ADU Builders in Rancho Cordova, CA (2026)

ADU builders in Rancho Cordova typically quote $155,000-$310,000 for a new detached unit, or about $250-$410 per square foot, including design, permitting, and construction. A garage conversion runs $80,000-$155,000 and a prefab/modular ADU averages $120,000-$255,000. Add city permit and plan-review fees (Confirm current building permit and plan check amounts with Rancho Cordova Building and Safety at (916) 851-8760 — the City publishes a Building Permit Fee Estimates tool rather than a flat ADU fee, and no ADU-specific fee schedule appears in its ADU material) plus impact fees of None at all below 750 sq ft. "No city-imposed impact fees shall be charged for an accessory dwelling unit that is less than 750 square feet in size. For accessory dwelling units 750 square feet or larger, city-imposed impact fees shall be charged proportionately in relation to the square footage of the primary dwelling" (City of Rancho Cordova ADU FAQ, Planning Department). That is the single largest cost lever on a Rancho Cordova ADU: a 749 sq ft unit and a 760 sq ft unit are not 11 square feet apart on the fee bill. School district and utility district fees are separate — the City's ADU FAQ lists Sacramento Area Sewer District (916-876-6100), Sacramento County Water Agency (916-874-6851), SMUD (916-732-5700), Golden State Water (1-800-999-4033), California American Water (916-568-4251) and Sacramento Metro Fire District (916-859-4330) as the agencies to contact. Quotes for the same scope commonly vary 20-40% between builders, so collect at least three bids.

Look for a licensed contractor with completed ADU projects in Rancho Cordova specifically — ADUs involve local zoning, setback rules, and utility connections that general remodelers may not have handled. Verify the license, ask for an ADU-specific portfolio and references, confirm they carry liability and workers' comp insurance, and get a written fixed-price or detailed bid. Submit a request below and we'll forward it to local ADU builders serving Rancho Cordova for free quotes.

Most full-service ADU builders manage the permit process for you. In Rancho Cordova the approval process is "Ministerial. "A permit application for an accessory dwelling unit shall be considered and approved ministerially without discretionary review or a hearing" (Gov. Code §66317(a)(1)) — no use permit, no variance, no Planning Commission. In practice it is a building permit: a completed building permit application with all submittal requirements, filed electronically with the Building Department through the City's online portal. Building and Safety takes application questions at (916) 851-8760 or PermitServices@cityofranchocordova.org; Planning is at (916) 851-8750 or PlanningServices@cityofranchocordova.org, 2729 Prospect Park Drive. A detached ADU can be assigned its own address on request during the building permit process provided it is physically detached, has separately billed and installed utilities and a mail receptacle; JADUs and attached ADUs cannot (contact Public Works at 916-851-8710). A local agency may not require correction of nonconforming zoning conditions as a condition of ministerial approval, nor deny an application because of unpermitted structures that do not threaten health and safety and are unaffected by the ADU (Gov. Code §66323(c) and §66322(b))" with a typical review timeline of The permitting agency must determine whether the application is complete and give written notice within 15 business days, and must approve or deny within 60 days of receiving a complete application where there is already a single-family or multifamily dwelling on the lot (Gov. Code §66317(a)(2)-(3)). If it misses the completeness deadline, the application is deemed complete. Where the ADU application is filed together with an application for a new primary dwelling, the agency may hold the ADU decision until it decides the primary. The City publishes an Estimated Project Review Timelines sheet for residential permits — ask Building and Safety at (916) 851-8760 for the current version. Confirm in writing whether permit fees, plan check (Building Division plan check as part of the building permit. Fire sprinklers are required in a newly built ADU only where the existing primary dwelling has an automatic residential sprinkler system; a dwelling built before sprinklers were required does not have to add one to take an attached ADU (City of Rancho Cordova ADU FAQ), which tracks Gov. Code §66314(d)(12) — an ADU may not be required to provide fire sprinklers if they are not required for the primary residence, and building an ADU may not trigger sprinklers in the existing house. The ADU structure may require photovoltaic panels under the California Energy Code. Construction of an ADU does not by itself constitute a Group R occupancy change under the local building code unless the building official makes a written finding on substantial evidence of a specific adverse impact on public health and safety (Gov. Code §66314(d)(8))), and impact fees are included in the bid or billed separately.

Plan for the permit review (The permitting agency must determine whether the application is complete and give written notice within 15 business days, and must approve or deny within 60 days of receiving a complete application where there is already a single-family or multifamily dwelling on the lot (Gov. Code §66317(a)(2)-(3)). If it misses the completeness deadline, the application is deemed complete. Where the ADU application is filed together with an application for a new primary dwelling, the agency may hold the ADU decision until it decides the primary. The City publishes an Estimated Project Review Timelines sheet for residential permits — ask Building and Safety at (916) 851-8760 for the current version in Rancho Cordova) plus construction. Most detached ADUs take 4-8 months of construction after permits are issued; garage conversions and prefab units are often faster. Ask each builder for a realistic schedule and what could delay it.