ADU Regulations in San Bernardino, California
Everything you need to know about building an ADU in San Bernardino — size limits, setbacks, permits, and costs.
How many ADUs are allowed in San Bernardino?
- → 1 Detached ADU (up to 1,200 sq ft)
- → 1 Attached ADU
- → 1 Junior ADU / JADU (up to 500 sq ft)
- → Up to 8 detached ADUs
- → Interior conversions up to 25% of existing units
All California cities must follow state-law minimums. San Bernardino follows California AB 68 and subsequent ADU laws.
San Bernardino ADU rules & limits.
| ADUs Allowed | Up to 3 units on a single-family lot (primary home + 1 ADU + 1 JADU); up to 8 detached ADUs on multifamily lots |
|---|---|
| Max ADU Size | 1,200 sq ft |
| Setbacks | 4 ft side & rear (CA state baseline) |
| Height | 16 ft detached, 18 ft permitted near transit corridors |
| Parking | Not required in most cases; no replacement parking for garage conversions |
| JADU Allowed | Yes — up to 500 sq ft; owner-occupancy required if JADU is present |
| Impact Fees | Waived under 750 sq ft (state law) |
| Permit Timeline | 60 days maximum (state-mandated review window) |
San Bernardino is one of the most ADU-friendly cities in the region — low impact fees, expanded height allowances near transit, and an active push from the city to grow housing supply.
Contact: San Bernardino Building & Safety: (909) 384-5057
What could your San Bernardino ADU earn?
Rental estimates based on current Inland Empire market rates. Actual rents vary by condition, amenities, and local demand.
Four paths to an ADU in San Bernardino.
From idea to reveal.
Free Feasibility Consultation
We walk your lot, check setbacks and lot coverage, and confirm what your jurisdiction will approve.
Design & Engineering
Floor plan, elevations, structural calcs, and Title 24 energy compliance — drawn for your specific lot.
Permit Submission & Approval
We submit to your city or county, manage plan-check corrections, and pay the permit fees.
Construction
Same Construction Station crew handles foundation, framing, MEP, drywall, and finish — start to keys.
Final Inspection & Move-In Ready
Final city inspection, certificate of occupancy where applicable, and two-year workmanship warranty.
Why build an ADU in San Bernardino.
San Bernardino offers the lowest barrier to entry for ADU construction in the eastern Inland Empire. Impact fees are among the lowest in the region, lot sizes on the Westside, North End, and Verdemont are larger than the regional median, and home values have appreciated substantially over the past five years — meaning ADU appraisal lift is real. The expanded 18 ft height allowance near transit corridors is meaningful for homeowners within a half-mile of the Metrolink station or sbX bus rapid transit, where a true two-story detached ADU becomes feasible on lots that would only support single-story elsewhere. Rental demand is steady from Cal State San Bernardino students, San Manuel Casino employees, county government workers, and Loma Linda commuters — and San Bernardino does not enforce additional short-term rental restrictions beyond the state's 30-day minimum.
Ready to build an ADU in San Bernardino?
We’ll walk your lot, confirm what San Bernardino will allow, and ballpark cost before you commit to anything.
San Bernardino ADU questions, answered.
How much does an ADU cost in San Bernardino?
How long does it take to get an ADU permit in San Bernardino?
Can I rent my ADU in San Bernardino?
Do I need owner-occupancy for an ADU in San Bernardino?
Does Construction Station build ADUs in San Bernardino?
ADU regulations change frequently. Always verify current requirements with the San Bernardino Planning Department at (909) 384-5057. This page was last updated May 2026.