ADU Guide: Building an Accessory Dwelling Unit in Valencia

State law vs local rules

California Government Code 65852.2 (the state ADU law) sets a floor: every single family lot can have at least one ADU plus one Junior ADU. Cities can add layers on top but cannot block ADUs entirely. Valencia has its own ordinance that further shapes setbacks, height, and lot coverage.

Site feasibility

Before design, walk the lot for setbacks, sewer capacity, electrical service capacity, slope, and easement constraints. Detached new build ADUs need a footprint and yard space. Garage conversions reuse an existing structure. Junior ADUs sit inside the main house. Each path has its own cost basis and construction timeline.

Permits in {city}

ADU submittals are ministerial in California, meaning the city reviews them administratively without discretionary review. City of Santa Clarita Building and Safety. Online via santaclarita.gov. SCMC Title 17. typically completes plan check in 60 to 120 days. Master association CC&Rs include extensive design rules on color, material, roof form, and landscape. ADU plan check via city building department but HOA review required first. Garage conversions usually clear faster than detached new builds.

Construction window

Site clearance, foundation, framing, MEP rough, exterior dry in, interior finish, fixture install, final inspection. ADU builds in Valencia typically run 4 to 7 months of construction. From signed design contract to final inspection most projects total 8 to 14 months.