $180,000 | $360,000 | Two-bedroom detached ADU at the city maximum |
Per-square-foot figures can mislead on small units. The city's FAQ points out that a small ADU costs nearly as much per project as a larger one, because the kitchen and bathroom drive so much of the price. It puts a kitchen at roughly $25,000 to $50,000 and each bathroom at $15,000 to $25,000.
Which ADU type costs least in Bakersfield?
According to the city's ADU FAQ, interior conversions are usually the cheapest and new construction the most expensive. Factory-built units can save time, but the FAQ notes their total cost often lands close to site-built. A sound garage or spare wing of the house is the strongest starting point for a lower budget.
What permit and impact fees apply?
- Inside city limits: as of October 2026, the city charges a planning application fee based on project valuation and square footage, a separate building permit fee, and school fees for ADUs of 500 sq ft or more.
- Unincorporated Kern County (including Oildale): Kern County Public Works lists approximate fees of about $1.00 per sq ft for building, about $700 for planning plus $52 for an address, and about $4.00 per sq ft in school fees. Traffic and park fees apply only above 750 sq ft. Its worked example puts a 400 sq ft ADU at about $1,336.51 before school and sewer fees.
- State impact fee rule: as of October 2026, ADUs of 750 sq ft or less and junior ADUs of 500 sq ft or less are exempt from impact fees.
What else should a Bakersfield budget include?
- Design and engineering, unless you start from one of the city's standard or pre-reviewed plans.
- Utilities. PG&E serves electricity, while water service depends on the address; the city points owners to its City Services Lookup tool to find the provider. New or separate connections may be needed for an ADU, though generally not for a junior ADU.
- Cooling. Valley summers make insulation, shading and properly sized air conditioning a real line item.
- Solar on a newly built detached unit, required under the California Energy Code as of October 2026, with exceptions.
Why do Bakersfield quotes vary so much?
Mostly because of what is included. Ask each builder for a written, itemized quote that spells out design, fees, how far utility work runs, cooling equipment, finish allowances and who pays for plan-check corrections. That makes two quotes comparable.
How do I get a figure for my property?
Use the lot check form. We confirm the rules that apply, visit the property and then send a written, itemized quote. The city also hosts an online ADU calculator for rough early estimates. Next, read what an ADU rents for in Bakersfield.
Sources, as of October 2026:
- City of Bakersfield ADU program, ADU frequently asked questions (bakersfieldadu.us; undated, accessed October 2026).
- City of Bakersfield Planning Division, ADU and JADU how-to page (undated, accessed October 2026).
- Kern County Public Works, Building Inspection: pre-approved ADU plan instructions for property owners and contractors, and Pre-Approved Accessory Dwelling Units page (accessed October 2026).
- California Department of Housing and Community Development, ADU Handbook (updated March 2026, with addendum on law effective January 1, 2026), hcd.ca.gov.