Everything homeowners ask about building an ADU in Sacramento — answered with 2026 data.
Yes, ADUs are allowed in Any lot in a zone that lists 'Dwelling unit, accessory' and 'Dwelling unit, junior accessory' as accessory uses, which includes the R-1 and R-2 residential zones (SCC 17.204.210(C), 17.204.510(C)), provided the lot already has, or is concurrently building, a single-unit, duplex or multi-unit dwelling (17.228.105(B)(2)(a)(i)); under the state option, any residential or mixed-use zone (17.228.105(C)(1)). Exceptions: no ADUs in the Executive Airport clear zone EA-1, and only one ADU or JADU per lot in the EA-2 and EA-3 approach zones (17.312.060). In a historic district or on a landmark property a local-option ADU must also meet the city's ADU Design Standards for Historic Properties (17.228.105(B)(2)(c)(vi)). Check your zone and overlays in the city's Land Information Lookup App in Sacramento, CA. The maximum size for a detached ADU is Local option: 1,200 sq ft for one detached ADU; with two detached ADUs their combined floor area may not exceed 1,200 sq ft, for example 400 + 800 (17.228.105(B)(2)(b)(iii)). Floor area counts everything inside the ADU's building envelope except garages and accessory structures. State option: 800 sq ft for a new detached unit (17.228.105(C)(1)(b)). Attached ADUs can be up to Local option: the greater of 50% of the primary dwelling's existing floor area, or 850 sq ft for a studio or one-bedroom, or 1,000 sq ft with two or more bedrooms. Sacramento has an ADU-friendliness score of 9/10. Check our full Sacramento ADU rules page for complete zoning details.
ADU construction in Sacramento typically costs $170,000-$400,000. The cost per square foot averages $250-$500. Garage conversions are more affordable at $90,000-$200,000, while prefab ADUs cost $170,000-$340,000. Permit fees add City fee estimate form CDD-0419 (rev. 7/12/2026), at a $170.80 per sq ft valuation: about $5,272 total for a 749 sq ft new detached ADU, $10,624 at 750 sq ft and $14,843 at 1,200 sq ft. Line items at 1,200 sq ft: building permit $1,790.36, plan review $751.95, fire administrative $176, fire inspection $294 ($0.11 per sq ft, $294 minimum), fire plan review $260, planning inspection $526, planning review $263, public works and utilities review $205 deposit each plus hourly, construction excise tax $945.60, general plan fee $533 ($2.60 per $1,000 of valuation), residential construction tax $315, technology fee $254.23. Not included: school district fees (paid to the district, form CDD-0226), regional sanitation and county sewer fees, and any water or sewer tap, housing or project-area impact fees. Optional ADU Zoning Review: $0 (was $117 before July 2026). Optional written fee estimate: $164 (form CDD-0278). Extra review time bills at $216 per hour for Building and $263 per hour for Planning to your budget. See our detailed Sacramento ADU cost guide.
Detached ADUs in Sacramento can be up to Local option: 1,200 sq ft for one detached ADU; with two detached ADUs their combined floor area may not exceed 1,200 sq ft, for example 400 + 800. Attached ADUs are limited to Local option: the greater of 50% of the primary dwelling's existing floor area, or 850 sq ft for a studio or one-bedroom, or 1,000 sq ft with two or more bedrooms. Junior ADUs (JADUs) have a cap of 500 sq ft, inside the walls of a single-unit dwelling including an attached garage, with its own outside entrance and an efficiency kitchen with a cooking appliance, counter and cabinets. A JADU without its own bathroom must also keep an interior door to the main house. A deed restriction barring separate sale must be recorded before final inspection (17.228.105(B)(3)). Maximum height is Local option: the height limit of the lot's zone applies to the ADU, which is 35 ft in R-1 and R-2 (17.228.105(B)(2)(c)(ii); 17.204.220(A), 17.204.520(A)). State option: 18 ft, or 20 ft where extra height is needed to match the roof pitch of the main house (17.228.105(C)(1)(b)). In a historic district or on a landmark lot a detached ADU may not be more than 150% of the height of the contributing building on the same or an adjoining parcel (ADU Design Standards for Historic Properties, Standard 2.1). You are allowed up to Local option on a qualifying lot.
