Setback
A setback is the minimum required distance between a structure and the property line. Under California ADU law, detached ADUs need only a 4-foot side and rear setback — cities cannot require more — and a garage conversion staying inside the existing footprint generally needs no added setback.
The 4-foot state minimum is one of the biggest reasons ADUs fit on lots that couldn't accommodate a conventional addition. Front-yard setbacks still follow the underlying zoning. On a standard Sacramento interior lot, that 4-foot rule frees up the rear corner of the yard for a detached unit that a normal addition's larger setbacks would have pushed off the buildable area entirely. A Sacramento plan checker reviews the setback against objective standards only, so as long as the drawings show 4 feet to the side and rear lines, the unit cannot be denied on spacing — and a garage conversion that stays inside its existing walls clears the setback question altogether.
Go deeper:Sacramento ADU rules & setbacks
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