#1 ADU Contractor in San Fernando
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Finding the right adu contractor in San Fernando means understanding both the state rules that shape what is allowed and the physical realities of the lots where the work actually happens. California consolidated its ADU statutes into Government Code sections 66310 through 66342 in 2024, and those rules changed again on January 1, 2026. Square footage is now measured as interior livable space, and once an application lands with the reviewing agency, that agency has 15 business days to determine whether the submission is complete and 60 days to approve or deny it. Approval is ministerial, meaning no public hearing and no discretionary design review.

In San Fernando, that application goes to the City of San Fernando Building and Safety Division. No unusual local overlay applies here, so the building code and the condition and age of the house are what govern the project. That is a straightforward starting point compared to some jurisdictions, but it is still worth noting how much the counter changes across the region. Los Angeles County has 88 incorporated cities, and the agency, the forms, and the review timeline shift from one city to the next even when the underlying state statute does not.

The county’s own ADU ordinance, which covers unincorporated territory rather than incorporated cities like San Fernando, was amended in July 2025 and then found non-compliant with state law by the California Department of Housing and Community Development in December 2025. Among the findings, the ordinance caps detached ADUs on multifamily lots at two where state law permits up to eight. San Fernando is not governed by that ordinance, but the situation is a useful reminder that a local handout or summary sheet is not always current with the statute.

State law also sets a floor on what a local agency can require or restrict. A city cannot cap an ADU below 850 square feet of interior livable space, or below 1,000 square feet for a unit with more than one bedroom. Side and rear setbacks cannot exceed four feet. Owner-occupancy cannot be required as a condition of building an ADU. Adding a unit cannot trigger a fire sprinkler retrofit of the main house. And there are no impact fees on a unit of 750 square feet or less.

San Fernando’s housing stock grew in across the twentieth century on a dense grid that traces back to the townsite incorporated in August 1911. Most parcels hold a small single-family or two-family dwelling, and lot width is often the first constraint we run into. A narrow lot shapes where a detached unit can sit, how far utilities have to run from the main structure, and whether a garage conversion or a new detached build is the more practical answer. We walk the parcel and check setbacks, grade, equipment access, and utility routes before drawing anything, because the lot decides most of what follows.