ADU permits are issued by the Rialto Building & Safety Division (150 S Palm Ave). State law (Gov. Code §66317) requires the city to act on a complete ADU application within 60 days, ministerially, with no discretionary hearing. Plans must comply with the California Building Standards Code (effective 2025 edition as of Jan. 1, 2026) and RMC Title 15.
Applications are submitted through Rialto's Online Permit Center (OPC). A typical ADU permit packet includes: site plan showing setbacks (min 4 ft side/rear per state preemption), floor plans, structural calcs, Title 24 energy compliance, and a fire-sprinkler determination (sprinklers cannot be required for an ADU unless required for the primary dwelling, per Gov. Code §66314(a)(1)(C)). The Building & Safety counter is open Mon-Fri 7 AM to 6 PM; inspector phone hours are 7-8 AM and 5-6 PM. After Dec. 31, 2025, all submittals must follow the 2025 California Building Standards. Plan check, building, electrical, plumbing, and mechanical permit fees apply per Rialto's adopted fee schedule (set under RMC Title 3 Revenue and Finance).
Starting construction before permit issuance triggers stop-work orders and investigation fees (typically 2x permit fee) under the California Building Code §110 as adopted by RMC Title 15. Failure to call for required inspections can result in tear-out and re-inspection charges.
Other ordinances people look up for this city. Green dot = verified primary-source excerpt.
Rialto, CA
Rialto requires permits for walls taller than 42 inches and building permits for all masonry and retaining walls. Block walls get three city inspections, and...
Rialto, CA
Barbed wire and razor wire are prohibited in all Rialto residential zones, and no sharp points may top any fence under six feet. City design standards also r...
Rialto, CA
Rialto caps household pets at four weaned dogs and cats combined, and no more than three of them may be dogs. The limit appears in Rialto Municipal Code Sect...
Rialto, CA
Backyard fires in Rialto are legal only as contained cooking or warming fires burning clean fuels such as propane, natural gas, charcoal, or untreated wood. ...
Rialto, CA
Removing a street or parkway tree requires prior written permission from the public services director, and the city's published criteria allow removal only o...
Rialto, CA
Rialto requires home-based businesses to obtain both a Home Occupation Permit from the Planning Division and a city business license. Under Rialto Municipal ...
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