Rear setback: 3 ft or none under the local option: no rear setback is required for a single-story ADU, or the first floor of a two-story ADU, when the whole unit is more than 60 ft from the front property line; if any part is within 60 ft of the front property line, or for a second floor, the zone's rear setback or 3 ft applies, whichever is less, so 3 ft in R-1 and R-2 (17.228.105(B)(2)(c)(iii)). No setback for an existing structure converted or rebuilt to the same footprint. No ADU may sit inside the 20-ft setback from the landside toe of a levee (17.204.240(E)). State option: 4 ft (17.228.105(C)). Side setback: 3 ft or none for the interior side under the local option, the same rule as the rear: no setback for a single-story unit or first floor more than 60 ft from the front property line, otherwise the zone's setback or 3 ft, whichever is less; the R-1 interior side setback is 5 ft (3 ft on lots under 52 ft wide), so 3 ft governs (17.228.105(B)(2)(c)(iii); 17.204.240(B)). Street side on a corner lot: the zone's full street side setback, 12.5 ft in R-1 and R-2 (17.204.240(C), 17.204.540(C)). Detached ADUs must be at least 4 ft from the main house and from each other (17.228.105(B)(2)(c)(i)). State option: 4 ft side setbacks. Front setback: Local option: the zone's front setback applies to any part of an ADU within 60 ft of the front property line. In R-1 and R-2 that setback matches the two nearest houses on the same side of the block, or 20 ft if there is no other building on that block face (17.204.240(A), 17.204.540(A)). One ADU of 800 sq ft or less may be built inside the front setback when the rear and side yards cannot fit a two-story detached ADU of at least 800 sq ft or an attached ADU of at least 800 sq ft (17.228.105(B)(2)(c)(iii)(4)). State option: no zoning standard other than 17.228.105(C) applies to a qualifying unit (17.228.105(C)(3)). Note that garage conversions may be exempt from setback requirements if the existing structure is already within the setback area.
None. Sacramento sets no minimum off-street vehicle parking for any land use (SCC 17.608.030(B)), and when a garage, carport or driveway space is removed to build an ADU or JADU no replacement parking is required for the ADU or for the other homes on the lot (17.608.020(K)). Many cities and states have been relaxing ADU parking requirements in recent years. In California, no additional parking is required for ADUs near transit.
Not required for an ADU. For a JADU the city code still requires the property owner to live on site unless the owner is a government agency, land trust or housing organization (17.228.105(B)(3)(b)); state law since January 1, 2026 (Gov. Code 66333(b), AB 1154) allows that requirement only when the JADU shares a bathroom with the main house, so a JADU with its own bathroom should not need owner-occupancy. Confirm with the Planning Division before relying on either reading. Note that owner-occupancy rules vary by state law — California and several other states have eliminated this requirement for standard ADUs.
The ADU permit review timeline in Sacramento is typically 60 days by law: the city must approve or deny a complete application within 60 days when there is an existing home on the lot, or the ADU is deemed approved (17.228.105(B)(4)(b)-(c), matching SB 543). If the ADU is filed with a permit for a new house the city may wait until the house is approved, and any delay you request stops the clock. Published targets (ADU portal, Step 5): optional zoning review 1-3 weeks; building plan review roughly 1.5-2 months, with review cycle 1 at 20 business days, cycle 2 at 15 and cycle 3 at 5, not counting your time to answer corrections. State law gives a 30-day decision for an application that uses a city-preapproved plan or one identical to a plan approved in the current building-code cycle (Gov. Code 65852.27(b)); ask the Building Division whether a Shelf Ready plan qualifies. Plan check: Electronic Plan Check through the city's online permit portal. A detached ADU needs no fire sprinklers if the main house is unsprinklered and the ADU, excluding garage, is 1,200 sq ft or less; an attached ADU is exempt if the house is unsprinklered, the addition is no more than 50% of the original and the total stays under 3,600 sq ft. One water service per lot: the ADU ties into the house's water and sewer lines and normally needs no separate meter (City Code 13.04.070). Rooftop solar may be required under the California Energy Code; SMUD offers a free service consultation (CDD-0423, CDD-0009). Pre-approved plans availability: Yes, two programs. 1) Shelf Ready ADU Plans: three free city-designed detached plans, all-electric and built to the 2022 Residential Code, updated December 2025: studio 367 sq ft, one-bedroom 559 sq ft, two-bedroom 747 sq ft. Mirroring is allowed, other changes are not, and you supply the site plan. All three stay under the 750 sq ft impact-fee threshold. 2) AB 1332 Preapproved ADU Program for third-party detached plans (Gov. Code 65852.27): the process exists but the city's catalog listed no plans as of September 19, 2026. Either route still needs site-specific zoning and building review.
Average ADU rental income in Sacramento: 1-bedroom units rent for $1,500-$1,850/month, 2-bedroom units for $1,800-$2,250/month. Short-term rentals: Depends on which option the ADU was approved under. Expected ROI: 5-10% gross rental yield on a $250,000-$400,000 detached build renting at $1,800-$2,250/mo; a $90,000-$200,000 garage conversion at $1,500-$1,850/mo can gross 9-20% (estimates before taxes, vacancy and financing).
The minimum lot size for an ADU in Sacramento is No minimum lot size, width or depth for an ADU (17.228.105 sets none). The R-1 and R-2 minimums of 5,200 sq ft interior and 6,200 sq ft corner (17.204.230, 17.204.530) govern creating new lots, not adding an ADU. Under the local option an ADU covering less than 800 sq ft of the lot is exempt from the zone's lot-coverage cap of 40% or 2,500 sq ft (never over 50%) and from the open-space minimum (17.228.105(B)(2)(c)(ii); 17.204.220(C)). This applies to detached ADUs — garage conversions and JADUs may have different or no lot size requirements.
Garage conversions are one of the most popular and affordable ADU options. In Sacramento, a garage conversion typically costs $90,000-$200,000. The key advantages are lower cost (no foundation work), potential setback exemptions, and faster permitting. Read our complete garage conversion guide.
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