California ADU rules · Siskiyou County
Can I Build an ADU in Yreka?
Yes — you can build an ADU in Yreka. California's statewide ADU law requires every city, including Yreka, to approve a qualifying accessory dwelling unit by right, plus a junior ADU (JADU) on a single-family lot. What varies city to city are the local specifics below.
Can you build one?
ADUs allowed
CA state lawYes — by right
ADUs and JADUs are allowed by right in all residential and mixed-use zones; ministerial approval, no hearing.
Units on a single-family lot
Local rule1 ADU (conversion), 1 detached ADU (new), 1 JADU — all may be allowed if criteria met
Allows both a conversion ADU and a new detached ADU plus a JADU on a single lot if criteria are met.
Units on a multifamily lot
Local ruleConversions (>=1 or 25% of units), up to 8 detached (not to exceed number of existing units); up to 2 detached on lot with proposed multifamily dwelling
Detached ADUs on multifamily lots capped at 8 or number of existing units; up to 2 detached on proposed multifamily lots.
Junior ADU (JADU)
Local ruleAllowed
JADUs allowed only in R-1 zones.
Size & height
Max detached ADU size
Local rule1,200 sq ft
Local maximum for detached ADUs is 1,200 sq ft.
Max attached ADU size
Local rule50% of primary dwelling, >=800 sq ft, max 1,200 sq ft
Attached ADUs capped at 50% of primary, but at least 800 sq ft and no more than 1,200 sq ft.
Guaranteed minimum size
CA state law800 sq ft
An 800 sq ft ADU must be allowed regardless of FAR/lot-coverage caps; a city also cannot cap an attached ADU below 850 sq ft (1,000 for 2+ bedrooms).
Max JADU size
CA state law500 sq ft
Max height
CA state law16 ft
16 ft baseline; cities must allow 18 ft within ½ mi of a major transit stop or where the primary dwelling is two-story, and 20 ft on a lot with a multistory multifamily building.
Setbacks
Side setback
Local rule4 ft
4 ft side setback required for new construction; conversions exempt.
Rear setback
Local rule4 ft
4 ft rear setback required for new construction; conversions exempt.
Front setback
CA state lawNo front setback may block the mandatory 800 sq ft / 16-ft / 4-ft-setback ADU; otherwise per base zone
Separation from main house
CA state lawNone required
No statewide separation requirement between the ADU and the primary dwelling.
Parking
Parking required
Local ruleUp to 1 space
Max 1 space per unit or per bedroom (whichever is less); no new/additional parking for JADUs.
Transit parking exemption
CA state lawYes — no parking required near transit & for conversions
No parking may be required within ½ mi walking distance of transit, in a historic district, for an ADU within an existing structure, within one block of car-share, or in certain permit-parking areas.
Garage-conversion replacement parking
Local ruleNot required
No replacement parking required for garage/carport conversions.
Approval, timeline & cost
Approval path
CA state lawMinisterial (by right)
No public hearing or discretionary design review for a qualifying ADU.
Approval timeline
CA state law60 days
The agency must act within 60 days of a complete application — and the ADU is deemed approved if it does not.
Owner-occupancy
Local ruleOnly for a JADU
Owner-occupancy required for JADUs only; not required for ADUs.
Impact-fee waiver
CA state lawWaived under 750 sq ft
An ADU of 750 sq ft or less pays no impact fees (the 750 sq ft threshold itself is exempt under § 66311.5); larger ADUs pay fees proportional to the primary dwelling. JADUs (≤ 500 sq ft) are exempt.
Permits required
Local ruleBuilding permit
No use permit or discretionary review required.
Yreka-specific factors that can change the answer
State law sets the floor, but these local conditions often decide whether a specific parcel works.
Very High Fire Hazard Severity Zone (VHFHSZ)
No sprinklers required for ADUs unless primary dwelling requires them; other fire protection may be required if setbacks are not met.
Historic District
Parking exemptions apply for ADUs/JADUs in historic districts.
Yreka allows both a conversion and a new detached ADU plus a JADU on a single-family lot if criteria are met, and sets a 1,200 sq ft local maximum for both attached and detached ADUs. JADUs are only allowed in R-1 zones. No replacement parking is required for garage conversions.
Frequently asked questions
Can I build an ADU in Yreka?
Yes. California's statewide ADU law requires Yreka to approve a qualifying accessory dwelling unit ministerial (by right), plus a junior ADU (JADU) on a single-family lot.
How big can an ADU be in Yreka?
A detached ADU of at least 1,200 sq ft must be allowed, and an ADU of 800 sq ft can never be zoned out by floor-area or lot-coverage limits. A JADU can be up to 500 sq ft.
What are the setback requirements for an ADU in Yreka?
Side and rear setbacks are limited to 4 ft. No front setback may block the mandatory 800 sq ft / 16-ft / 4-ft-setback ADU; otherwise per base zone.
Is parking required for an ADU in Yreka?
Up to 1 space. No parking can be required within ½ mile of transit, for conversions, or for units inside the primary home. When a garage is converted, replacement parking is not required.
How long does ADU approval take in Yreka?
A complete application must be acted on within 60 days, with ministerial (by right) — no public hearing or discretionary design review for a qualifying ADU.
Do I have to live on the property to build an ADU in Yreka?
Owner-occupancy: only for a jadu. ADUs under 750 sq ft are also exempt from impact fees.
Sources
- Yreka Municipal Code § 16.46.170 (Ord. No. 887, § 3, 12-16-2025)
- Yreka Municipal Code § 16.46.170(T)
- Yreka Municipal Code § 16.46.170(U)
- Yreka Municipal Code § 16.46.170(A), § 16.12.045
- Yreka Municipal Code § 16.46.170(A)
- Yreka Municipal Code § 16.46.170(H)
- Yreka Municipal Code § 16.46.170(J)
- Yreka Municipal Code § 16.46.170(L), (O)
- Yreka Municipal Code § 16.46.170(E)
- Yreka Municipal Code § 16.46.170(S)
- Yreka Municipal Code § 16.46.170(P)
- Cal. Gov. Code §§ 66310–66342 (ADU Law)
- HCD 2025 Accessory Dwelling Unit Handbook
- Cal. Gov. Code § 66317 (ministerial approval, 60-day deadline)
- Cal. Gov. Code § 66321 (size minimums & height)
- Cal. Gov. Code § 66333 (junior ADUs)
- Cal. Gov. Code § 66323 (by-right ADU/JADU, 800 sq ft, 4-ft setbacks)
- Cal. Gov. Code § 66322 (ADU parking; § 66334 covers JADU parking)
- Cal. Gov. Code § 66311.5 (impact fees: none for an ADU ≤ 750 sq ft or JADU ≤ 500 sq ft)
Last updated 2026-06-25. This is an AI-assisted summary of Yreka's ADU rules, drawn from its published ordinance and California ADU law — general information, not legal advice, and it may be incomplete or out of date. Verify the controlling rule for your specific parcel with Yreka Planning before relying on it.
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