California ADU rules · Marin County
Can I Build an ADU in Novato?
Yes — you can build an ADU in Novato. California's statewide ADU law requires every city, including Novato, 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
CA state law1 ADU + 1 JADU
At least one ADU and one JADU per single-family lot (a conversion ADU may also be possible).
Units on a multifamily lot
Local ruleconversions (>=1 or 25% of units) + up to 2 detached (or up to 8 detached, not to exceed number of existing units, for existing multifamily buildings)
Novato allows up to 2 detached ADUs by default, but up to 8 detached ADUs are allowed for existing multifamily buildings, not to exceed the number of existing units.
Junior ADU (JADU)
CA state lawAllowed
Up to 500 sq ft, within the walls of an existing single-family home (single-family lots only).
Size & height
Max detached ADU size
Local rule1,000 sq ft
Detached ADUs are capped at 850 sq ft (studio/1-bed) or 1,000 sq ft (2+ beds), but at least 800 sq ft must be allowed by-right.
Max attached ADU size
Local rule50% of primary, up to 850 (studio/1-bed) or 1,000 (2+ beds), >=800 by-right
Attached ADUs are capped at 50% of the primary dwelling, up to 850/1,000 sq ft, but at least 800 sq ft must be allowed by-right.
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
Local rule16 ft
Detached ADU: 16 ft standard; 18 ft if within ½ mile of major transit; up to 20 ft to match primary roof pitch. Attached ADU: up to 25 ft or zone limit, max 2 stories.
Setbacks
Side setback
CA state law4 ft
A city cannot require more than 4 ft side or rear setback; conversions of existing structures are exempt.
Rear setback
CA state law4 ft
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
Local rule3 ft
Detached ADUs must be at least 3 ft from any other building on the lot.
Parking
Parking required
Local ruleUp to 1 space
No more than 1 space per unit or bedroom (whichever is less) for ADUs; JADUs require no parking.
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 ADU garage/carport conversions; JADUs require replacement parking on-site.
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 only for JADUs (owner must occupy either the primary or the JADU).
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
CA state lawBuilding permit
Only a ministerial building permit — no conditional use permit or discretionary design review for a qualifying ADU.
Novato-specific factors that can change the answer
State law sets the floor, but these local conditions often decide whether a specific parcel works.
Historic/HPOZ
Courtesy notice required for JADUs; demolition of garages in historic districts may require notice.
Novato caps detached and attached ADUs at 850/1,000 sq ft (studio/1-bed or 2+ beds), but must allow at least 800 sq ft by-right. Up to 8 detached ADUs may be allowed on large multifamily lots, and a 3 ft separation is required between detached ADUs and other buildings.
Frequently asked questions
Can I build an ADU in Novato?
Yes. California's statewide ADU law requires Novato 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 Novato?
A detached ADU of at least 1,000 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 Novato?
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 Novato?
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 Novato?
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 Novato?
Owner-occupancy: only for a jadu. ADUs under 750 sq ft are also exempt from impact fees.
Sources
- NMC §19.34.030 (ADUs), §19.34.031 (JADUs), Ord. No. 1721, § 4(Exh. A), 1-28-2025
- NMC §19.34.030.N.2.c, d
- NMC §19.34.030.N.1.b(1); NMC §19.34.030.N.2.a(1); NMC §19.34.030.N.2.c
- NMC §19.34.030.N.1.a(1); NMC §19.34.030.N.2.c
- NMC §19.34.030.N.2.a(4); NMC §19.34.030.N.2.c
- NMC §19.34.030.N.1.b(5)
- NMC §19.34.030.N.1.e; NMC §19.34.031.P
- NMC §19.34.030.N.1.f; NMC §19.34.031.Q
- NMC §19.34.031.K
- NMC §19.34.031.R
- 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 § 66323 (by-right ADU/JADU, 800 sq ft, 4-ft setbacks)
- Cal. Gov. Code § 66333 (junior ADUs)
- Cal. Gov. Code § 66321 (size minimums & height)
- 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 Novato'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 Novato Planning before relying on it.
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