Pick the type, the size and the conditions on your lot. The estimate below is built from what ADUs actually cost in Los Angeles County in 2026, including drawings, engineering, energy-code paperwork, permits and construction. It is a planning range, not a quote.
This is a planning estimate, not a quote and not a bid. The rates behind it come from Los Angeles County projects and published 2026 cost data, reviewed 2026-10-29. Real pricing needs a site visit, because the things that move a construction budget most are rarely visible from the street. America General Contractors, California contractor licence CSLB 1083262.
Questions about this estimate
Is this a quote?
No. It is a planning range built from what ADUs actually cost across Los Angeles County in 2026. A real price needs a site visit, because the things that move an ADU budget most, sewer capacity, panel capacity, access and slope, are only knowable on the lot.
Does it include permits and drawings?
Yes. Drawings, structural engineering, the energy-code report, city permit and plan check fees and school fees are all in the breakdown. Most online ADU numbers are construction only, which is why real projects feel more expensive than what people read.
Why is the range so wide?
Because site conditions genuinely swing an ADU budget by six figures. A flat lot with the sewer ten feet away and a panel with spare capacity is a different project from a sloped lot needing a new main line and a service upgrade.
What does an ADU rent for in Los Angeles?
A one-bedroom in a central or westside neighborhood commonly rents in the low-to-mid $2,000s or above. We will model the return against the build cost with you before you spend anything on drawings.
Read more
For the full picture, see adu & garage conversion and the the los angeles adu guide.
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